text stringlengths 454 608k | url stringlengths 17 896 | dump stringclasses 91
values | source stringclasses 1
value | word_count int64 101 114k | flesch_reading_ease float64 50 104 |
|---|---|---|---|---|---|
I think this one is pretty clever... I use PS3MediaServer to stream to my PS3, and have it sort by date, such that new stuff is always on top... however is things are downloaded after PS3MS starts, they end up being appended (to the bottom). This is pretty wonky, so my solution is, whenever a file finishes downloading, restart the PS3MS service, but only if the PS3 isn't connected. I also have this run as an hourly cronjob, so if the PS3 is connected when a download finishes, the "re-ordering" doesn't wait until the next download to happen.
Code: Select all
#!/usr/bin/python
import os
import subprocess
import sys
p1 = subprocess.Popen(["netstat", "-tunv"], stdout=subprocess.PIPE)
p2 = subprocess.Popen(["grep", ":5001"], stdin=p1.stdout, stdout=subprocess.PIPE)
if os.waitpid(p2.pid, 0)[1]:
# print "restarting PS3M"
pstop = subprocess.Popen(["/etc/init.d/PS3MediaServer", "stop"], stdout=subprocess.PIPE)
os.waitpid(pstop.pid,0)
pstart = subprocess.Popen(["/etc/init.d/PS3MediaServer", "start"], stdout=subprocess.PIPE)
os.waitpid(pstart.pid,0)
# print "PS3M restarted"
#else:
# print "connections found"
The following is a simple script to send a prowl alert whenever a torrent completes.
Code: Select all
#!/bin/bash
curl -k -F apikey=X -F application="Deluge" -F event="Torrent Completed" -F description="$2" &
The next two scripts work together...
The first one is run on torrent completion, and if a torrent is being downloaded to "/*/*/Files/", it makes a symlink to it in "/media/2TB/New Files"
The second runs on a daily cronjob, and removes any links in "/media/2TB/New Files/" that are over 6 days old.
The net effect, clearly, is that "/media/2TB/New Files/" contains symlinks to all of the new downloads (less than 6 days old)
Code: Select all
#!/usr/bin/python
import sys
import os
if sys.argv[3].split('/')[3] == 'Files':
os.system("ln -s \""+sys.argv[3]+sys.argv[2]+"\" /media/2TB/New\ Files/")
Code: Select all
#!/bin/bash
find /media/2TB/New\ Files/ -mtime +6 -type l -exec rm {} \;
find -L /media/2TB/New\ Files/ -type l -delete | http://forum.deluge-torrent.org/viewtopic.php?f=9&t=35057&sid=5605bbe43f089640747ed8cfde264d1f | CC-MAIN-2018-09 | refinedweb | 351 | 60.11 |
Request Headers
A typical HTTP message in a SOAP request being passed to a Web server looks like this:
POST /Order HTTP/1.1 Host: Content-Type: text/xml Content-Length: nnnn SOAPAction: "urn:northwindtraders.com:PO#UpdatePO" Information being sent would be located here.
The first line of the message contains three separate components: the request method, the request URI, and the protocol version. In this case, the request method is POST; the request URI is /Order; and the version number is HTTP/1.1. The Internet Engineering Task Force (IETF) has standardized the request methods. The GET method is commonly used to retrieve information on the Web. The POST method is used to pass information from the client to the server. The information passed by the POST method is then used by applications on the server. Only certain types of information can be sent using GET; any type of data can be sent using POST. SOAP also supports sending messages using M-POST. We'll discuss this method in detail later in this chapter. When working with the POST method in a SOAP package, the request URI actually contains the name of the method to be invoked.
The second line is the URL of the server that the request is being sent to. The request URL is implementation specific-that is, each server defines how it will interpret the request URL. In the case of a SOAP package, the request URL usually represents the name of the object that contains the method being called.
The third line contains the content type, text/xml, which indicates that the payload is XML in plain text format. The payload refers to the essential data being carried to the destination. The payload information could be used by a server or a firewall to validate the incoming message. A SOAP request must use the text/xml as its content type. The fourth line specifies the size of the payload in bytes. The content type and content length are required with a payload.
The SOAPAction header field must be used in a SOAP request to specify the intent of the SOAP HTTP request. The fifth line of the message, SOAPAction: "urn: northwindtraders.com:PO#UpdatePO", is a namespace followed by the method name. By combining this namespace with the request URL, our example calls the UpdatePO method of the Order object and is scoped by the urn:northwindtraders.com:PO namespace URI. The following are also valid SOAPAction header field values:
SOAPAction: "UpdatePO" SOAPAction: "" SOAPAction:
The header field value of the empty string means that the HTTP request URI provides the intent of the SOAP message. A header field without a specified value indicates that the intent of the SOAP message isn't available.
Notice that there is a single blank line between the fifth line and the payload request. When you are working with message headers, the carriage-return/line-feed sequence delimits the headers and an extra carriage-return/line-feed sequence is used to signify that the header information is complete and that what follows is the payload.
Response Headers
A typical response message that contains the response headers is shown here:
200 OK Content-Type: text/plain Content-Length: nnnn Content goes here.
The first line of this message contains a status code and a message associated with that status code. In this case, the status code is 200 and the message is OK, meaning that the request was successfully decoded and that an appropriate response was returned. If an error had occurred, the following headers might have been returned:
400 Bad Request Content-Type: text/plain Content-Length: 0
In this case, the status code is 400 and the message is Bad Request, meaning that the request cannot be decoded by the server because of incorrect syntax. You can find other standard status codes in RFC 2616. | https://www.brainbell.com/tutors/XML/XML_Book_B/Request_Headers.htm | CC-MAIN-2019-04 | refinedweb | 648 | 62.68 |
I want to detect polynomials of the form
x^n + m in a python script.
Found this helpful piece of code that works perfectly in sage's jupyter notebook:
x = var('x') w0 = SR.wild(0) w1 = SR.wild(1) (x**2-2).find(x**w0+w1)
However, when I throw this into a
.py file and run it I get the error
*** TypeError: unsupported operand parent(s) for ^: 'Symbolic Ring' and 'Symbolic Ring'
Minimal Failing Example:
from sage.all import * import sage from sage.calculus.var import var from sage.symbolic.ring import SymbolicRing SR = SymbolicRing() polynomial = SR('x^2-2') x = var('x') w0 = SR.wild(0) w1 = SR.wild(1) polynomial.find(x**w0+w1)
What am I missing? | https://ask.sagemath.org/questions/59497/revisions/ | CC-MAIN-2022-21 | refinedweb | 122 | 62.24 |
Hi guys,
I have bundled the ExtJS theme "2brave" (created by wregen, details here:) for ExtGWT. This easy-to-use JAR file can be used the same way as "Slate" theme described here:.
I tested this JAR with GWT 1.5.2 and Ext-GWT 1.0.4.
Usage:
Insert this to your *.gwt.xml file:
Then add the JAR file to your classpath.Then add the JAR file to your classpath.Code:
<inherits name='ext.ux.theme.brave.Brave'/>
Then add this to your ExtGWT Java code:
And then register the theme as follows:And then register the theme as follows:Code:
import ext.ux.theme.brave.client.Brave;
Enjoy!Enjoy!Code:
ThemeManager.register(Brave.BRAVE);
Cypher
PS:
The attached file gxt-theme-brave-1.0.zip needs to be renamed to gxt-theme-brave-1.0.jar and then included in your ExtGWT project. | https://www.sencha.com/forum/printthread.php?t=47046&pp=10&page=1 | CC-MAIN-2017-04 | refinedweb | 146 | 62.24 |
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Basic C# Programming: Test Your Knowledge
Test your knowledge of the absolute basics of C#. If you started learning C# recently but you're still getting the syntax straight in your head, these exercises are for you.If you get stuck anywhere, ....
C# for Beginners: Make Your Own MP3 Player, Free
C# is so ridiculously simple that even a beginner can make an MP3 player in no time at all using the free Express edition of Visual C#. I've used the 2010 edition for this tutorial, but other versions....
Free GUID Generator for Windows
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C# Protected: Using the Protected Keyword in C#
In C#, you can specify that instance variables and methods are public , protected , internal or private .If the internal keyword is unfamiliar to you, you might want to check out my article on ....
C# Array: Using Arrays in C#
Arrays in C# are easy to use, unlike their pricklier C++ relatives.In this article we'll take a look at some code examples that demonstrate how arrays are used. But before you jump in there with that ....
C# Methods
Methods are simply subroutines that are attached to some object. For instance, a 'car' object might have a method called 'start' that starts the car (of course we could be speaking here either about....
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Classes in C# are created using the keyword class . Usually you also declare classes in a namespace , but this is not obligatory. In fact to declare a class, all you need at the minimum is the clas....
C# Hello World
C# is undoubtedly one of the easiest languages to get started in. In this brief tutorial we'll create a Hello World console application using Microsoft's free Visual C# express. ....
C# Float -- Usage, Minimum and Maximum Values
You can represent floating point values in C# using either the float or decimal types. While decimal is more suited to financial calculations due to its smaller range but greater precision, you ....
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All pages and content copyright © 2014-2017 John Purcell, except where specifically credited to other authors. | https://caveofprogramming.com/categories/c-sharp-tutorial/index.html | CC-MAIN-2018-09 | refinedweb | 428 | 62.88 |
Domain Driven Design with Web API revisited Part 18: tests and conclusions
October 5, 2015 2 Comments
Introduction
In the previous post we continued working on our Web API 2 layer and added two new controller actions: POST which handles both updates and insertions and DELETE which is responsible for deleting load tests. Our first draft of the DDD load testing demo is actually finished at this point. All that’s left is testing the POST and DELETE functions of the Web API.
We’ll do that in this post. We’ll also write some conclusions.
Testing
There are various tools out there that can generate any type of HTTP calls for you where you can specify the JSON inputs, HTTP headers etc. However, we’re programmers, right? We don’t need any extra tools, we can write a simple one ourselves! Don’t worry, I only mean a GUI-less throw-away application that consists of a few lines of code, not a complete Fiddler.
Fire up Visual Studio and create a new Console application. I called mine PostDeleteActionTester but it doesn’t matter, it’s not part of the main DDD demo solution.
We’ll be sending the InsertUpdateLoadtestViewModel objects to the Web API 2 in JSON format. We’ll need a JSON library for that and we’ll go for the #1 JSON.NET library out there. Add the following NuGet package to the console app:
We’ll need to serialise InsertUpdateLoadtestViewModel objects from the console application. The easiest way to do that is to insert that same class into the console app as well but without the conversion function, we won’t need that. Add the following 2 objects to the console tester app:
public class InsertUpdateLoad StartDate StartDate { get; set; } public int UserCount { get; set; } public int DurationSec { get; set; } }
public class StartDate { public int Year { get; set; } public int Month { get; set; } public int Day { get; set; } public int Hour { get; set; } public int Minute { get; set; } public string Timezone { get; set; } }
We’ll get the valid time zone strings using the list available on this Microsoft documentation page.
Next add a reference to the System.Net.Http library version 4.0.0.0. We’ll need it in order to send HTTP requests to the DDD web.
We’ll also need to take note of the exact URL of the local load testing demo project. Open the WebSuiteDDD.Demo solution and start the project. Take note of the exact localhost URL, such as “”. Then insert the following private variable to Program.cs in the console tester app:
private static Uri _serviceUri = new Uri("");
Testing the POST action method
The following method will test the Post action method of the Web API:
private static void RunPostOperation() { HttpRequestMessage requestMessage = new HttpRequestMessage(HttpMethod.Post, _serviceUri); requestMessage.Headers.ExpectContinue = false; List<InsertUpdateLoadtestViewModel> vms = new List<InsertUpdateLoadtestViewModel>(); InsertUpdateLoadtestViewModel first = new InsertUpdateLoadtestViewModel() { AgentCity = "Seattle", AgentCountry = "USA", CustomerName = "OK Customer", DurationSec = 600, EngineerName = "Jane", LoadtestTypeShortDescription = "Stress test", ProjectName = "Third project", ScenarioUriOne = "", StartDate = new StartDate() { Year = 2015, Month = 8, Day = 22, Hour = 15, Minute = 30, Timezone = "E. Europe Standard Time" }, UserCount = 30 }; InsertUpdateLoadtestViewModel second = new InsertUpdateLoadtestViewModel() { AgentCity = "Frankfurt", AgentCountry = "Germany", CustomerName = "Great customer", DurationSec = 20, EngineerName = "Fred", LoadtestTypeShortDescription = "Capacity test", ProjectName = "First project", ScenarioUriOne = "", ScenarioUriTwo = "", StartDate = new StartDate() { Year = 2015, Month = 8, Day = 21, Hour = 16, Minute = 00, Timezone = "Nepal Standard Time" }, UserCount = 50 }; vms.Add(first); vms.Add(second); string jsonInput = JsonConvert.SerializeObject(vms); requestMessage.Content = new StringContent(jsonInput, Encoding.UTF8, "application/json");(); }
You’ll see that we attempt to add 2 load tests. You’ll also notice how we serialise the view models using Json.NET and add it to the payload of the request. We deliberately specify a long timeout of 10 minutes so that you can step through the code in the demo project without generating a timeout exception in the tester application. Feel free to adjust the properties of the test values above the way you like.
You can now start the DDD demo first. Then call RunPostOperation() from the Main function and run the tester application. It can be a good idea to set a breakpoint within the Post method of LoadtestsController so that you can go through the code step by step and see how the different projects and classes are connected.
Depending on what you send as test values you’ll get different responses. Here’s a successful insertion:
Here’s an example showing a double-booking:
Here comes a validation error with a too short test duration:
Finally here’s an exception message about a wrong start date:
Testing the DELETE action method
Testing the Delete action method is even easier. The following method in Program.cs will be enough:
private static void RunDeleteOperation() { HttpRequestMessage requestMessage = new HttpRequestMessage(HttpMethod.Delete, string.Concat(_serviceUri, "/e3d4012c-50f6-4a58-af3a-5debfc40a01d")); requestMessage.Headers.ExpectContinue = false;(); }
As you can see we simply attach the ID to the end of the loadtests URL. You can then call this method from Main, add a breakpoint to the Delete method of LoadtestsController and test the deletion chain. If you attach a valid load test ID to the URL then you should simply get a message saying “Deleted”. Otherwise you’ll be given an exception message:
Conclusions
That actually completes the revised DDD project. Most of the conclusions from the original DDD project are still valid. Most importantly we still have a solution with an independent domain layer. Also, the technology-driven EF layer is not referenced directly by any other layer in the solution.
If we start from the top then we see that the web layer talks to the service layer through the ITimetableService interface. The ITimetableService interface uses RequestResponse objects to communicate with the outside world. Any implementation of ITimetableService will communicate through those objects so their use within LoadtestsController is acceptable as well.
The application service layer has a reference to the SharedKernel layer – through the DDD-related abstractions – and the Domain layer. In a full-blown project there will be more links to the SharedKernel and possibly a separate common Infrastructure layer – logging, caching, authentication etc. – but as longs as you hide those concerns behind abstractions you’ll be fine. The Loadtest repository is only propagated in the form of interfaces – ITimetableRepository and ITimetableViewModelRepository. Otherwise the domain objects are allowed to bubble up to the Service layer as they are the central elements of the application.
The Domain layer has a dependency on the SharedKernel layer through abstractions such as EntityBase and IAggregateRoot. That’s all fine and good.
The repository layer has a reference to the SharedKernel layer – again through abstractions such as IAggregateRoot – and the Domain layer. Notice that the domain layer does not depend on the repository but the repository depends on the domain layer.
I think the most significant property of the demo abstractions. You can then instruct StructureMap to use a different data store. I’m planning to extend this basic project with a different data store namely MongoDb.
The domain layer is still the central one in the solution. The services, Web API and data access layers directly reference it.
That’s all folks for now. It’s been a long journey of 18 posts and we’re still only scratching the surface of DDD. I hope you have learned new things and can use this solution in some way in your own project. I’m planning to get out a couple of extensions to this demo which I’ll provide the link to as they become available.
Here’s the first extensions: messaging.
View the list of posts on Architecture and Patterns here.
Thank you for this series. It’s been very helpful trying get a firmer understanding of domain driven design and how it plays together with a real system like WebAPI.
Is there a download somewhere for the complete Visual Studio solution? Seeing it all together in one place and how the dependencies work would be very helpful.
Thanks!
Hi Nick,
Thanks for your comment. You can always check out the Github page available from the top menu. Here’s the repository for the updated DDD project:
//Andras | https://dotnetcodr.com/2015/10/05/domain-driven-design-with-web-api-revisited-part-18-tests-and-conclusions/ | CC-MAIN-2021-17 | refinedweb | 1,362 | 55.34 |
Question?
Answer to relevant QuestionsCongratulations! You have just won a $40 million lottery and have elected to receive $2 million per year for 20 years. Assume that a 4 percent interest rate is used to evaluate the annuity and that you receive each payment ...Regarding question 7b, if Sam believes he will earn 10 percent on his investment for retirement, how much does he have to contribute to his retirement account at the beginning of each year to accumulate his retirement nest ...How does the accounting rate of return (ARR) differ from the internal rate of return (IRR)? What is the payback if investment cost is $45,000 and the after tax benefit is $2,000? If the 10 percent present value ordinary annuity factor (PVAF) is 8.5136 and the 11 percent PVAF is 7.9633, a PVAF of 8.1234 correlates to an internal rate of return of _______.
Post your question | http://www.solutioninn.com/the-city-of-glendale-borrows-48-million-by-issuing-municipal | CC-MAIN-2017-09 | refinedweb | 154 | 66.23 |
strchr() prototype
const char* strchr( const char* str, int ch ); char* strchr( char* str, int ch );
The
strchr() function takes two arguments: str and ch. It searches for the character ch in the string pointed to by str.
It is defined in <cstring> header file.
strchr() Parameters
ptr: Pointer to the null terminated string to be searched for.
ch: Character to search for.
strchr() Return value
If the character is found, the
strchr() function returns a pointer to the location of the character in str, otherwise returns null pointer.
Example: How strchr() function works
#include <cstring> #include <iostream> using namespace std; int main() { char str[] = "Programming is easy."; char ch = 'r'; if (strchr(str, ch)) cout << ch << " is present \"" << str << "\""; else cout << ch << " is not present \"" << str << "\""; return 0; }
When you run the program, the output will be:
r is present "Programming is easy." | https://www.programiz.com/cpp-programming/library-function/cstring/strchr | CC-MAIN-2020-16 | refinedweb | 144 | 70.23 |
getrusage()
Get information about resource utilization
Synopsis:
#include <sys/resource.h> int getrusage( int who, struct rusage * r_usage );
Arguments:
- who
- Which process to get the usage for:
- RUSAGE_CHILDREN — get information about resources used by the terminated and waited-for children of the current process. If the child is never waited for (e.g if the parent has SA_NOCLDWAIT set, or sets SIGCHLD to SIG_IGN), the resource information for the child process is discarded and isn't included.
- RUSAGE_SELF — get information about resources used by the current process.
- r_usage
- A pointer to an object of type struct rusage in which the function can store the resource information; see below.
Library:
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
Description:
The getrusage() function provides measures of the resources used by the current process or its terminated and waited-for child processes, depending on the value of the who argument.
The rusage structure is defined as: " */ " */
The members include:
- ru_utime
- The total amount of time, in seconds and microseconds, spent executing in user mode.
- ru_stime
- The total amount of time, in seconds and microseconds, spent executing in system mode.
- ru_maxrss
- The maximum resident set size, given in pages. See the Caveats section, below.
- ru_ixrss
- Not currently supported.
- doesn't take sharing into account. See the Caveats section, below.
- ru_isrss
- Not currently supported.
- ru_minflt
- The number of page faults serviced that didn't require any physical I/O activity. See the Caveats section, below.
- ru_majflt
- The number of page faults serviced that required physical I/O activity. This could include page ahead operations by the kernel. See the Caveats section, below
- ru_nswap
- The number of times a process was swapped out of main memory.
- ru_inblock
- The number of times the file system had to perform input in servicing a read() request.
- ru_oublock
- The number of times the filesystem had to perform output in servicing a write() request.
- ru_msgsnd
- The number of messages sent over sockets.
- ru_msgrcv
- The number of messages received from sockets.
- ru_nsignals
- The number of signals delivered.
- ru_nvcsw
- The number of times a context switch resulted due to a process's voluntarily giving up the processor before its timeslice was completed (usually to await availability of a resource).
- ru_nivcsw
- The number of times a context switch resulted due to a higher priority process's becoming runnable or because the current process exceeded its time slice.
Returns:
Errors:
- EFAULT
- The address specified by the r_usage argument isn't in a valid portion of the process's address space.
- EINVAL
- Invalid who parameter.
Classification:
Caveats:
Only the timeval fields of struct rusage are supported. reference by the program to a page that isn't in memory. Now, however, the kernel can generate page faults on behalf of the user, for example, servicing read() and write() don, a minor page fault results for the address space. Also, anyone doing a read() or write() to something that's in the page cache gets a minor page fault(s) as well.
There's no way to obtain information about a child process that hasn't yet terminated. | https://developer.blackberry.com/playbook/native/reference/com.qnx.doc.neutrino.lib_ref/topic/g/getrusage.html | CC-MAIN-2020-10 | refinedweb | 521 | 57.37 |
#include <iostream> #include <string> #include <algorithm> #include <vector> #include <list> #include <stdio.h> #include <stdint.h> using namespace std; int main() { list<string> rucksack; string input; cout << "which items would you like to put in your rucksack"; getline(cin, input); vector<string> keywords{"bow", "sword", "scales", "cloak"}; for(const auto& keyword : keywords) { auto pos = input.find(keyword); cout << ..
Category : cl am having some issues with the LLDB debugger. If I create an array of std::vector with a literal (e.g. vector<int> a[3];), I can freely view it in the debugger variables. However, if I specify the length with a variable (e.g. int n = 3; vector<int> a[n];), the debugger displays "parent failed to evaluate: variable ..
I have a C++ project described by a CMakeLists.txt file from which CMake successfully generates a MAKE file if I call CMake from the terminal. (This is on Ubuntu.) The project has dependencies on Boost and Eigen which are both installed on my system. I can see the Boost includes in /usr/include/boost, Boost binaries in ..
I have created a new C++11 project on Clion and ran it locally which gave me no errors at all. But, when I ran it on an external server like this: g++ -std=c++11 -DNDEBUG -Wall *.cpp I got few error (which I was able to correct them later). My question is how can I prevent ..
I am trying to include boost library to clion using the following CMakeLists.txt cmake_minimum_required(VERSION 3.16) project(Prototype3Relational) set(CMAKE_CXX_STANDARD 20) set(Boost_INCLUDE_DIR "F:Essentialboost_1_74_0") find_package(Boost) include_directories(${Boost_INCLUDE_DIR}) add_executable(Prototype3Relational main.cpp atomic_logic.h logic_engine.h F.h) but it seems to take forever to index. Most of which are irrelevant like the docs,examples, a few HTML files here and there and a lot . It ..
I am trying to use windows boost 1.74.0 library in clion and all i get is errors. Maybe i am missing something in my CMakeLists.txt which looks as follows. cmake_minimum_required(VERSION 3.16) project(Prototype3Relational) set(CMAKE_CXX_STANDARD 20) set(Boost_INCLUDE_DIR "F:Essentialboost_1_74_0") find_package(Boost COMPONENTS lambda REQUIRED) include_directories(${Boost_INCLUDE_DIR}) add_executable(Prototype3Relational main.cpp atomic_logic.h logic_engine.h F.h) Every time i reload cmakeproject i get an error .. ..
So, I have no code, just empty files and a CMake, but I keep getting that Linker Error. Can someone please explain in a lot of detail what my problem is? Some info I have is that I am supposed to be using Visual Studio 2015 as my compiler and stuff, which I think I ..
please tell me what the problem may be, I wrote a program in C++ under Linux, but there was a problem with the execl () function, it gives the following error "No such file or directory", please tell me what I’m doing wrong? The code of the main program(the main file) where excel is called(the ..
Recent Comments | https://windowsquestions.com/category/clion/ | CC-MAIN-2020-50 | refinedweb | 490 | 58.08 |
I am trying to write a function that uses a while loop. The program must find the average, maximum and minimum of the numbers that the user inputs. Then I need to call the function from another module. I have managed to get the average to work, but I cannot use the max() and min() functions correctly it seems.
The error message I get is:
Traceback (most recent call last):
File "C:\Users\Scott\workspace\woooo\herro.py", line 6, in <module>
total, average, smallest = maggiespizza.sla(n)
File "C:\Users\Scott\workspace\woooo\maggiespizza.py", line 15, in sla
smallest = min (x)
TypeError: 'int' object is not iterable
Here is my code:
- Code: Select all
def sla (n):
FIRST_N = n
total = 0
while n > 0:
x = int(input("Enter a value: "))
total += x
n = n - 1
average = total / FIRST_N
smallest = min (x)
return total, average, smallest | http://python-forum.org/viewtopic.php?p=5056 | CC-MAIN-2016-36 | refinedweb | 147 | 63.29 |
Hello, +1 (non-binding)
Advertising
I was able to successfully build and deploy the war files for Stanbol 1.0.0. Some simple testing shows everything working properly. I was also able to run the genericrdf indexer over a custom vocabulary (80 million triples) with success. I look forward with working more with this release! Thanks everyone. Aaron Coburn > On Sep 21, 2016, at 3:45 PM, A. Soroka <aj...@virginia.edu> wrote: > > Thank you for moving the release process forward! > > > > --- > A. Soroka > The University of Virginia Library > >> On Sep 21, 2016, at 3:27 PM, Rafa Haro <rh...@apache.org> wrote: >> >> Thanks a lot Soroka! >> El El mié, 21 sept 2016 a las 21:00, A. Soroka <aj...@virginia.edu> >> escribió: >> >>> I was able to build the same release code on OS X 10.10.5 using Java >>> 1.8.0_40 via mvn clean install. As a simple test, I was able to use the >>> EntityHub Generic indexer to index a medium-sized vocabulary of interest to >>> my site without difficulty. I did notice that the default config for the >>> Generic indexer uses the namespace prefix bio: for >>>, which is apparently no longer an included >>> preset. This throws a warning during operation [1}. Also, the usage note >>> for the Generic indexer refers to >>> "org.apache.stanbol.indexing.core-*-jar-with-dependencies.jar" when in fact >>> the artifact is now called >>> "org.apache.stanbol.entityhub.indexing.genericrdf-*.jar". I can send a PR >>> for these minor annoyances if that would be useful. >>> >>> >>> --- >>> A. Soroka >>> The University of Virginia Library >>> >>> [1] E.g. >>> >>> 14:40:46,767 [main] WARN mapping.FieldMappingUtils - Unable to parse >>> fieldMapping because of unknown namespace prefix >>> java.lang.IllegalArgumentException: The prefix 'bio' is unknown (not >>> mapped to an namespace) by the Stanbol Namespace Prefix Mapping Service. >>> Please change the configuration to use the full URI instead of 'bio:*'! >>> >>> >>> >>>> On Sep 20, 2016, at 2:07 PM, steve reinders <steve...@gmail.com> wrote: >>>> >>>> All, >>>> >>>> - I downloaded from >>> >>>> to OSX 10.11.6 ( 9:00 PM US CST Mon Sep 19 ) >>>> - using 1.8.0_25 ( oracle ) >>>> - built w/mvn install >>>> - only problem was CELI license >>>> - produced org.apache.stanbol.launchers.full-1.0.0.jar >>>> >>>> TopicClassifier looks to have been built fine. >>>> >>>> Is this the source's correct source ? >>>> >>>> BTW is the CMS REST interface in ? Can't tell easily in Jira and I knew >>> it >>>> was pulled in earlier version. >>>> >>>> danke >>>> >>>> Steve >>>> >>>> >>>> On Tue, Sep 20, 2016 at 12:00 PM, Rafa Haro <rh...@apache.org> wrote: >>>> >>>>> Hi Cristian, >>>>> >>>>> Apparently the Topic Annotation engine is only compiling with OpenJDK >>>>> 1.8.x. As far as I know, that code has remained untouched since long >>> time >>>>> ago, but we should probably remove that dependency (although I don't >>> see it >>>>> a problem for not going ahead with the release). >>>>> >>>>> By the way, I have checked the artifacts and signatures, built also from >>>>> source without problems >>>>> >>>>> Therefore +1 for me >>>>> >>>>> Cheers, >>>>> Rafa >>>>> >>>>> On Mon, Sep 19, 2016 at 10:37 PM Rafa Haro <rh...@apache.org> wrote: >>>>> >>>>>> Hi Cristian, >>>>>> >>>>>> I build it directly from the SVN tag and didn't have any problem. I >>> will >>>>>> check tomorrow the source packages >>>>>> >>>>>> Thanks, >>>>>> Rafa >>>>>> El El lun, 19 sept 2016 a las 22:21, Cristian Petroaca < >>>>>> cristian.petro...@gmail.com> escribió: >>>>>> >>>>>>> Hi guys, >>>>>>> >>>>>>> I downloaded the sources from here >>>>>>> dist/dev/stanbol/1.0.0/ >>>>>>> <> and did a >>> "mvn >>>>>>> install" but some tests failed with: >>>>>>> Tests run: 7, Failures: 0, Errors: 5, Skipped: 0, Time elapsed: 4.33 >>> sec >>>>>>> <<< FAILURE! - in org.apache.stanbol.enhancer. >>>>> engine.topic.TopicEngineTest >>>>>>> >>>>>>> testCrossValidation(org.apache.stanbol.enhancer. >>>>> engine.topic.TopicEngineTest) >>>>>>> Time elapsed: 2.108 sec <<< ERROR! >>>>>>> java.lang.NoClassDefFoundError: Could not initialize class >>>>>>> sun.security.provider.SecureRandom$SeederHolder >>>>>>> at >>>>>>> sun.security.provider.SecureRandom.engineNextBytes( >>>>> SecureRandom.java:221) >>>>>>> at java.security.SecureRandom.nextBytes(SecureRandom.java:468) >>>>>>> at java.util.UUID.randomUUID(UUID.java:145) >>>>>>> at >>>>>>> >>>>>>> org.apache.stanbol.enhancer.engine.topic.TopicClassificationEngine. >>>>> addConcept(TopicClassificationEngine.java:790) >>>>>>> at >>>>>>> >>>>>>> org.apache.stanbol.enhancer.engine.topic.TopicClassificationEngine. >>>>> addConcept(TopicClassificationEngine.java:825) >>>>>>> at >>>>>>> >>>>>>> org.apache.stanbol.enhancer.engine.topic.TopicEngineTest. >>>>> initArtificialTrainingSet(TopicEngineTest.java:537) >>>>>>> at >>>>>>> >>>>>>> org.apache.stanbol.enhancer.engine.topic.TopicEngineTest. >>>>> testCrossValidation(TopicEngineTest.java:475) >>>>>>> >>>>>>> Java version: >>>>>>> java version "1.8.0_77" >>>>>>> Java(TM) SE Runtime Environment (build 1.8.0_77-b03) >>>>>>> Java HotSpot(TM) 64-Bit Server VM (build 25.77-b03, mixed mode) >>>>>>> >>>>>>> >>>>>>> My java version is the Oracle one, not OpenJDK. >>>>>>> I looked that class up, SecureRandom, but I can't find it in Oracle's >>>>>>> documentation in that package but rather here: >>>>>>> >>>>> security/SecureRandom.html >>>>>>> >>>>>>> Not sure if this is the problem. >>>>>>> >>>>>>> Cristian >>>>>>> >>>>>>> On Sat, Sep 17, 2016 at 1:55 PM, Antonio David Pérez Morales < >>>>>>> adperezmora...@gmail.com> wrote: >>>>>>> >>>>>>>> Tested >>>>>>>> >>>>>>>> +1 for me >>>>>>>> >>>>>>>> Regards >>>>>>>> >>>>>>>> El 16 sept. 2016 6:38 p. m., "Rafa Haro" <rh...@apache.org> >>> escribió: >>>>>>>> >>>>>>>>> Hi devs, >>>>>>>>> >>>>>>>>> Please vote on wether to release Apache Stanbol 1.0.0 RC0. This is >>>>> the >>>>>>>>> first 1.x.x release and the first release since version 0.12 (more >>>>>>> than 2 >>>>>>>>> years ago). Therefore, it is not easy to summarize all the changes >>>>>>> since >>>>>>>>> then. Please refer to >>>>>>> for >>>>>>>> an >>>>>>>>> exhaustive list of issues fixed in this version. >>>>>>>>> >>>>>>>>> The release source code can be found at the following tag: >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> The release includes the complete Apache Stanbol stack with all >>>>>>>> components. >>>>>>>>> The release artifacts are staged at: >>>>>>>>> >>>>>>>>> >>>>>>>> orgapachestanbol-1009/ >>>>>>>>> >>>>>>>>> and the source packages here: >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> You can check the staged Maven artifacts using the script in >>>>>>> 'releasing' >>>>>>>>> ./check_staged_release.sh 1009 [tmp-directory] >>>>>>>>> >>>>>>>>> PGP release singing keys are available at: >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> The vote will be open for 72 hours >>>>>>>>> >>>>>>>> >>>>>>> >>>>>> >>>>> >>> >>> > | https://www.mail-archive.com/dev@stanbol.apache.org/msg04581.html | CC-MAIN-2016-40 | refinedweb | 930 | 51.95 |
Grab 5 page flags for some upcoming VM projects and convert the Compoundpage flag handling to use 2 bits (necessary so that page cache flag usedoes no longer overlap with compound flags).This makes us use 24 page flags (plus one additional flag for 64bit)On a 64 bit system 32 bits are used for page flags. Of those we use25 flags. So 7 flags are still available.The rest applies only to 32 bit systems:In non NUMA configurations we need 2 bits for the zoneid. Meaning30 bits are left. Of those 24 are used for page flags. So 6 flagsare still available.In NUMA configuration these 6 bits could be used for node numberswhich would result in the ability to support 64 nodes.However, the highest number of suported nodes on 32 bit is NUMAQ with16 nodes. This means we need to use only 4 bits. So 2 page flagsare still available.32bit Sparsemem without vmemmap:The page flags situation becomes very tight. The remaining 6 bits must thenbe used as section ids. Via a lookup table we can determine the node ids fromthe section id. So it would work.However, we would have no page flags left. Any additional page flag willreduce the number of available sparsemem sections to half.It may be good if we could phase out sparsemem w/o vmemmap for 32 bitsystems. It is likely that most of memory is backed by contiguous RAM givencurrently available memory sizes.Without the 32bit sparsemem issues we would still have 2 page flags available.Which would be the same situation as before this patchset and the page flagland grab.Signed-off-by: Christoph Lameter <clameter@sgi.com>--- include/linux/page-flags.h | 41 ++++++++++++++--------------------------- 1 file changed, 14 insertions(+), 27 deletions(-)Index: linux-2.6/include/linux/page-flags.h===================================================================--- linux-2.6.orig/include/linux/page-flags.h 2008-03-03 15:29:48.734135117 -0800+++ linux-2.6/include/linux/page-flags.h 2008-03-03 15:32:05.200548999 -0800@@ -81,11 +81,16 @@ enum pageflags { PG_reserved, PG_private, /* If pagecache, has fs-private data */ PG_writeback, /* Page is under writeback */- PG_compound, /* A compound page */ PG_swapcache, /* Swap page: swp_entry_t in private */ PG_mappedtodisk, /* Has blocks allocated on-disk */ PG_reclaim, /* To be reclaimed asap */ PG_buddy, /* Page is free, on buddy lists */+ PG_mlock, /* Page cannot be swapped out */+ PG_pin, /* Page cannot be moved in memory */+ PG_tail, /* Tail of a compound page */+ PG_head, /* Head of a compound page */+ PG_vcompound, /* Compound page is virtually mapped */+ PG_filebacked, /* Page is backed by an actual disk (not RAM) */ #if (BITS_PER_LONG > 32) /*@@ -248,34 +253,16 @@ static inline void set_page_writeback(st test_set_page_writeback(page); } -TESTPAGEFLAG(Compound, compound)-__PAGEFLAG(Head, compound)+__PAGEFLAG(Head, head)+__PAGEFLAG(Tail, tail)+__PAGEFLAG(Vcompound, vcompound)+__PAGEFLAG(Mlock, mlock)+__PAGEFLAG(Pin, pin)+__PAGEFLAG(FileBacked, filebacked) -/*- * PG_reclaim is used in combination with PG_compound to mark the- * head and tail of a compound page. This saves one page flag- * but makes it impossible to use compound pages for the page cache.- * The PG_reclaim bit would have to be used for reclaim or readahead- * if compound pages enter the page cache.- *- * PG_compound & PG_reclaim => Tail page- * PG_compound & ~PG_reclaim => Head page- */-#define PG_head_tail_mask ((1L << PG_compound) | (1L << PG_reclaim))--static inline int PageTail(struct page *page)-{- return ((page->flags & PG_head_tail_mask) == PG_head_tail_mask);-}--static inline void __SetPageTail(struct page *page)-{- page->flags |= PG_head_tail_mask;-}--static inline void __ClearPageTail(struct page *page)+static inline int PageCompound(struct page *page) {- page->flags &= ~PG_head_tail_mask;+ return (page->flags & ((1 << PG_tail) | (1 << PG_head))) != 0; } #endif /* PAGE_FLAGS_H */-- | http://lkml.org/lkml/2008/3/3/594 | CC-MAIN-2016-22 | refinedweb | 578 | 55.95 |
- Type:
Bug
- Status: Open
- Priority:
Major
- Resolution: Unresolved
- Affects Version/s: 2.3.1, 2.3.2, 2.3.3, 2.3.4, 2.3.5, 2.3.6, 2.3.7, 2.3.8, 2.3.9, 2.4.0-rc-1
- Fix Version/s: None
-
- Labels:None
- Environment:OS: Ubuntu 14.04 LTS
Java: JDK 1.7.0_65, vendor: Oracle Corporation 24.65-b04
Gradle 2.2.1
OS: Ubuntu 12.04 LTS
Java version: JDK 1.7.0_72, vendor: Oracle Corporation
Gradle 2.2.1
When traversing a HashMap that was created from a parsed JSON file my unit tests start failing on Groovy versions 2.3.1 and later. There seems to be some sort of regression introduced.
To explore and debug this problem you may view my travis builds testing the latest versions of Groovy from 1.8.9 through 2.3.9.
If you would like to check out and debug the problem yourself you can do the following:
git clone
cd jervis
git checkout 2590bf2be5f8f2aaa1a25bcd63912506059da8c7
#passing build
GROOVY_VERSION="2.3.0" ./gradlew check
#first failing build
GROOVY_VERSION="2.3.1" ./gradlew check
gradlew check will automatically download Gradle 2.2.1, download the version of Groovy requested, assemble dependencies, compile, and execute unit tests.
[EDIT by blackdrag]
the issue can be reduced to this test
import groovy.json.JsonSlurper def jsonSlurper = new JsonSlurper() def object = jsonSlurper.parseText('{ "o": {"name":"John Doe" }}') assert object instanceof Map assert object.o instanceof Map assert object.o.name == "John Doe" assert object.o[null] == null
the code is confirmed to work on 1.8.9 and in several versions of 2.0, 2.1 and 2.2. It seems to start failing in 2.3 (first tested version was 2.3.1) | https://issues.apache.org/jira/browse/GROOVY-7234 | CC-MAIN-2020-16 | refinedweb | 295 | 62.95 |
Frankly, I don't think gamers are to blame. The gaming population 10 years ago was much smaller, now every grandma plays games. So millions of people buying mediocre games are not the main reason for these cheesy games. There's different demographics at work, and much greater temptations. 10 years ago you had gaming enthusiasts making games, now you have corporations.
You can compare this to the movie situation: studios versus indies.
Furthermore, in a mass market population, you can't come with top notch content and sell it at an average price without going under. Imagine Ferraris being sold for the price of Fiats...
So, you do the cheap part first, and maybe later on you can come up with some content.
Baldur's Gates' don't grow on trees, you know?
Edited 2008-12-21 21:54 UTC
Hear, hear! I have stopped playing games since the mid ninetees. I bought a Playstation 2 with some of the 'blockbuster' games, but I was completely bored with it after two weeks. The only game I keep going back to is Darwinia, which has a totally different feel and different gameplay than most well-funded games. Not surprisingly, it is developed by an enthusiastic indie gaming company. I can't wait until Multiwinia is released for Linux or OS X
As someone else who grew up with gaming in the mid 80s and 90s, I have to say the PS2, is the greatest games console to come out since the SNES. Games like Ico, Shadow of the Colossus, Beyond Good and Evil, Killer 7, the Persona series, Okami and many others can all easily hold their own against games from both earlier and later generations.
Baldur's Gates' don't grow on trees, you know?
>>IMAGE.
Baldur's Gates' don't grow on trees, you know?
>>IMAGE. "
I would not call this true, the funny thing is the gaming industry has gone the way of the mainstream, do not expect too much depth coming from the big ones, and I call Bethesta to be one of them. Although for Bethestas standard they have almost outdone themselves with Fallout (I cannot agree with the original post Fallout 3 has a lot of depth if you dont run through the main quest) anyway. If you want depth don´t look at Bethesta look at others.
Personal favorites since 2000: Arx Fatalis, which is probably Ultima Underworld 3, Gothic 1 and 2.
For RPGs, also I have to look at the Witcher we gets huge praise by many but others say it stinks, so lets see!
Also if you want real hardcore RPG the old style look at the latest Black Eye game Drakensang (probably Dragons song or son in the translation)
Totally! Wholesomely! Spoken out of my heart!
Words are not enough to express just how much I agree.
Now, it could be argued that the value of such a game isn't in its end sequence it's in the 100+ hours put into it. But as said in the article , that time was spent basically looking for something to do or happen.
Game developers should take a good look at the SNES era games, like Secret of Mana, Secret of Evermore, Chrono Trigger and all similar ones.
Granted they too followed mostly the same pattern and there was a lot of grinding. But they had boss fights that actually were hard and thus very gratifying.
But I guess the kids and gamers today just can't stand having to try beating a game.
Yeah, Chrono Trigger. I just was about to mention it, too. That was an awesome game with an complex storyline. A game I also like very much is Zelda: Ocarina of Time. A thing they both have in common is the really good music! If the game music annoys me I can't enjoy the game.
However, there is a relatively new game I like very much: Portal. Well, if it just wasn't so extremely short!
For me games should be like interactive movies.
Lots of story and not much grind or repetitive stuff.
So if a Game only lasts 6 hours (like Halo3), but the story is good and it has lots of content for 6 hours I am totally OK with that.
Playing a game for 140 hours is just stupid in my book. Insane waste of time.
And regarding the Xbox360: I got mine on Saturday and on Sunday I finished Halo3. Now I don't really need it anymore. All other games are not good enough in my book. And that frickin' thing is soo damn loud. Amazon is getting it back.
I want to play MGS4 on the PS3 now. Nothing else is good enough.
From TFA:
All quests in RPGs basically come down to "you are at location A, now go to location B, and grab object C. Oh, and there's a whole boatload of baddies between A and B"
Talk is cheap, game development isn't. If we game developers did what you say, we'd be bashed for "wasting the player's time with an averload of similar quests" or something like that.
I find pretty amusing when people say "X developer should've done this or that" because most don't realize how much work making a game is, specially a huge, open world RPG like Fallout 3.
And congratulations on your purchase, you'll have loads of material to bitch about
Thom,
maybe you expect too much of games.
I agree with you on all your points, but I still manage to squeeze loads of fun out of many of the games I play. Notably, Deus Ex (keep coming back to that game), Thief 1 and 2 (idem), and (more recently) Mount&Blade.
Mount&Blade is worth mentioning, 'cause it contains a shallow (if not nonexistent) storyline and a load of stupid quests, but it keeps me hooked
You have to have played this game to know the gratification of thundering over the battlefield on a heavy hunter, couching your lance and making Swadian Knight-sis kebab
Thom,
Try de Blob on the Wii, Metal Gear Solid 4 on the PS3 and Braid on the XBOX360.
de Blob was a breath of fresh air for me and MGS4 has all the storyline depth that you seek. The problem is that most of the this depth is connected with the previous games on the MGS franchise.
Have fun!
Edited 2008-12-21 23:11 UTC
I enjoy a first person shooter as much as the next person, but games with engrossing (at least moderately complex) stories will always come first in my book.
Too many rpg's these days just seem like work instead of fun. Some games like final fantasy usually (for me) have some form of payback in terms of story (plus the main quest is usually quite long...makes me feel as if I'm getting my money's worth). Far too many games have single player campaigns/stories that are too short and whilst one can have a heck of a good time playing with friends and online any sense of accomplishment quickly fades.
So basically I'll invest in games like FF and Heavy Rain, everything else comes from bargain bin.
p.s. Grim Fandango is the best game EVAR
Edited 2008-12-21 23:12 UTC
I'll second your complaint about too many RPG's seeming like work these days. Unfortunately, recent installments of the Final Fantasy series are just as guilty as any other (and I don't say that lightly as FF is far and away my favorite RPG series besides Fallout).
I mean, all that grinding and leveling up just to make sure you don't get waxed by the next boss can get really tedious. And I'm all for having sidequests but there has to be a limit to the difficulty; I don't want things so damned easy that I could do the whole thing blindfolded but, then again, a BradyGames game guide should not be a requirement for finishing a game, either. Clues or hints in which you have to exercise the mind for a solution are what I'm talking about here, not stuff that you'd never know existed without having to purchase a $20 manual.
Edited 2008-12-22 01:53 UTC
I think graphic and sound technologies have advanced rapidly in the past ten years - AI and plot resources have not. How exactly do you program a good plot? How do you make the computer anticipate a player's strategy and ratchet up the competition? I'm not sure.
I feel your rant - I was always disappointed with the real lack of coop capabilities in games. I don't understand why any of the Halo games setup a true survival mode - six players against waves of hundreds of aliens. But the problem is that above - computer AI has a limit. On the other hand, multiplayer does not - since we humans can learn new things, try new strategies, and challenge each other.
And another aspect is time and skill. At some point, does a game become less fun if it is too hard? Shouldn't a game instantly be fun to play, rather than requiring some amount of time invested? And so are you asking for games that anyone can play - or games that are for serious gamers?
The biggest thing that changed from the 90s to our era of games? You. Your age. (Mine too!) Yeah, you are 24 - you want more depth games. Congratulations for growing up. One option is to expand your interests beyond games and into challenges that we really face in the world. Games can still be fun to play, but life has pretty rewarding plots and challenges to face that go way beyond anything a computer could ever be programmed to do.
I agree that that both FO3 and Bioshock are lacking in some areas, namely content and story. However both games provide an amazing immersive experience and I think that was the main goal of the developers. That being the case, the people who prefer story over immersion are going to feel that something big is missing. Very few games have successfully delivered both immersion and a good story. Oddly, many of the games that do it right end up losing in popularity (Planescape: Torment, Omikron).
Being a PC gamer I feel that the release content of Fallout 3 is only the beginning. The community created content is what will eventually give the game longevity. Developers shouldn't rely on community development to make the game good however.
An aside: I have found myself spending more time playing retro games than I do modern games. It's cheap and their are plenty of games to choose from. I could probably spend the rest of my life finding great games from the 80s and 90s to play for the first time.
Edited 2008-12-21 23:24 UTC
You may like to say all wii games are the same, but they aren't, here's a few you may like:
-Mario Galaxy
-Zelda, Twilight Princess
-Metroid Prime 3
-Wario Ware
-And the best games to play wuth friends don't involve that much wiimote wanking: Super Smash Brothers, Mario Kart Wii, Mario Party Wii, Mario Strikers, etc..
"literate" PC/360/PS gamers often seem to bash nintendo brands because of "mario brand abuse" while forgetting that nintendo is definitely the favorite game studio out there amongst most gamers (even before the wii) and has the highest standard of quality.
Certainly it is true that those games are extremely well put together and are fun for everybody.
However I really would like to know if Nintendo would ever succeed in making a game purely for mature players, like FO3 or Bioshock. None of their games have ever had a particularly good story or depth of characters. In my experience I have always had superficial fun with nintendo games (not necessarily less just not something that hits me on many levels).
I get the feeling that nintendo stays in their comfort area hence the continuous rehash of their franchises
also:
"most gamers" depends on your definition
Edited 2008-12-21 23:35 UTC
What is a game for mature players? A game that has violence, gore, nudity, sex, religion, realistic firearms, etc? Being "mature" doesn't necesarily mean willing to see that kind of stuff.
Nintendo games are just for picking up, playing and having fun because the game mechanic is fun and creative to play, just by itself, and doesn't really "need" a complex story or mature themes to be fun.. you can find those in books or movies.
This is why they are the most succesful game studio (I'm not even talking about being hardware vendor), as they gather gamers from all ages.
Actually I would call that kind of game games for the male teen crowd. There is a time in life of ever male teenager when this stuff matters it usually is the time between 13 and 22 later this stuff does not matter but it is not an annoyance either.
So putting as much violence and gore into games is definitely not making them for an adult audience it gathers more to teenage guys who find this stuff cool (because it is cool for them due to being labeled being adult and due to the testosteron level they have :-) )
I am in my late 30s and already way out of that phase and I personally have a different feeling of what I would consider a game for an adult audience. For me an important story, a good setting, excellent non repetetive gameplay mechanics are the most important stuff nowadays!
Back when Final Fantasy was made for the Nintendo consoles, those games had a certain degree of "maturity" about them while maintaining a sort of family-friendly atmosphere. In my opinion, Final Fantasy III had one of the best storylines (and scores) in all of gaming history, though I didn't have the patience (and probably skill) to beat that game without cheats. And I'd say also that the Zelda games have always had a good storyline, not been some sort of surface, superficial game, and had some sense of maturity about them that other Nintendo games lacked. I've played a few of the Wii games, though, and aside from Twilight Princess, the ones I played (Mario Kart, Smash Bros., and some Sonic game) all seemed not very well put together and rather boring. I'll still try them out since I've only played very little, but I'll not be buying one anytime soon. I'll be sticking to the Game Cube and my old SNES emulators for a while, assuming I ever get time to play them.
Edited 2008-12-22 19:49 UTC
They did, the metroid series is probably the perfect examples.
Btw. I personally hate if mature always is connected to extreme violence and gore.
But if you want to go to that extreme: Nintendo has released a Survival Horror game on the cube and to my knowledge another one is in the works for the Wii.
But this is simply not their main stuff, their main stuff is family friendly stuff, that does not mean it is not hardcore to the ground, which in many cases it is!
I think wii sports is the best game ever. We were able to teach our 4 year old niece how to use it and she can now throw 'strikes' and 'spares' in bowling. I can play baseball during the winter. It really is the virtual reality.
I don't like using a controller; would much rather use a mouse and keyboard.
Try getting Omikron: Nomad Soul. It's a PC/Dreamcast game from 1999. You won't be disappointed. Storyline, immersion, great soundtrack (David Bowie as in-game music band!). Just the sound of opening metal doors made shivers run down my spine. It's that good.
Btw, you could have warned about the Fallout 3 spoilers, I'm only 45hrs into the game!
i agree, and try Fahrenheit too (rel. sep.2005 known as Indigo Prophecy in the United States and Canada), comes also from "Quantic Dream". It doesn't have much diviation but game does change according to your actions, and u can even have sex with ur ex-girlfriend, if u do it right when she comes to pick up her things, yammi 8)
Wow omikron, that game got such terrible reviews. I remember because I got it as a present from someone and immediately looked it up and thought it would be a terrible game, but reviews can be wrong like it was for fall out 3.
While I did have a blast in fallout 3 it was nothing compared to playing Oblivion or Morrowind. The quests were not there the end game wasnt there, there was nothing to keep you playing after you finished it, nothing. I tried and tried to do things after I beat it, but it had nothing to do.
If you really really do want to have a blast in a game with tons of side quests I suggest you pick up oblivion, even though most rpg fans think of it as a bad game because of the way leveling works(mobs level with you). The amount of fun quests are way out there. For example there are quests to be a theif, a mass murder, a wizard, a knights just about anything you desire even being a gladiator.
in the article.
It is Commander Keen!
heehee
:b
Your right games lack any real depth. My brother wonders why I play Car racing games. I only do that to get my gaming fix.
I feel time is wasted if you expect and an adventure and it doesn't deliver. In saying this, I feel the games you described like Fallout 3 are made to look like they are for an adult audience but are really made for teens.
Edited 2008-12-21 23:36 UTC
I always was saing (long before Fallout 3 by Bethesda) that this will be shit, something like Oblivion with Guns(TM) and nothing more, unfortunelly I was right..
You probably remember them because Baldurs' Gate I & II were out in '97/'98 when a lot of us were already out of university degrees and working in the field(s) and/or married.
Well, I'm 24, same as Thom, I got my university degree about a month ago
That explains it. I was suffering as a consultant working at ATT Wireless when those games were released.
Which is why I'm going for games driven more and more by player interaction and less by the environment, i.e., PvP MMORPGs. Right now I'm playing Warhammer Online because of its PvP focus, and I'm waiting for Darkfall's release because it completely does away with such things like questing and leveling and brings MMO PvP to a whole new level along with a new physics system. I also like to FPS multiplayer games although I'm currently not playing any and looking for some good ones (any suggestions welcome!).
On another note Thom, you should give Wii games a try - they still have the classic rewarding and fulfilling feeling of a game but with excellent graphics and sounds.
To a large degree, I sympathize with Thoms views on today's gaming. I think, Merkoth was a bit harsh retorting up there, as I can't see any reason why not to be dissatisfied with gaming affairs these days. Yes, gaming is a huge commercial enterprise, bigger than movies, but there's no reason why gaming should follow in the footsteps of the movies business. At least, the 'Powers that Be' of movie makers [think Big studies; Management] actually has a sense of how diverse peoples tastes are, and will gladly support a 'narrow' film.
Now, we must understand, making games these days is seriously ressouce-demanding, in terms of manpower and manhours. This is mostly due to the fact that Graphics have become so incredibly more complex and advanced as opposed to graphics in games 15 years ago - and so need far more work to fulfil the expectations of gamers today.
The reason I mention this, is that in my opinion, the complete gaming business is completely graphics driven! People are getting better and better graphics for their PCs and their Consoles, and the work needed to produce game-graphics which will satisfy peoples investments into better looking PCs and consoles, is escalating. So, naturally, the gaming studies and especially publishers, want to make sure, they can cash in on a new game, as each game published represents a HUGE investment, which they want to secure a proper return on.
So, whenever a game publisher and -studio decides to produce a game, gameplay and 'intelligent' content is gradually toned down, the pre-release 'hype machine' is all about how fantastic the game will look (" Yeah, i've got this new $399 graphics card | this new $499 console, I can now justify spending 50 bucks on this new game!]. Gradually toned down to the point of none-existence, because it simply DOES NOT SELL - at least not in the minds of the game producers.
Actually, The Wii tried to remedy this, but not many gaming studios are geared towards that kind of thinking (where gameplay/having fun is above beautiful graphics), and so it seems to have failed. Yet, it sold - and is still selling - very good, because of that very promise of letting people 'simply have fun playing games'.
In essense, my point is, that most gaming studies are soo hardwired culturally and productionwise to producing games with high visual aesthetic value that making good, fun, lasting games a bit more challenging than the typically empty shoot'em ups seems very hard and outright ridiculous.
Yes SOME (the vast majority stink to high heaven) of the wii games are fantastic. But to me they simply lack the depth that I'm accustomed to from earlier (Deus Ex) pc gaming, even xbox360 and the ps3 are dumbed down, but not to the level of the wii. For serious gamers the attraction to the wii is less to the platform but more to one or two games (mostly those by nintendo).
I agree on most parts, BioShock had a very poor story and athmosphere, nothing compared to System Shock 2. Fallout3 in contrast has a very good athmosphere, a lot of potential for exciting stories in cities like Megaton and Lamplight Caverns. In addition, the game got much too easy in the end, with tons of perfectly repaired weapons, Tesla armor and companion. The end is too easy and experience points are 'Max'(?!?!) long before all attributes are maximized.
Oblivion had a lot more quests, also some more complex ones.
I find it interesting that you included Full Throttle in your list of "games you grew up on". I thought Full Throttle sucked. There were no side quests, and the main quest was entirely too easy and way too short. It had no replay value, and it took me less than one day to beat the game.
Definitely would not go on my list of good adventure games.
Oblivion's main quest was a little short, I agree. But there are tons of side quests. Like the Mages Guild, and such. And if you find it too easy, just crank the difficultly level up. I assure you that if you crank the difficultly level up, you will really need to be careful playing the game
Also, Morrowind runs under the XBox emulation on the 360, and was quite a bit better than Oblivion as far as the story lines, the number of factions you can join, etc. It's also more difficult as you don't automatically recharge magicka and such in Morrowind like you do in Oblivion. When it's gone it's gone, and you only get it back with potions or by resting.
And of course, if you really want hard core, ADOM and Nethack are free, and run on virtually any hardware no matter how old.
Edited 2008-12-22 00:41 UTC
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A good and valid point, and I don't disagree. But I also think the really good interactive-fiction games were almost like good novels; you would enjoy them, put them on your shelf, and then go back to experience them again some time down the road.
Unless, of course, it involved poor Floyd in Planetfall... That scarred me in my developmental years almost as much as Disney's brutality towards Bambi's mother or Old Yeller...
.
Actually I liked Gears of War which you described as a "mindless shooter". Just because you didn't like it (or haven't played it yet) doesn't mean that it's "mindless". There's a reason it was the top selling game for XBox 360: People liked it and I think that's what matters in the end. Game Studios aren't out to satisfy just your needs neglecting what millions want. And actually the game did score highly positive reviews on most gaming websites and that also might mean that most hardcore gamers approve of it.
GOW is a good game, but not a great one. It has some interesting storyline and minor plot twists and they managed to do it just right to keep even non-FPS fans interested long enough.
It's not a cult title tho. It's nowhere near System Shock (either one) for example (yes, different genre, but both can be seen as FPS).
I mostly agree with Thom, today's games lack character in most cases. You can "feel" the commercialism behind them, the "we're doing this coz the boss said so" approach. Games like Ultima Underworld [2], System Shock [2], Baldur's Gate or even Morrowind had "it".
I think the "it" is the extra piece of love from it's developers. Like the endless supply of mysterious historical puzzles in Morrowind, or the fabulous movement and physics system in System Shock 1 (leaning, laying down AND body physics in 1994? WOOT? Doom is teh sh*t!), or the great NPC interaction of Baldur's gate ("Evidently so..").
Arguably the last great game for me was Morrowind, although I must say Shivering Isles had something special as well.
Edited 2008-12-22 07:19 UTC
That is the truth games now a days, are so boring it is harder to find a decent game. I hated when "Working Designs" folded but some of those people went into Atlus. So now more good games are coming from them. I remember the games Wing Commander 3 and Wing Commander 4 which your choices really did affect the outcome of the game somewhat.
I'm not a huge gamer. The only two games I've ever been really into being Neverwinter Nights (I used to be really big into D&D, NWN satisfied my urge for such things) and, more recently, Half-Life 2. I found this game to be spectacular. Not because it was open ended, and of all the "choices" you could make. Because it had solid gameplay, and a structured and compelling plot.
More to the point. Open ended games SUCK. They get boring quickly, which anyone with an I.Q. higher than 30 who has played Grand Theft Auto will tell you. Maybe they can be good, but it would take some incredible game design that I just haven't seen.
I have to disagree. Seeing you focused on Fallout 3 I'll stick to discussing that. Some very minor spoilers ahead (although you did spoil the ending sequence.. so ..whatever).
While you cite that there are just 17 side quests, you don't note that some of these are only available to bad people, and some to good. Further still, there are far more "quests" than that in the game, but they are, as you say you wanted, simple errands for NPC's. A very early example: before you leave the Vault, you are asked to save a character's mother. If you do it, you get experience, and a special item - it is basically a quest. But it's not called a quest because it's so short. The only experience you get is from killing things you wouldn't have otherwise found. There's a suicidal man in Rivet City. You can talk him down if you want. There's a polygamist who holds phoney elections in an isolated town. There's a town of cannibals. There are broken pipes in Megaton. There are a ton of little stories lying around, all of which would be the equivalent of a quest in the old Fallout games, but they are not numbered amongst the quests. By saying there should be lots of little NPC errands, and then only mentioning the number of tasks big enough to actually be called "quests", you've created a false impression over how much there is to do.
I will admit though that there definitely didn't seem to be 140 hours worth of content. The main quest can be finished in about 20 hours - I got my fill in 40 and checked out as soon as I could no longer find specific side tracks to explore, because once you hit the level cap killing creatures loses all value.
"If a game's good/evil thing were to really have any effect, it would mean that being good unlocked different quests and items than being evil."
Here's an example of this exact demand in Fallout 3: You can complete a quest to free the slaves at Paradise Falls and kill the slavers there, or you can join them and become a slaver yourself. This decision effects how you gain access to Little Lamplight, it effects how all the kids in there regard you, and it effects whether the escaped slaves living at the Temple of the Union will give you the time of day. Given that there are specific quest threads associated with the Temple of the Union and Little Lamplight, how you deal with Paradise Falls effects your play experience in a divergent way. It is simply inaccurate to say your actions have no effect on the content in Fallout 3.
Another example is the bomb in Megaton. You can disarm the bomb, or, if you're a bad character, detonate it for lots of cash. In this case, you lose access to a couple of quests, characters, and leads on your main quest because of your decision. If you disarm the bomb, you get a house in Megaton, and the goodwill of its citizens (who give you gifts). Again, it is simply false to say there is no functional difference between these outcomes.
The dialogue is tied to your karma, meaning that people treat you differently, and your actual options for speaking to people change, based on your actions. If you play the game as an evil character, NPC's will treat you differently than if you are good, so you will not go through the same dialogue. There are bad people and good people in the game, and they won't treat you the same way no matter which way you swing, it's that simple. Your opportunities to enlist cohorts are also tied to your karma. A character in Megaton for example, is a bad person, and told my character that I was too much of a good person to travel with. Funnily enough, it turns out he'll only join an evil character. Other cohorts have similar requirements, and that makes three specific examples of your request. There are plenty more but I'll move on. My suspicion is that the game flows seemlessly enough that maybe you just didn't notice the degree to which you were responsible for your own experience.
In complaining about "modern games" specifically you seem to be speaking nostalgically about old games, as if they were completely free from the constraints of computing power, and it used to be that every NPC had a life story they could recite on command. You need to keep in mind not that only is there a ton of divergent dialogue in Fallout 3, but also that every single line in the game has been recorded by an actor. Bethesda claimed during development that there are over 40,000 lines of dialogue in Fallout 3. Now, I wasn't counting how many lines I heard, but I wouldn't be surprised if it was about a third of that. Apparently Fable 2 has a similar amount, with about 45,000 lines of spoken dialogue. This is not what would typically be described as a lack of content. Complaining that developers only managed to fit about a day and a half's worth of characters talking into their disc, however, could probably be described as "spoilt" or "whiney".
By comparison, older RPG's usually had a few thousand lines each, Fallout 2 had approx. 2000 lines of dialogue, while Baldur's Gate 2 had about 3000 lines. But I wouldn't say these games lacked content either - they were great too. In any case, it is not the case that modern games have less content compared to older games from equivalent genres. Typically the opposite is true. But I'm not sure if you were complaining because you think old games were better, or if you were just complaining because nothing is ever good enough for you.
So not only is there a huge volume of content in Fallout 3 in comparison to older RPGs, but replaying is in fact necessary to see all of it. That addresses two of your complaints - your remarks about gratification are mostly subjective measurements, so I'll leave them be. However, the way you've described "the final quests" seems to skip straight to the ending sequence, and omits the difficult fight at Raven Rock right before it. That seemed to me to be the climax of the game. But maybe you managed to talk your way out of that fight. That place happens to be yet another instance where good/bad characters have access to different outcomes, a feature you claimed was a gimmick with no functional effects on narrative. Sorry, I felt that needed repeating.
The weirdest thing about complaining about Fallout 3 specifically is that you seem to be aware you're demanding a high spatial density of content across the map of a post-apocalyptic wasteland without a hint of irony, as though such a place should be teeming with life and opportunity. These games are set in a world still completely ruined hundreds of years after a nuclear war, full of mutated creatures and people, practically everything is irradiated, and practically everyone is sick with radiation poisoning; everyone is scrounging, scavenging, starving, using broken equipment, bartering or using bottle caps for currency, enslaving people, killing people, in some cases eating people, and you're like "So what do you guys do for fun in this hellhole? Jeez, what a drag."
Edited 2008-12-22 04:08.
Edited 2008-12-22 17:35. "
Actially from the usual standards of Bethestha Fallout 3 is excellent. Bethestha is one of the companies which gets better every game maybe in 10 years they will reach Bioware level and in 20 Black Isle level :-)
But seriously. Fallout 3 is a good game but it is probably not the game people expected, well it is hard to fill the shoes of probably two of the most beloved RPGs ever. For some strange kind of reason Bethestha did not hire the original team which applied for a job for Fallout 3 at Bethesta to work further on their baby. That probably was the biggest mistake in my eyes for the game.
During my second undergrad in CS a friend moving on to a Neuroscience Ph.d, a friend from my M.E., field and another friend in Physics all loved them.
Hell, we even had an English major for a roommate who got a kick out of it and we would work together and solve the puzzles with girls and friends who came over for what we always called, "prefunctorials."
Of course, we also played a lot of DungenQuest and my best friend who was an Artist designed an expansion that took an average game of 2 hours to 4 or 5 hours.
There always was the various parties to crash and bars to shoot darts and whatnot, but there were plenty of hours spent with games that carried you off into adventure.
DOOM, Quake and the rest get freakin' boring, very fast.
I grew up on Kings quest and other such games (summer games, load runner, etc) on the apple IIe.
I remember when streetfighter II came out on the SNES I thought to myself "man, a came just CAN"T get better than this".
Fast forward to now. I have an xbox 360 which I enjoy using but I don't use it that often. The only game, that blew me away was Elder Scrolls IV: Oblivion, also from Bethusda . That game is pure escapism bliss. You can make moral choices, which I suspect don't effect the main quest but they do affect the sub-quests (of which there are seemingly hundreds).
Anyway, I pondered the fact that I was no longer into games as much as I used to be. Eventually, I came to the conclusion that I'm a bit older now and gaming just doesn't have quite the same appeal that it used to. The games of old we remember so fondly are only good in our memories- don't go back and play them again, trust me....
Lastly, some very good and rather funny articles about gaming that originally appeared on pointlesswasteoftime.com...
Exactly.
This is the reason I (usualy) don't buy games.
I have some gamer friends, and if i want to play, i come over. Today's games cost to much and offer little in return, i don't care (much) about graphics and sound, as long as the gameplay is good.
My most favorite game to this day is Super Mario World
It's a game you can play over and over again.
Really i think the wii is great, my favorite games are tennis
)) and Mario Galaxy, and ofcource, games like SMW, SMB etc... (old nes/snes games).
This topic has much to do with (movie, game) piracy
People don't want to buy games only to find out that the game is sh*t. The same goes for movies.
Some games i like/would really recomend:
Metal Gear Solid 4 for PS3 (and Metal Gear Solid 1 to 3)
Braid for Xbox360 (and hopefully soon on PC)
World of Goo - i really downloaded this game from piratebay, and after a few levels i found this game to be really really good, so much good, that i could play it over and over again... so i bought it. ( still waiting for a level editor and level packs
then there's LineRider 2.
And, maybe* GTA 4
PS: Quake 3 is the best online shooter still.
It's easy to think that when you buy a game,you are buying something that belongs to you: one good game, your game, a game you can play forever.
In fact that's the last thing you're doing. In reality you are making a down payment on a franchise rental. No company can exist selling one-offs. A company needs to get you on the upgrade crack pdq, whether it be more games in the series or on that platform or from that maker via their proprietary download system; or more hardware, newer graphics cards or mice or controllers, online gaming fees, whatever. It all adds up to be surprisingly expensive. But then the gaming industry these days is huge and the hardware makers want a return from all the money they invest in gaming, too. They want your money and they want it now.
So games aren't designed to last or to be the best. They are designed to be good enough for long enough, maybe six months or so. Add to that the humongous cost of developing a game these days, and there's even less chance of a truly original off-the-wall number. Developers have to stick to safer ground in the mass market (aka the moron market) to ensure a large enough audience from which to recover costs.
There's nothing unique about this. Most other industries work in the same way - cars, white goods, electronics generally, fashion, et al. Call it capitalism. If you want something truly different, then sell up, do without modern technology, build your own pub so you can entertain yourself at home, and learn to play the ukelele.
Fallout 1/2 was the best RPG is the best RPG and will be the best RPG.
Game developers now only care how to push DX x (x>=10) to limit not about game. Nowadays there is no RPG there is no turn-based games. We have only lots of FPS games with some nostalgic elements from other genres.
ONLY one new game really worth playing from huge number I tired is S.T.A.L.K.E.R. Sad.
I put all my hopes about future gaming into Blizzard: Diablo 3 and Starcraft 2.
I'm quite surprised no one has mentioned it yet, but if you're looking for an RPG with an immersive storyline and plenty of interesting quests, may I suggest you give Mass Effect a shot?
It's rather good, the first I thoroughly enjoyed playing (and was sad to finish) in quite a while. Soon after finishing it I played Fallout 3, and I can say that I didn't enjoy it anywhere near as much.
Perhaps it was the big void in decent games prior to coming to Mass Effect, but it was quite a relief to find a decent game to play after all this time.
I'm planning on buying it today (assuming its price is acceptable). Keep an eye on my blog [1] if you want to know how I feel about it.
[1]
Edited 2008-12-22 12:39 UTC
I recently decided to buy a Xbox 360. Not because Wii is not a great console, but I know I will like to play damn big complex games and Wii is obviously not the right machine for that (though success of its control system must be acknowledged. That's just a different kind of machine than Xbox and PS). I never bought a console because I liked to play PC-type games (two different kind of games). But got tired to keep up with my PC upgrades to play as I wanted to use a notebook for both work and personal matters.
Bought that version with Gears of War 2 bundled and didn't regret that. GoW 2 is basically amazing. It's a very hot game to play with lots of damn hot graphics (I'm enjoying it in HD mode). And gameplay is not that limited when compared to other titles.
However, I know I'll miss PC-type games. I will never be the usual console gamer (and bought Command & Conquer 3 to take a breath of fresh PC-era games...). Many games are graphically impressive but poor in gameplay. However, I guess the trick is to try to switch genre sometimes. For example, from GoW 2 to Last Odissey: two different kind of games.
It's a known fact, however, that console games have a different target than usual PC games. And it's a known fact that today most games try to achieve superior graphics because that matters.
However, let me say one thing: anyone who played Monkey Island saga or Populous or Sim City, knows very well that time 7 games out of 10 being released sucked. I mean, they were completely useless piece of garbage.
Average quality is much better now and I'd say that 8 or 9 games out of 10 being released can provide a few hours of fun. Quality improved a lot and while we don't have such a quite good difference among games we enjoyed in 90s (most console games are basically the same gameplay brought to a different, and usually weak, story...), I'd say that most of them can provide a few days of fun.
Of course, when you play 10 hours per day everyday, you will soon find yourself finishing all games very fast. But that's not my case.
I'm a good deal older than you (48), so I have had the feeling you express for longer than you. My best gaming experiences were on my BBC micro and some old PC games (such as Masters of Orion 2). Newer games have much more eye candy, but not much more game. Modern RPGs don't really differ much in gameplay from Angband or Colossal Cave, but have replaced ASCII graphics and text with 3D graphics with animated blood-splatter.
That said, I have changed too. I used to spend countless hours playing Elite on my BBC, but trying it again now doesn't bring anything like the old feeling: I can more easily see the limited scope in spite of the huge game world. But Elite was made on an 2MHz 6502 with 32KB of RAM, of which 10 KB was used for the screen bitmap and a couple more for the OS. Compared to this, the scope of Elite was huge. With more than 10000 times as much RAM, huge disks and fast CPUs and even faster graphics cards, you would think the scope would grow. But it seems like all you use the extra space and power for are graphics textures and soundtracks.
I know that content takes time, but when you consider that Elite was made by two people, why can't teams of dozens of people create more content? Maybe game companies hire too many graphics and sound designers and too few story tellers? Even when games are made from movie titles, the story in the game is typically radically simplified and more repetitive, in spite of the fact that you will tend to spend more time in the game than you do watching the movie. And I'm told that making a major game costs more than making a Hollywood movie -- even an animated movie. So where does all that cost go? Not to AI, which typically sucks. I know that a good AI is hard to make, but with the budgets major games have, it could be much better. Also not for story lines or freedom of action, as this is typically limited as well. There are too few meaningful choices in games: Either a choice doesn't matter at all, or you die immediately if you choose incorrectly.
Now, I don't claim I can do better. My speciality is in programming languages, and though I have done a bit of game design, graphics and AI as well, I wouldn't be hired by a game company for these limited competences. But game companies should be able to cherry-pick the best talents in these areas. But only the graphics seem to show.
I'm a hardcore Nethack and Collosal Cave player and find Fallout 3 a masterpiece.
All past time wasn't better, it just looks better. If you think Fallout 3 isn't that good, I could recommend famous, game of the year titles that would change your mind by mere comparison; titles from 2008, 1998 or 1988.
Well I think one of the problems is that creating games takes so much money and time now. Compare that with game-developement just more than 5 years ago.
This is one of the reasons some very large companies have evolved with all their mechanics (how they work).
I myself like to play "clever" games from time to time but also enjoy the brainless games --> instant fun.
Imo one of the best games ever and one of the few RPGs I actually played through and watched the long outro is Anachronox. Great story, fantastic dialogs, great locations and great story and these dialogs (eg. when they are stranded in their ship).
It's a pity that there won't be an Anachronox 2 while I'm bombarded with the nth Call of Duty title.
Other games that are really fun are imo Psychonauts and Beyond Good and Evil. Planscape Torment is good, but was too time consuming for me.
What I don't like though if games act like if they have a story but don't provide you with information. You are left with a lot of questions and the feeling that you missed some videos that explained stuff. A lot of the "current" (in my time span the last few years) adventures I played do it that way like Broken Sword -- even more than the old titles.
Yet I have to say that out of the 100s old games I have I would say that less than 10 are really great, basically similiar to the situation now. Maybe we simply (only) got older.
Not sure about where you purchase your consoles, but in the end, the PS3 tends to be cheaper. The PS3 sells for $350, but includes a Blu-Ray player, no online tax, 40GB hard drive, etc. It allows ANY Bluetooth device to be paired with it (keyboard, headset, mouse, etc), any hard drive to be connected (unlike the Xbox which requires Mircosoft's $100 20GB hard drive) and such. The Xbox is more modular than the PS3, yes, but these are common things that lots of people get anyways. Why restrict what hard drive you can place in your console or restrict what devices you can pair with it? Thats' right, they need to be Microsoft branded which means paying an arm and a leg for.
I thought this needed to be pointed out, as many people fail to notice this.
I don't really play games all that much and when I do it, it is mostly those simple time wasters or some old classics on emulators for half an hour or so. The genre that I like the most - fighting games - is not as popular as it used to be and with SNK folding, the best fighting game series of all time, The King of Fighters, has not received the love that it deserves. Playmore did a good job bringing it to 3D, even keeping some of the touch that made the original series so amazing, but there is something to be said for good 2D sprite animation that simply doesn't translates that well for 3D.
I still play its newest versions on the PS2 though, but I prefer to run the earlier versions - KOF94 all the way through KOF 2003 - using emulators on the PC (GnGeo rules!).
When I'm playing on the console I really enjoy simpler games. The Guitar Hero series is a huge hit at home. My wife and my 6 yrs old daughter are addicted to it and the 3 yrs old daughter is starting to show some interest...
When we're not playing that, we like car racing games such as Burnout Revenge, or a classic fighting game such Tekken 5 or Soul Calibur 3 and recently I started to enjoy an adventure game called Shadow of the Colossus. Now that's a great game!
It doesn't take more than a PS2 to keep me entertained and I'm pretty sure that I'd love to play with the Wii. I will grab one as soon as it enters my affordable price range...
Having said that, I'm really looking forward for the latest incarnation of the Street Fighter series on the PS3 and the XBox 360 and since future releases of Guitar Hero will be exclusive to these consoles leaving the PS2 out, I will have to consider putting down the money to get one of them sooner or later.
Seriously, thank goodness for emulators. Just dug out my mame fighting game collection I had stored away on an external hd. Ah man, nothing beats some serious fighting games, KI and KI2 along with all the early MKs and of course, Street Fighter (SFA series is the best, imo).
Reviewer buys single player games and wonders why there's no unlimited replay value.
Reviewer then mocks two of the most popular multiplayer game series that are known for their replayability and finely tuned control mechanics, citing lack of innovation.
Don't quit your day job.
I understand about Bioshock. 50$ (at one time) 10 hours to complete... and no replayability... your point works here, but....................
You people are spoiled. 100+ hours of gamming and you're bitching about it. WTF? It can't be your girlfriend. Did you play commander keen for hundreds of hours? Really? You're just pissed your drug has run out. Go back to your dealer and pick up Oblivion. Also, if you had gone the PC route, you would also have access to user created content. (Hey, your PC might be able to run NWN or NWN2.) Or maybe your should do some multiplayer games... WOW or maybe a MUD would be a better fit for you.
Also, if games were so great back in the good old days, go replay them... sometimes it's fun to kick those games around for like 10 min... then you remember why you moved on. (sorry, singleplayer text games suck) You're never going to drink your first beer or have sex for the first time again. (ok some of you have yet to get laid) It's like saying the internet sux cuz you don't stay up all night on it like you did the first time.
PS Your reward was 140 hours of entertainment for 64 Euros, not a slideshow.
> then you remember why you moved on. (sorry,
> singleplayer text games suck)
Do novels suck compared to films? Because they are "text only"? Damn, you are narrow minded. Were you even around back during the days of text only games?
Single player text games DO NOT SUCK, as long as they have a decent story line, decent plot, and are engaging. God forbid you might actually have to use something called "imagination". You know, that's the thing we used to do before 1080p 3D graphics and such, when we actually had to imagine what the world looked like. After thousands of years, text and imagination are still a fine medium to communicate an awesome and engaging story--one that is often far more engrossing than any amount of 3D graphical wizardry can be.
What DOES SUCK most of the time though, are typical multiplayer online games. I'll take an intelligently designed computer controlled NPC over a sub-intelligent online gamer kiddie typing things like "1 pwnd ur @$$!" any day.
There are too many jerks in most online gaming communities, and it ruins the experience for me. So I rarely do it and prefer well designed computer controlled NPCs instead--even if those well designed NPCs only interact with you in text mode.
Edited 2008-12-22 17:31 UTC
"Do novels suck compared to films? Because they are "text only"? Damn, you are narrow minded. Were you even around back during the days of text only games?"
So you're using a text based browser then. Good for you, less exploits.
(edit- added the quote at the top)
Edited 2008-12-22 17:50 UTC
That's comparing apples and oranges. And here's why. With a browser, I am often getting news about the REAL world or something. So then pictures of real events that actually happened are important. In an adventure or RPG game however, that is not usually the case. It's usually a fantasy world that doesn't really exist in reality. And so sometimes text only is the best way to convey it since it leaves the visualizations up to the player or reader's imagination.
And I find it interesting you quote a question from my post, and then instead of answering the question, you change the subject.
So do novels suck compared to film? Do they? Because they have no graphics?
(edited to expand more on why it's apples and oranges)
Edited 2008-12-22 17:59 UTC
> Your question is a distraction... misdirection,
> we're talking about games. Lets compare text
> game sales last year to graphical games.
It's not a distraction at all. And you might want to take a class on rhetoric. Since what you are doing right now is a classic example of a logical fallacy when it comes to argument. You are avoiding a legitimate question by attempting to change the subject.
The reason you are avoiding it is obvious. Because you can't answer it in a way that would support your original argument without making you look like a fool.
Do novels suck compared to films cause they are text only? Do they?
You are avoiding this question like it's some kind of plague or something. Why can't you answer it?
I got Fallout 3 for the PC when it was released. It's graphically gorgeous. The character creation is novel and fun. The first time. The third time, it's a little tedious. I think that sums up the game pretty nicely, which is sad. Anything you do the first time is cool - but after the third time, it's becoming rote and boring. All raiders look and act the same, and they all have the same lairs. Are they a cult or something? I thought they were opportunists who were a little low on social responsibility, not some frigging Chaos cult from Warhammer 40,000.
It might be billed as an RPG, but it's not. There's no role to play - if you're a messianic do-gooder, you get a couple of different options, and a group of mercenaries who occasionally track you down and try to kill you. If you're a Vault Boogeyman, you get a couple of different options, and a group of 'regulators' occasionally track you down and try to kill you. What's the difference?
When I get a house in either Megaton or Tenpenny, why don't I even get a dialog option to offer any of the NPCs a place to stay? Why is the limit of the affection of my 'spooky girlfriend' in Bigtown her giving me random gifts of junk, instead of what she was hinting at? Why is it when I pay a prostitute in Megaton 120 caps, I don't even get the goofy Fable "oohs and ahhs"? I thought this was a 'Rated M for Mature' game? My girlfriend was carded when she bought me the collector's edition, for Grod's sake. I thought 'M for Mature' would allow me pull the same kind of BS that I did in Fallout 2 - seducing the drug lord's wife in New Reno, that sort of thing.
The 'ownership' of junk in the game is another ridiculous notion. Say I kill an NPC, for example, Lucas Simms. I get the key to his house from his body, but I can't sleep in his bed, because he "owns" it. I get a karma drop for stealing his stuff. He's dead! And for that matter, what is up with the NPCs whom you can't kill? I can't kill his son, who still talks to me even though he watched me shoot his dad in the back, because apparently that isn't covered in 'M for Mature'. Before I torched Megaton from Tenpenny, I walked through the town and killed every person I could see. I couldn't kill Moira, because apparently she has to survive in case you ever go back to Megaton to visit the highly-radioactive crater. In Rivet City, there is a boatload (pun definitely intended) of NPCs you cannot kill. What is this crap? I thought my actions mattered? Aside from the random kill teams of mercenaries/regulators who are pursuing me for being too good or bad, my behavior has very little impact on the game. Oh, people's little vocal blurbs are different when you walk past them, but the actual dialog choices are the same, every time.
Honestly, I wish Bethesda had focused more on lines of text dialog, versus all of the spoken dialog. Perhaps they could've included more interesting content that way. Lady Killer or Black Widow should've opened up some really interesting dialog with NPCs of the appropriate gender. Instead, it's just a bonus to kill the opposite gender, and a couple of heavy-handed options in very few dialogs with a couple of NPCs.
And speaking of railroading - once you actually get into DC-proper, you actually have very little choice in how you get to your destinations. You can't just slog overland through groups and groups of Super Muties, if you so desire. No, you need to go down this subway, and connect with this other subway, and then walk through this plaza, and then down another subway, etc. Bullcrap. The wasteland area is full of openness, but the DC Metro area is absolutely not. You definitely are following a route (which your map helpfully shows you as you wander through the maze) that is designed to keep you 'on-track' for the main quest. The dialog with the NPCs is horribly limited, very clumsy, and frequently references situations you haven't encountered yet. Aside from the selfish use of skills such as Repair, Medical, Barter, etc. There isn't a whole lot you can do with them. I thought this was an RPG - why can't I repair people's broken equipment for money? Why can't I become a trader through Canterbury Commons? Why can't I charge people for healing? My only option for profession is being a stone-cold killer. Every other skill exists to enable me to do that job better.
Fallout 3 is a bastard hybrid of FPS and RPG, and it's no good as either. You can't play it as a shooter, without becoming frustrated as hell (even using VATS: are you going to tell me that you honestly think a raider should take 3 head shots from an assault rifle?), and it's not an RPG by any stretch of the imagination. I think that Fallout 3 could be a great framework for some awesome RPG building, but it certainly fails in its current form. It looks like it's going to be immersive and deep, but after only a few hours of playing, you realize it's incredibly shallow.
You, sir, get it.
Fallout 3 is absolutely awesome. However, it could - and should - have been so much more. The potential for depth and story and possibilities is oozing out of every NPC, every location, every building, yet most of them have little additive value to the game.
And that's sad.
Edited 2008-12-22 17:08 UTC
Because it's no more an RPG than most RTS have anything to do with strategy ("build-build-build-assault.", Command & Conquer how a loath thee).
if you want to play a game with good story (these are going ot be older games) ejoy a few recomendations.
Breath of fire 3
Shining force 3
xenogears
Star Ocean: Till the End of Time
Final fantasy 7
those are just a few but that should keep you busy for teh next month
Edited 2008-12-22 18:19 UTC
I like your review overall. I think there is a lot to be said for the imagination capturing the essence of a story far better than Super-superlative graphics, but I think that debate has been mirrored before with regards to Books vs. Movies. The main problem with your review is that you don’t really take into account how the internet has changed gaming. I used to have an easier time finding live gaming groups (D&D, Traveler, Star Fleet Battles, Axis and Allies, etc.) in the 80s than today’s which are almost always online. While I played a lot of single player games (Rogue – known today as NetHack, 3Demon, Kings Quest, Ultima, Empire I and II, etc.) I was more satisfied in sharing a story or adventure with other players. Today I find I play a lot of Multiplayer games, from RTS’s such as Company of Heroes, FPS such as Call of Duty 4/5 and BF2, to MMORPGs such as City of Heroes and EVE Online. But there has to be kept in mind that certain games are more geared towards Single Player vs. Multiplayer. BF2 and City of Heroes have absolutely no Single player aspect. But both vary deeply with regards to purpose: one is a multiplayer war sim while the other is a multiplayer RPG with story lines.
In my opinion many of the best single player RPGs can be best found coming out of Bioware’s house. I greatly enjoyed Neverwinter Nights, but found I played player created worlds far more than the single player game which certainly was not lacking for to-dos and side quests. The player mods carried NWN for years up until WoW hit. Bioware appears to be seeing the ‘singleplayer/multiplayer MMO light’ and will be jumping into producing MMORPGs with the new Star Wars MMO they are working on. Given their previous releases and experience with KotOR, it will certainly be no Star Wars Galaxies. Sure, you pay $$.$$ a month, but the support, expansions, depth, content, and player base promise to be worth it.
Single player games can be pretty fun without a strong story line: Descent II and III (though III was far better with regards to Multiplayer offerings than the story line). Freespace I and II were great story driven games, but again, like Descent revolved around flying, twitch combat, and a do or don’t continue story line. Privateer was certainly a favorite of mine (sorry to say I never played Elite) and Privateer II suffered a serious bug that was not fixed (if it ever was) before I lost the discs but looked like it had some potential as a sequel.
I am afraid that a lot of time spent making a game ‘deep’ and ‘complex’ with regards to AI, story morphing, and quests/missions is going to be absent from many current offline Single Player games due to Corporations looking at what will give the best return (much like the Music Industry – why do you think so many ‘artists’ sound like so many other from the Big Labels?) and given the oddities of the market place and the need for an ROI, who can blame them from hesitating on the new, fresh, different, and otherwise potential loss of money they face if they don’t go with what appears to be popular? Then there is the fear of piracy costing the loss of sales which again drives developers and publishers away from riskier titles to moving to subscription based formats where you ‘pay to play’. I think you will find less and less investment in story lines in non-pay to play gaming and more and more pay to play games presenting the story lines you seek. It is the logical direction for gaming developers who want to make a living in the profession to take who write stories vs. those who design the great next Shooter or Hack n’ Slash.
Imagine if Fallout 3 were and MMORPG?
P.S. – if I make little sense, I blame an inner ear infection that is making me woozy.
The games I have enjoyed most had a great sense of humour. Malcolm's revenge was lots of fun with the laugh track and snappy one liners... "what are all these idiots doing here". Monkey island had that scene where the parents appear as skeletons and start singing "the arm bone is connected to the ... bone". What a laugh. I'm not opposed to death in games, in grim vandango you are dead from the start but the game still has a nice warmth about it.
The Wii isn't "just waving a plastic remote around". If it was, I wouldn't play it.
Sure, there are a lot of cheapo games for the Wii. But there are some that held my attention for a long time. Bully on the Wii is the best version because of the great motion controls, and it took me over 30 hours to "finish" (finish the main storyline, that is; I never really tried at the minigames). You can't make moral decisions in Bully, but it's a great storyline and there's a lot of humour. Lots of side quests too.
Mario Kart Wii. At first glance, this looks like a kiddy racing game that uses a dumb gimmick. But despite having Mario Kart Wii for six months I'm still playing it; the online play is always thrilling and nail-biting, and masses of fun. Just do us a favour and use the classic controller as it's the best way to play. With a game like this, you don't need storyline; it's just fun. And isn't that what gaming is about?
Serious games, or games with full immersion are not beyond the Wii. When done correctly, motion controls enhance the immersion of the gameplay and allow for more control over the action - take a look at PES (Pro Evolution Soccer) on the Wii and see the level of control that the Wii remote and nunchuck allows players.
If they give you too much content in one game, you would not buy another.
I think that high graphics standards are knocking smaller vendors out of business. If the game is able to present great visuals, there must be people, a lot of them, who will design those visuals. That raises development costs. Bigger players have less competition, so they can afford themselves to screw the buyers.
Thom Holwerda - Really? You picked the Xbox360 over the PS3 and Wii? What a shock. You are an absolute brown noser to Microsoft so of course you would pick that instead of the better system. One clue, it's not the 360. Try to drop a little of your bias in your articles. It would also be nice if you posted your bio about how tied up with Microsoft you are. | http://www.osnews.com/comments/20679 | CC-MAIN-2017-51 | refinedweb | 11,885 | 70.13 |
I work with the
scipy.optimize.minimize
w,z
f(w,z)
w
z
[[1,1,1,1],
[2,2,2,2]]
def f(x):
w = x[0]
z = x[1]
...
minimize(f, [w,z])
scipy.optimize.minimize
Optimize needs a 1D vector to optimize. You are on the right track. You need to flatten your argument to
minimize and then in
f, start with
x = np.reshape(x, (2, m, n)) then pull out
w and
z and you should be in business.
I've run into this issue before. For example, optimizing parts of vectors in multiple different classes at the same time. I typically wind up with a function that maps things to a 1D vector and then another function that pulls the data back out into the objects so I can evaluate the cost function. As in:
def toVector(w, z): assert w.shape == (2, 4) assert z.shape == (2, 4) return np.hstack([w.flatten(), z.flatten()]) def toWZ(vec): assert vec.shape == (2*2*4,) return vec[:2*4].reshape(2,4), vec[2*4:].reshape(2,4) def doOptimization(f_of_w_z, w0, z0): def f(x): w, z = toWZ(x) return f_of_w_z(w, z) result = minimize(f, toVec(w0, z0)) # Different optimize functions return their # vector result differently. In this case it's result.x: result.x = toWZ(result.x) return result | https://codedump.io/share/itfzRIZoQzpZ/1/how-do-i-put-2-matrix-into-scipyoptimizeminimize | CC-MAIN-2017-34 | refinedweb | 228 | 70.09 |
Hi folks,
I see the java version is mentioned that functions auto close, but does this happen in the c# version?
I am having an issue as follows:
All my program should do is simply create the File object, like:
org.pdfclown.files.File mainFile = new org.pdfclown.files.File(fileName)
Then sometimes there is a corrupt pdf in my list of files, and Itry to catch the exception and move that file to a "bad pdf folder".
The problem is that when I go to move the file, I am getting an IOException saying that the file is already used by another process.
I have used many combinations of "using", and disposing of everything, etc. but I simply cannot seem to get org.pdfclown.files.File to release the file without completely exiting the program.
Catching the ParseException of org.pdfclown does work, I can increment my bad file count and move on to the next files in the folder - but later when I go to my routine to move the bad files, I cannot get the file unlocked.
Any advice please?
Thanks kindly!
Trev
Hi Trevor,
I know this is an older post but it still deserves an answer.
the C# version does not auto close files so you have to use mainFile.Dispose() before using System.IO.File to manipulate the file, this will force the file to be closed and you can then do with it as you wish.
Stefano Chizzolini
4 days ago
Hi Equalizer,
what do you mean with "the C# version does not auto close files"? AFAIK, as org.pdfclown.files.File implements IDisposable, its Dispose() method should get automatically called after exiting the
using block; your suggestion to explicitly invoke it makes sense in case the user needs its disposal before exiting such block -- don't you agree?
PS: I spotted the lack of finalizer in org.pdfclown.files.File, but apparently this shouldn't affect the case of Trevor -- fixed through IDisposable implementation refinement commit on 0.1.2-Fix branch (rev 141) and 0.2.0 trunk (rev 142). | http://sourceforge.net/p/clown/discussion/607162/thread/365f1fa0/ | CC-MAIN-2015-11 | refinedweb | 349 | 65.12 |
We are defining a couple of schema files that both contains element (digital signature) that refers to the w3c digital signature schema. The two schema files have different target namespace, and we'd like to put them in separate java packages too. When using default binding rules, duplicate class files appear in both packages. If I want the digital signature files in its own package, and let element in the two schema files refer to this package, how can I use custom bindings to achieve this? Thanks.
Frank
© 2016, O’Reilly Media, Inc.
(707) 827-7019
(800) 889-8969
All trademarks and registered trademarks appearing on oreilly.com are the property of their respective owners. | http://archive.oreilly.com/cs/user/view/cs_msg/40188?page=last&x-maxdepth=0 | CC-MAIN-2016-36 | refinedweb | 115 | 64 |
import "google.golang.org/appengine/aetest".
doc.go instance.go instance_vm.go user.go
PrepareDevAppserver is a hook which, if set, will be called before the dev_appserver.py is started, each time it is started. If aetest.NewContext is invoked from the goapp test tool, this hook is unnecessary.
Login causes the provided Request to act as though issued by the given user.
Logout causes the provided Request to act as though issued by a logged-out user.
NewContext starts an instance of the development API server, and returns a context that will route all API calls to that server, as well as a closure that must be called when the Context is no longer required.
type Instance interface { // Close kills the child api_server.py process, releasing its resources. io.Closer // NewRequest returns an *http.Request associated with this instance. NewRequest(method, urlStr string, body io.Reader) (*http.Request, error) }
Instance represents a running instance of the development API Server.
NewInstance launches a running instance of api_server.py which can be used for multiple test Contexts that delegate all App Engine API calls to that instance. If opts is nil the default values are used. // SupportDatastoreEmulator is whether use Cloud Datastore Emulator or // use old SQLite based Datastore backend or use default settings. SupportDatastoreEmulator *bool // SuppressDevAppServerLog is whether the dev_appserver running in tests // should output logs. SuppressDevAppServerLog bool // StartupTimeout is a duration to wait for instance startup. // By default, 15 seconds. StartupTimeout time.Duration }
Options is used to specify options when creating an Instance.
Package aetest imports 19 packages (graph) and is imported by 11 packages. Updated 2019-08-29. Refresh now. Tools for package owners. | https://godoc.org/google.golang.org/appengine/aetest | CC-MAIN-2019-39 | refinedweb | 276 | 51.24 |
5.8. Scope and Access¶
The scope of a variable is defined as where a variable is accessible or can be used. The scope is determined by where you declare the variable when you write your programs. When you declare a variable, look for the closest enclosing curly brackets { } – this is its scope.
Java has 3 levels of scope that correspond to different types of variables:
Class Level Scope for instance variables inside a class.
Method Level Scope for local variables (including parameter variables) inside a method.
Block Level Scope for loop variables and other local variables defined inside of blocks of code with { }.
The image below shows these 3 levels of scope.
public class Name { private String first; public String last; public Name(String theFirst, String theLast) { String firstName = theFirst; first = firstName; last = theLast; } }
public class Name { private String first; public String last; public Name(String theFirst, String theLast) { String firstName = theFirst; first = firstName; last = theLast; } }
Local variables are variables that are declared inside a method, usually at the top of the method. These variables can only be used within the method and do not exist outside of the method. Parameter variables are also considered local variables that only exist for that method. It’s good practice to keep any variables that are used by just one method as local variables in that method.
Instance variables at class scope are shared by all the methods in the class and can be marked as public or private with respect to their access outside of the class. They have Class scope regardless of whether they are public or private.
Another way to look at scope is that a variable’s scope is where it lives and exists. You cannot use the variable in code outside of its scope. The variable does not exist outside of its scope.
Try the following code to see that you cannot access the variables outside of their scope levels in the toString() method. Explain to someone sitting next to you why you can’t access these. Try to fix the errors by either using variables that are in scope or moving the variable declarations so that the variables have larger scope.
If there is a local variable with the same name as an instance variable, the variable name will refer to the local variable instead of the instance variable, as seen below. We’ll see in the next lesson, that we can distinguish between the local variable and the instance variable using the keyword this to refer to this object’s instance variables.
5.8.1.
Programming Challenge : Debugging¶
Debug the following program that has scope violations. Then, add comments that label the variable declarations as class, method, or block scope.
5.8.2. Summary¶
Scope is defined as where a variable is accessible or can be used.
Local variables can be declared in the body of constructors and methods. These variables may only be used within the constructor or method and cannot be declared to be public or private.
When there is a local variable with the same name as an instance variable, the variable name will refer to the local variable instead of the instance variable.
Formal parameters and variables declared in a method or constructor can only be used within that method or constructor.
5.8.3. AP Practice¶
- The class is missing an accessor method.
- There is a scope violation.
- The instance variables boxesOfFood and numOfPeople should be designated public instead of private.
- There is a scope violation. Instance variables are usually private.
- The return type for the Party constructor is missing.
- There is a scope violation. Constructors do not have return types.
- The variable updatedAmountOfFood is not defined in eatFoodBoxes method.
- There is a scope violation. The updatedAmountOfFood variable is a local variable in another method.
- The Party class is missing a constructor
- There is a scope violation.
5-8-3: Consider the following class definitions. Which of the following best explains why the class will not compile?
public class Party { private int boxesOfFood; private int numOfPeople; public Party(int people, int foodBoxes) { numOfPeople = people; boxesOfFood = foodBoxes; } public void orderMoreFood(int additionalFoodBoxes) { int updatedAmountOfFood = boxesOfFood + additionalFoodBoxes; boxesOfFood = updatedAmountOfFood; } public void eatFoodBoxes(int eatenBoxes) { boxesOfFood = updatedAmountOfFood - eatenBoxes; } }
The private variables currentPrice and movieRating are not properly initialized.
The constructor will initialize them.
The private variables currentPrice and movieRating should have been declared public.
Instance variables should be private.
The printPrice method should have been declared as private.
Methods are usually public.
currentPrice is declared as a local variable in the getCurrentPrice method and set to 16, and will be used instead of the instance variable currentPrice.
Correct!
The currentPrice instance variable does not have a value.
Accessor methods are usually public.
5-8-4: Consider the following class definition.
public class Movie { private int currentPrice; private int movieRating; public Movie(int p, int r) { currentPrice = p; movieRating = r; } public int getCurrentPrice() { int currentPrice = 16; return currentPrice; } public void printPrice() { System.out.println(getCurrentPrice()); } }
Which of the following reasons explains why the printPrice method is “broken” and only ever prints out a value of 16? | https://runestone.academy/runestone/books/published/csawesome/Unit5-Writing-Classes/topic-5-8-scope-access.html | CC-MAIN-2020-05 | refinedweb | 852 | 55.95 |
>
I very recently downloaded the stable release for Unity (2018.3.5f1). I have a project that talks to a microcontroller over the serial port, and in the past have used System.IO.Ports with no issue. However, just trying to import the namespace System.IO.Ports gives me this error in the editor and I am unable to compile:
error CS0234: The type or namespace name 'Ports' does not exist in the namespace 'System.IO' (are you missing an assembly reference?)
As you can see below, my configuration settings are to use .NET 4.x and compatibility level is set to 2.0 (NOT subset, which isn't even available in the list):
If I set the "Scripting Runtime Version" to ".NET 3.5 Equivalent", the problem goes away. The only problem is that 3.5 is deprecated, and I would like to use something a little more future proof. Am I doing something wrong here? Do I need to check my .NET 4.x installation to see if it is missing some libraries? According to MSDN documentation, System.IO.Ports should be available in .NET 4.x. This problem persists across multiple machines & Unity installations of 2018.3.x. Any help greatly appreciated!!
Answer by xxmariofer
·
Feb 20 at 03:58 PM
Hello, you need to set api compatibility level to net 4.x(tested with 2018.3.0f2 version)
THANK YOU! I could have sworn I tried that but indeed, switching the compatibility level to 4.x fixes it! After lots of searching and many posts from older versions that weren't relevant for me, I finally have the solution. Thanks again!
Answer by soccer_guru
·
Mar 14 at 06:29 PM
I had the same problem, and I can confirm that you first need to switch to the deprecated .NET 3.5 Equivalent first, before switching to .NET 4.X and setting the API compatibility level. Switching the API Compatibility level first, weirdly, doesn't work.
i didnt understand your post, you cant set up the compatibility level before changing the scripting runtime version since the first one is dependant of the second one. you cant have .net 4x without 4.x runtime version
Hey @xxmariofer, I meant to say that switching to .net 4.x equivalent and setting the API compatibility level .net 4.x didn't work at once for me. It only worked after I switched to the .net 3.5 and then switched back to .net 4.x.
Answer by CVTunity
·
Apr 30 at 03:16 PM
I also had the same problem. I used scripting runtime version .net 4.x Equivalent and Api Compatibility Level .Net 4.x. But I needed to build the solution in the IDE after switching from .Net Standard 2.0.
Issues With Accessing Classes Nested In System.IO (Unity 2017.1.0f3)
0
Answers
HMAC Initialization throws and error. How to solve it
1
Answer
Gain access to directory
1
Answer
Hard crash when accessing certain members of SerialPort
1
Answer
error with system.io.ports
0
Answers | https://answers.unity.com/questions/1604233/systemioports-missing-for-unity-with-net-4x.html | CC-MAIN-2019-22 | refinedweb | 511 | 69.89 |
Jaime Rodriguez On Windows Store apps, Windows Phone, HTML and XAML,
Happy Windows Phone coding!
I am writing this tiny demo app, that has a TextBox data bound to a ViewModel. I want the TextBox to fire notifications to the ViewModel whenever the text changes (as opposed to only firing notifications when the textbox loses focus). In WPF, this is trivial to do, you just set the UpdateSourceTrigger on the Binding to PropertyChanged (in fact, I think that is the default). On the phone, I only see UpdateSourceTrigger supporting:
What to do? [12/5 (Update part 1) -- Updating this post due to enough feedback that the semantic of TextChanged is better than my post’s KeyUp. I did try that before suggesting KeyUp on my original post but I was seeing TextChanged fire more often than KeyUp (aka more times than I felt necessary). Now that I have seen there is no big perf hit (since others are doing it with TextChanged) I am back to proper semantics. Also you made me second guess and I tested on a keyboard and noticed that arrows can even the score firing KeyUp events.
How about:
Here are the snippets: In my XAML,
1: <TextBox x:Name="empIdTextBox" Text="{Binding Id, Mode=TwoWay, UpdateSourceTrigger=Explicit}"
2:
1: private void empIdTextBox_TextChanged(object sender, TextChangedEventArgs e)
2: {
3: TextBox box = (TextBox)sender;
4: BindingExpression be = box.GetBindingExpression(TextBox.TextProperty);
5: be.UpdateSource();
6:
7: }
1: public class UpdateSourceOnTextChangedBehavior : Behavior<TextBox>
2: {
3:
4: protected override void OnAttached()
5: {
6: base.OnAttached();
7: this.AssociatedObject.TextChanged += this.OnTextChanged;
8: }
9:
10: private void OnTextChanged(object sender, TextChangedEventArgs e)
11: {
12: BindingExpression be =
13: this.AssociatedObject.GetBindingExpression(TextBox.TextProperty);
14: be.UpdateSource();
15: }
16:
17: protected override void OnDetaching()
18: {
19: base.OnDetaching();
20: this.AssociatedObject.TextChanged -= this.OnTextChanged;
21: }
22: }
1: <TextBox x:Name="empIdTextBox" Grid.Column="1"
2:
3: <interactivity:Interaction.Behaviors>
4: <local:UpdateSourceOnTextChangedBehavior />
5: </interactivity:Interaction.Behaviors>
6: </TextBox>
Yesterday I did a dry-run of my performance talk for today’s Silverlight fire starter.
Conclusion was that the talk is like drinking from a fire-hose. It is tight for 45 minutes, but the content is good and we could not agree on what to cut. It was all too good and useful to cut stuff.
So, I am going to cheat and give you an early preview and a guide to make it easy to follow along.
Join me today at 4:30 PST. Live at Silverlight fire starter. if you can’t make it, check later for final document, including a part 2 and the video recording. | http://blogs.msdn.com/b/jaimer/archive/2010/12.aspx?PostSortBy=MostRecent&PageIndex=1 | CC-MAIN-2015-48 | refinedweb | 437 | 57.16 |
22 February 2010 17:20 [Source: ICIS news]
LONDON (ICIS news)--European methyl di-p-phenylene isocyanate (MDI) buyers are bemused by Bayer Material Science's (BMS) decision to restart its idled MDI facility at Brunsbuettel, Germany, amid ongoing poor demand in the construction sector and an oversupply situation, sources said on Monday.
A BMS source confirmed that its MDI Brunsbuettel unit came back online in mid-February and was producing again.
The seller declined to comment about precise operating rates or the reasons for the start-up. The Brunsbuettel MDI plant was idled on 1 April 2009 until further notice due to a lack of demand amid the poor economic climate.
Buyers and some resellers questioned the timing of the start-up: “The restart is a bit early due to the ongoing poor weather and market conditions,” said one MDI source.
Another buyer noted: “It was quite a courageous move. Maybe they anticipate that demand will come back, as there is the approaching spring season. However, there is already too much MDI in the market before the restart. Demand is still poor and there are no signs of improvement yet.”
A trader said: “The start-up is a big mistake, it is very strange. Demand is still poor. Everyday, suppliers are trying to push volumes,” which was echoed by a consumer, who stated: “The MDI market is as long as I have ever seen it.”
The source estimated that construction activity, one of the main outlets for crude MDI, was down by approximately 50% in the ?xml:namespace>
The customer added that it also expected a drop-off in the automotive sector, another outlet for MDI, following the end of the various government incentive programmes.
Buyers also anticipated that the BMS restart “would put pay to any targeted price increases”.
BASF, and most recently Dow, announced plans to raise prices by €200/tonne ($274/tonne) due to unsustainable price levels, driven by the uptrend in feedstock costs and the price erosion for MDI.
Sellers’ reactions were mixed. One producer considered the Bayer MDI restart to be good news, noting: “They are seeing the light at the end of the tunnel. They are seeing the crisis abating a bit.”
A few weeks ago, another manufacturer said it had no immediate plans to bring back online its mothballed MDI unit in the first half of 2010. The source had said it did not want to jeopardise the market balance. No further update on the status of this facility was available.
Regarding the proposed hikes of up to €200/tonne for MDI over the next few months, some sellers maintained a firm stance. One producer stressed that increases were vital due to the need for re-investment economics, alongside the benzene feedstock cost pressure.
Crude MDI prices were assessed in February between €1,470-1,510/tonne FD (free delivered) NWE (northwest
The BMS plant at | http://www.icis.com/Articles/2010/02/22/9336781/bayers-brunsbuettel-mdi-restart-amid-poor-market-surprises-buyers.html | CC-MAIN-2014-41 | refinedweb | 484 | 61.06 |
Fire to integrate Firestore with Ionic to create a CRUD work-flow. This sample app will show you how to:
- Showing a list of items from your database (which in Firestore is called displaying a collection of documents).
- Creating a new item and adding it to the list.
- Navigating to that item’s detail page.
- Deleting an item from our list.
We will break down this process in X steps:
- Step #1: Create and Initialize our Ionic app.
- Step #2: Add items to the list.
- Step #3: Show the list of items.
- Step #4: Navigate to one item’s detail page.
- Step #5: Delete an item from the list.
Now that we know what we’re going to do let’s jump into coding mode.
Step #1: Create and Initialize your app
The goal of this step is to create your new Ionic app, install the packages we’ll need (only Firebase and AngularFire2), and initialize our Firebase application.
With that in mind, let’s create our app first, open your terminal and navigate to the folder you use for coding (or anywhere you want, for me, that’s the Development folder) and create your app:
cd Development/ ionic start firestore-example blank cd firestore-example
After we create the app we’ll need to install Firebase, for that, open your terminal again and (while located at the projects root) type:
npm install angularfire2 firebase
That command will install the latest stable versions of both AngularFire2 and the Firebase Web SDK.
Now that we installed everything let’s connect Ionic to our Firebase app.
The first thing we need is to get our app’s credentials, log into your Firebase Console and navigate to your Firebase app (or create a new one if you don’t have the app yet).
In the Project Overview tab you’ll see the ‘Get Started’ screen with options to add Firebase to different kind of apps, select “Add Firebase to your web app.”
Out of all the code that appears in that pop-up window focus on this bit:
var config = { apiKey: "Your credentials here", authDomain: "Your credentials here", databaseURL: "Your credentials here", projectId: "Your credentials here", storageBucket: "Your credentials here", messagingSenderId: "Your credentials here", };
That’s your Firebase config object, it has all the information you need to access the different Firebase APIs, and we’ll need that to connect our Ionic app to our Firebase app.
Go into your
src/app folder and create a file called
credentials.ts the idea of this file is to keep all of our credentials in one place, this file shouldn’t be in source control so add it to your
.gitignore file.
Copy your config object to that page. I’m going to change the name to something that makes more sense to me:
export var firebasConfig = { apiKey: "AIzaSyBJT6tfre8uh3LGBm5CTiO5DUZ4", authDomain: "javebratt-playground.firebaseapp.com", databaseURL: "", projectId: "javebratt-playground", storageBucket: "javebratt-playground.appspot.com", messagingSenderId: "3676553551" };
We’re exporting it so that we can import it into other files where we need to.
Now it’s time for the final piece of this step, we need to initialize Firebase, for that, let’s go into
app.module.ts and first, let’s import the AngularFire2 packages we’ll need and our credential object:
import { AngularFireModule } from 'angularfire2'; import { AngularFirestoreModule } from 'angularfire2/firestore'; import { firebaseConfig } from './credentials';
Since we’re only going to use the Firestore database, we import the base AF2 (I’m going to refer to AngularFire2 as AF2 from now on) module and the Firestore module. If you also needed Authentication or Storage you’d need to add those modules here.
Inside your
@NgModule() look for your
imports array and add both the AF2 module and the Firestore module:
imports: [ BrowserModule, IonicModule.forRoot(MyApp), AngularFireModule.initializeApp(firebaseConfig), AngularFirestoreModule, ],
We’re calling the
.initializeApp(firebaseConfig) method and passing our credential object so that our app knows how to connect to Firebase.
And that’s it, it might not look like much yet, but our Firebase and Ionic apps can now talk to each other.
Step #2: Add items to the list.
It’s time to start working with our data, we’re going to build a CRUD app, we’ll use a song list as an example, but the same principles apply to any Master/Detail work-flow you want to build.
The first thing we need is to understand how our data is stored, Firestore is a document-oriented NoSQL database, which is a bit different from the RTDB (Real-time Database.)
It means that we have two types of data in our database, documents, which are objects we can work with, and collections which are the containers that group those objects.
For example, if we’re building a song database, our collection would be called songs, or songList, which would hold all the individual song objects, and each object would have its properties, like the song’s name, artist, etc.
In our example, the song object will have five properties, an id, the album, the artist, a description, and the song’s name. In the spirit of taking advantage of TypeScript’s type-checking features, we’re going to create an interface that works as a model for all of our songs.
Go into the
src folder and create a folder called
models, then add a file called
song.interface.ts and populate it with the following data:
export interface Song { id: string; albumName: string; artistName: string; songDescription: string; sonName: string; }
That’s the song’s interface, and it will make sure that whenever we’re working with a song object, it has all the data it needs to have.
To start creating new songs and adding them to our list we need to have a page that holds a form to input the song’s data, let’s create that page with the Ionic CLI, open the terminal and type:
ionic generate page Create
In fact, while we’re at it, let’s take a moment to create the detail page, it will be a detail view for a specific song, and the Firestore provider, it will handle all of the database interactions so that we can manage everything from that file.
ionic generate page Detail ionic generate provider Firestore
Now we need a way to go from the home page to the CreatePage, for that open
home.html and change your header to look like this:
<ion-header> <ion-navbar <ion-title> Song List </ion-title> <ion-buttons end> <button ion-button icon-only (click)="goToCreatePage()"> <ion-icon</ion-icon> </button> </ion-buttons> </ion-navbar> </ion-header>
We’re adding a button to the header that triggers the
goToCreatePage() function, to make that work, let’s open the
home.ts file and write that function:
import { Component } from '@angular/core'; import { NavController } from 'ionic-angular'; @Component({ selector: 'page-home', templateUrl: 'home.html', }) export class HomePage { constructor(public navCtrl: NavController) {} goToCreatePage(): void { this.navCtrl.push('CreatePage'); } }
The only thing that function is doing is taking you to the
CreatePage, now that we can get to that page it’s time to build its functionality. The functionality will consist of 3 things:
- The HTML view that shows the form.
- The TypeScript Class that collects the form data and sends it to the provider.
- The function in the provider that creates the song and adds it to the list of songs.
Let’s start with the HTML, open the
create.html file and inside the
<ion-content></ion-content> tags create the form:
<ion-content> <form [formGroup]="createSongForm" (submit)="createSong()" novalidate> <ion-item> <ion-label stacked>Song Name</ion-label> <ion-input </ion-input> </ion-item> <ion-item> <ion-label stacked>Artist Name</ion-label> <ion-input </ion-input> </ion-item> <ion-item> <ion-label stacked>Album Name</ion-label> <ion-input </ion-input> </ion-item> <ion-item> <ion-label stacked>Song Description</ion-label> <ion-textarea </ion-textarea> </ion-item> <button ion-button block Add Song </button> </form> </ion-content>
If you’re new to angular forms then here’s what’s going on:
[formGroup]="createSongForm"=> This is the name of the form we’re creating.
(submit)="createSong()"=> This tells the form that on submit it should call the
createSong()function.
formControlName=> This is the name of the field.
[disabled]="!createSongForm.valid"=> This sets the button to be disabled until the form is valid.
Now let’s move to the
create.ts file, in here, we’ll collect the data from our form and pass it to our provider. First, let’s import everything we’ll need:
import { Component } from '@angular/core'; import { IonicPage, NavController, Loading, LoadingController, AlertController, Alert, } from 'ionic-angular'; import { FormGroup, FormBuilder, Validators } from '@angular/forms'; import { FirestoreProvider } from '../../providers/firestore/firestore';
We’re importing:
- Form helper methods from
@angular/forms.
- Loading controller to show a loading widget to our users while the form processes the data.
- Alert controller to display an alert to our user if there are any errors.
- And the Firestore provider to call the function that will add the song to the database.
Now we need to inject all those providers to the constructor and initialize our form:
public createSongForm: FormGroup; // This is the form we're creating. constructor( public navCtrl: NavController, public loadingCtrl: LoadingController, public alertCtrl: AlertController, public firestoreProvider: FirestoreProvider, formBuilder: FormBuilder ) { this.createSongForm = formBuilder.group({ albumName: ['', Validators.required], artistName: ['', Validators.required], songDescription: ['', Validators.required], songName: ['', Validators.required], }); }
And now all we need is the function that collects the data and sends it to the provider if you remember the HTML part, we called it
createSong()
createSong(): void { }
The first thing we want to do inside that function is to trigger a loading component that will let the user know that the data is processing, and after that, we’ll extract all the field data from the form.; }
And lastly, we’ll send the data to the provider, once the song is successfully created the user should navigate back to the previous page, and if there’s anything wrong while creating it we should display an alert with the error message.; this.firestoreProvider .createSong(albumName, artistName, songDescription, songName) .then( () => { loading.dismiss().then(() => { this.navCtrl.pop(); }); }, error => { loading.dismiss().then(() => { const alert: Alert = this.alertCtrl.create({ message: error.message, buttons: [{ text: 'Ok', role: 'cancel' }], }); alert.present(); }); } ); }
NOTE: As a good practice, handle those errors yourself, instead of showing the default error message to the users make sure you do something more user-friendly and use your custom messages, we’re technicians, we know what the error means, most of the time our users won’t.
We almost finish this part, all we need now is to create the function inside the provider that receives all the form data we’re sending and uses it to create a song in our database.
Open
providers/firestore/firestore.ts and let’s do a few things, we need to:
- Import Firestore.
- Import our Song interface.
- Inject firestore in the constructor.
- And write the
createSong()function that takes all the parameters we sent from our form.> { } }
The function is taking all of the parameters we’re sending. Now we’re going to do something that might seem unusual. We’re going to use the firestore
createId() function to generate an id for our new song.(); } }
Firestore auto-generates IDs for us when we push items to a list, but I like to create the ID first and then store it inside the item, that way if I pull an item I can get its ID right there, and don’t have to do any other operations to get it.
Now that we created the id, we’re going to create a reference to that song and set all the properties we have, including the id.(); return this.firestore.doc(`songList/${id}`).set({ id, albumName, artistName, songDescription, songName, }); } }
That last piece of code is creating a reference to the document identified with that ID inside our
songList collection, and after it creates the reference, it adds all the information we sent as parameters.
And that’s it. You can now add songs to our list. And once each song is created the user will navigate back to the homepage, where we’ll now show the list of songs stored in the database.
Step #3: Show the list of items.
To show the list of songs we’ll follow the same approach we used for our last functionality, we’ll create the HTML view, the TypeScript Class, and the function inside the provider that communicates with Firebase.
Since we have the provider opened from the previous functionality let’s start there, we want to create a function called
getSongList() the function should return a collection of songs:
getSongList(): AngularFirestoreCollection<Song> { return this.firestore.collection(`songList`); }
Note that for that to work you need to import
AngularFirestoreCollection from the
angularfire2/firestore package (Or remove the type checking if you don’t care about it).
Now, let’s go to the home page and import everything we’ll need:
import { Song } from '../../models/song.interface'; import { FirestoreProvider } from '../../providers/firestore/firestore'; import { Observable } from 'rxjs/Observable';
We want the
Song interface for a strict type checking, the
FirestoreProvider to communicate with the database, and
Observable also for type checking, our provider will return an AngularFirestoreCollection that we’ll turn into an observable to display on our view.
Then, inside our class we want to create the
songList property, we’ll use it to display the songs in the HTML, and inject the firestore provider in the constructor.
public songList: Observable<Song[]>; constructor( public navCtrl: NavController, public firestoreProvider: FirestoreProvider ) {}
And lastly we want to wait until the page loads and fetch the list from our provider:
ionViewDidLoad() { this.songList = this.firestoreProvider.getSongList().valueChanges(); }
The
.valueChanges() method takes the AngularFirestoreCollection and transforms it into an Observable of type Songs.
Now we can go to
home.html and inside the
<ion-content> we’ll loop over our list of songs to display all the songs in the database.
<ion-content> <ion-card * <ion-card-header> {{ song.songName }} </ion-card-header> <ion-card-content> Artist Name: {{ song.artistName }} </ion-card-content> </ion-card> </ion-content>
We’re only showing the song’s name and artist’s name, and we’re adding a click event to our card, once the user clicks the card, it should trigger the
goToDetailPage() function and pass the entire song object as a parameter.
We haven’t created that function so let’s take a moment to create it on our homepage:
goToDetailPage(song: Song): void { this.navCtrl.push('DetailPage', { song: song }); }
The function navigates the user to the Detail page and passes the entire song object as a navigation parameter, on the next section we’ll use that navigation parameter to display the whole song’s data in the detail page.
For now, grab a cookie or something, you’ve read a lot, and you’re sugar levels might need a boost. See you in a few minutes in the next section 🙂
Step #4: Navigate to one item’s detail page.
In the previous step, we created a function that takes us to the detail page with the song information, and now we’re going to use that information and display it for the user to see.
Instead of talking to the provider to fetch the song record, we’re passing the entire song as a navigation parameter, so we don’t need to import our firestore provider right now.
The first thing we’ll do is go to
detail.html and create a basic view that displays all the data we have for our song:
<ion-header> <ion-navbar <ion-title> {{ song.songName }} </ion-title> </ion-navbar> </ion-header> <ion-content padding> <h3> Artist </h3> <p> The song {{ song.songName }} was released by {{ song.artistName }}. </p> <h3> Album </h3> <p> It was part of the {{ song.albumName }} album. </p> <h3> Description </h3> <p> {{ song.songDescription }} </p> </ion-content>
We’re showing the song’s name in the navigation bar, and then we’re adding the rest of the data to the content of the page.
Now let’s jump into
detail.ts so we can get
song otherwise this will error out.
All you need to do is create a property
song of type
Song, for that we need to import the
Song interface.
Then, you want to get the navigation parameter we sent to the page and assign its value to the
song property you created.
import { Component } from '@angular/core'; import { IonicPage, NavController, NavParams } from 'ionic-angular'; import { Song } from '../../models/song.interface'; @IonicPage() @Component({ selector: 'page-detail', templateUrl: 'detail.html', }) export class DetailPage { public song: Song; constructor(public navCtrl: NavController, public navParams: NavParams) { this.song = this.navParams.get('song'); } }
You should do a test right now running
ionic serve your app should be working, and you should be able to create new songs, show the song list, and enter a song’s detail page.
Step #5: Delete an item from the list.
In the last part of the tutorial we’re going to add a button inside the DetailPage, that button will give the user the ability to remove songs from the list.
First, open
detail.html and create the button, nothing too fancy, a regular button that calls the remove function will do, set it right before the closing ion content tag.
<button ion-button block (click)="deleteSong(song.id, song.songName)"> DELETE SONG </button> </ion-content>
Now go to the
detail.ts and create the
deleteSong() function, it should take 2 parameters, the song’s ID and the song’s name:
deleteSong(songId: string, songName: string): void {}
The function should trigger an alert that asks the user for confirmation, and if the user accepts the confirmation, it should call the delete function from the provider, and then return to the previous page (Our home page or list page).
deleteSong(songId: string, songName: string): void { const alert: Alert = this.alertCtrl.create({ message: `Are you sure you want to delete ${songName} from your list?`, buttons: [ { text: 'Cancel', handler: () => { console.log('Clicked Cancel'); }, }, { text: 'OK', handler: () => { this.firestoreProvider.deleteSong(songId).then(() => { this.navCtrl.pop(); }); }, }, ], }); alert.present(); }
NOTE: Make sure to import Alert, AlertController, and our FirestoreProvider for this to work.
Now, all we need to do is go to our provider and create the delete function:
deleteSong(songId: string): Promise<void> { return this.firestore.doc(`songList/${songId}`).delete(); }
The function takes the song ID as a parameter and then uses it to create a reference to that specific document in the database. Lastly, it calls the
.delete() method on that document.
And that’s it. You should have a fully functional Master/Detail functionality where you can list objects, create new objects, and delete objects from the database 🙂
Next Steps
Congratulations, that was a long one, but I’m confident you now understand more about Firestore and how to use it with Firebase.
If you’d like to learn more about Firestore and start building more complete Ionic applications I created a Crash Course that covers the theory behind what we saw here, it also includes Cloud Functions triggers for Firestore and Firestore Security Rules.
YOU CAN GET IT FOR FREE HERE. | https://javebratt.com/crud-ionic-firestore/ | CC-MAIN-2018-26 | refinedweb | 3,212 | 59.74 |
Program hangs with NLO thW production
Asked by Stefan von Buddenbrock on 2018-02-05
Dear MadGraph authors
We have been trying to generate pp > thW at NLO with the following:
import model loop_sm-no_b_mass
define p = 21 2 4 1 3 -2 -4 -1 -3 5 -5
define j = p
define tt = t t~
define wpm = w+ w-
generate p p > h wpm tt [QCD]
When I try run the event generation, it compiles quickly and passes all checks. However, the integration step gets stuck and never makes any progress... I tried this on 2.6.0, but I think the problem also happens on 2.5.5 and 2.6.1.
Is this kind of computation possible in aMC@NLO? It seems strange to me, since th production is relatively simple and adding another W shouldn't impact the QCD corrections too much.
Cheers
Stefan
Question information
- Language:
- English Edit question
- Status:
- Solved
- Assignee:
- marco zaro Edit question
- Solved by:
- Stefan von Buddenbrock
- Solved:
- 2018-02-06
- Last query:
- 2018-02-06
- Last reply:
- 2018-02-05
Hi Marco
Thanks, the link you sent is what I need.
Cheers
Stefan
Hi Stefan,
the problem with tWh is that some resonant diagrams with a top quark appear. It has been detailed in this paper
arXiv:1607.05862
however, the part of the code where the contribution of the resonant top quark is subtracted has not been made public yet...
What do you need to do exactly?
cheers,
marco | https://answers.launchpad.net/mg5amcnlo/+question/664097 | CC-MAIN-2018-17 | refinedweb | 249 | 68.91 |
XML JSON Data Format (camel-xmljson)
Available as of Camel 2.10
Camel already supports a number of data formats to perform XML and JSON-related conversions, but all of them require a POJO either as an input (for marshalling) or produce a POJO as output (for unmarshalling). This data format provides the capability to convert from XML to JSON and viceversa directly, without stepping through intermediate POJOs.
This data format leverages the Json-lib library to achieve direct conversion. In this context, XML is considered the high-level format, while JSON is the low-level format. Hence, the marshal/unmarshal semantics are assigned as follows:
- marshalling => converting from XML to JSON
- unmarshalling => converting from JSON to XML.
Options
This data format supports the following options. You can set them via all DSLs. The defaults marked with (*) are determined by json-lib, rather than the code of the data format itself. They are reflected here for convenience so that you don't have to dot back and forth with the json-lib docs.
Basic Usage with Java DSL
Explicitly instantiating the data format
Just instantiate the XmlJsonDataFormat from package org.apache.camel.dataformat.xmljson. Make sure you have installed the
camel-xmljson feature (if running on OSGi) or that you've included camel-xmljson-{version}.jar and its transitive dependencies in your classpath. Example initialization with a default configuration:
To tune the behaviour of the data format as per the options above, use the appropriate setters:
Once you've instantiated the data format, the next step is to actually use the it from within the
marshal() and
unmarshal() DSL elements:
Defining the data format in-line
Alternatively, you can define the data format inline by using the
xmljson() DSL element.
If you wish, you can even pass in a Map<String, String> to the inline methods to provide custom options:
Basic usage with Spring or Blueprint DSL
Within the
<dataFormats> block, simply configure an
xmljson element with unique IDs:
Then you simply refer to the data format object within your
<marshal /> and {<unmarshal />}} DSLs:
Enabling XML DSL autocompletion for this component is easy: just refer to the appropriate Schema locations, depending on whether you're using Spring or Blueprint DSL. Remember that this data format is available from Camel 2.10 onwards, so only schemas from that version onwards will include these new XML elements and attributes.
The syntax with Blueprint is identical to that of the Spring DSL. Just ensure the correct namespaces and schemaLocations are in use.
Namespace mappings
XML has namespaces to fully qualify elements and attributes; JSON doesn't. You need to take this into account when performing XML-JSON conversions.
To bridge the gap, Json-lib has an option to bind namespace declarations in the form of prefixes and namespace URIs to XML output elements while unmarshalling (i.e. converting from JSON to XML). For example, provided the following JSON string:
you can ask Json-lib to output namespace declarations on elements "pref1:a" and "pref2:b" to bind the prefixes "pref1" and "pref2" to specific namespace URIs.
To use this feature, simply create
XmlJsonDataFormat.NamespacesPerElementMapping objects and add them to the
namespaceMappings option (which is a
List).
The
XmlJsonDataFormat.NamespacesPerElementMapping holds an element name and a Map of [prefix => namespace URI]. To facilitate mapping multiple prefixes and namespace URIs, the
NamespacesPerElementMapping(String element, String pipeSeparatedMappings) constructor takes a String-based pipe-separated sequence of [prefix, namespaceURI] pairs in the following way:
|ns2|.
In order to define a default namespace, just leave the corresponding key field empty:
|ns1|.
Binding namespace declarations to an element name = empty string will attach those namespaces to the root element.
The full code would look like that:
And you can achieve the same in Spring DSL.
Example
Using the namespace bindings in the Java snippet above on the following JSON string:
Would yield the following XML:
Remember that the JSON spec defines a JSON object as follows:
An object is an unordered set of name/value pairs. [...].
That's why the elements are in a different order in the output XML.
Dependencies
To use the XmlJson dataformat in your camel routes you need to add the following dependency to your pom. | https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=27845564&showComments=true&showCommentArea=true | CC-MAIN-2015-11 | refinedweb | 701 | 51.68 |
In this chapter, we’re going to explore JavaScript programming styles and how developers worked with types in JavaScript (rather than JS++). This chapter will help you understand the next chapters which explain the JS++ type system in detail.
In this tutorial, we will be using the Google Chrome web browser. Click here to download Google Chrome if you don’t already have it.
In order to execute JavaScript code, we’ll be using the Chrome Developer Tools console. Open Chrome and hit the Ctrl + Shift + J key combination and choose the “Console” tab.
Copy and paste the following code into your console and press enter to execute it:
var message; message = "This is a test."; if (Math.random() > 0.5) { message = 123; } console.log(message);
Hit your “up arrow” and hit “enter” to evaluate the code more than once. Try evaluating the code a few times.
Notice how the data type in the above code changes from a string to a number. However, it only changes to a number if a randomly-generated number is greater than 0.5. Therefore, the data type of the variable ‘message’ can be different each time the script is executed. This was a major problem in JavaScript. For example, the following JavaScript code is unsafe:
function lowercaseCompare(a, b) { return a.toLowerCase() == b.toLowerCase(); }
The reason is because toLowerCase() is a method that’s only available to JavaScript strings. Let’s execute the following JavaScript code in the Chrome console:
function lowercaseCompare(a, b) { return a.toLowerCase() == b.toLowerCase(); } console.log("First message."); lowercaseCompare("10", 10); // Crashes with 'TypeError' console.log("Second message."); // Never executes.
Notice how the script will crash with a TypeError. The second message never gets logged. The key takeaway is that the code crashed because toLowerCase() is not a method available for numbers, but the function was called with a string (“10”) and a number (10). The number argument was not a valid argument for the ‘lowercaseCompare’ function. If you change the function call, you will observe that the program no longer crashes:
// Change this: // lowercaseCompare("10", 10); // Crashes with 'TypeError' // to: lowercaseCompare("10", "10");
Developers worked around these problems in JavaScript by checking the types first. This is the safer way to rewrite the above ‘lowercaseCompare’ function in JavaScript:
function lowercaseCompare(a, b) { if (typeof a != "string" || typeof b != "string") { return false; } return a.toLowerCase() == b.toLowerCase(); }
We check the types using ‘typeof’, and, if we receive invalid argument types, we return a default value. However, for larger programs, this can result in a lot of extra code and there may not always be an applicable default value.
Unforgiving Errors in JavaScript
In the previous example, we explored one type of unforgiving error in JavaScript: a TypeError that causes script execution to end. There are many other types of errors that JS++ prevents, but, for now, we’ll only look at one other category of errors: ReferenceErrors. What’s wrong with the next bit of JavaScript code?
var message = "This is a test."; console.log(messag);
Try executing the above code in your console. Once again, nothing gets logged. Instead, you get a ReferenceError. This is because there’s a typo in the above code. If we fix the typo, the code succeeds:
var message = "This is a test."; console.log(message);
JavaScript can fail on typos! TypeErrors and ReferenceErrors don’t happen in JS++. We classify TypeErrors and ReferenceErrors as “unforgiving” errors because they can cause JavaScript script execution to halt. However, there’s another type of error in JavaScript that’s a little more dangerous because they’re “silent.”
Forgiving “Silent” Errors in JavaScript
There is a class of “silent” errors in JavaScript that can silently continue to propagate through your program. We call these “forgiving” errors because they don’t stop script execution, but, despite the innocuous name, we can consider them more dangerous than unforgiving errors because they continue to propagate.
Consider the following JavaScript function:
function subtract(a, b) { return a - b; }
This function might seem straightforward on the surface, but – as the script gets more complex – when variables change and depend on other values spanning thousands of lines of code, you might end up accidentally subtracting a variable that ends up being a number from a variable that ends up being a string. If you attempt such a call, you will get NaN (Not a Number).
Evaluate the following code in your console:
function subtract(a, b) { return a - b; } subtract("a", 1);
Observe the resulting NaN (Not a Number) value. It doesn’t crash your application so we call it a forgiving error, but the error value will propagate throughout the rest of your program so your program continues to silently run with errors. For example, subsequent calculations might depend on the value returned from the ‘subtract’ function. Let’s try additional arithmetic operations to observe:
function subtract(a, b) { return a - b; } var result = subtract("a", 1); // NaN console.log(result); result += 10; // Add 10 to NaN console.log(result);
No crash and no error reports. It just silently continues to run with the error value.
You won’t be able to run the following code, but here’s an illustration of how such error values might propagate through your application in a potential real-world scenario, a shopping cart backend:
var total = 0; total += totalCartItems(); while ((removedPrice = removedFromCart()) != null) { total = subtract(total, removedPrice); } total += tax(); total += shipping();
In the example above, our shopping cart can end up with a NaN (Not a Number) value – resulting in lost sales for the business that can be difficult to detect because there were no explicit errors.
JavaScript Intuition
JS++ was designed based on extensive JavaScript development experience – not just for large, complex applications but anywhere JavaScript could be used – scripts and macros for Windows Script Host to legacy programs based on ActiveX and the like which are still prevalent in some corporate environments. In short, JS++ will work anywhere that JavaScript is expected – from the basic to the complex to the arcane.
One important observation relevant to JS++ is that most JavaScript programs are already well-typed (but not “perfectly” typed). Recall the “unsafe” and “safe” versions of the JavaScript ‘lowercaseCompare’ function:
// Unsafe: function lowercaseCompare(a, b) { return a.toLowerCase() == b.toLowerCase(); } // Safe: function lowercaseCompare(a, b) { if (typeof a != "string" || typeof b != "string") { return false; } return a.toLowerCase() == b.toLowerCase(); }
The safe version is much more tedious, and – in practice – most JavaScript developers will write most of their functions the unsafe way. The reason is because, by looking at the function body, we know the expected parameter types are strings because both parameters use the ‘toLowerCase’ method only available to strings. In other words, in JavaScript, we have an intuition about the types just by looking at the code.
Consider the following variables and guess their types:
var employeeAge; var employeeName; var isEmployed;
employeeAge makes sense as a number, employeeName makes sense as a string, and isEmployed makes sense as a Boolean.
Now try guessing the expected parameter types for the following functions:
function multiply(a, b) { return a * b; } function log(message) { console.log("MESSAGE: " + message); }
The function ‘multiply’ makes most sense if you supply numeric arguments to the ‘a’ and ‘b’ parameters. Furthermore, the ‘log’ function is most correct with strings.
JavaScript Forced Conversions (“Type Coercion”)
Sometimes, instead of checking the type using ‘typeof’, JavaScript programmers will instead force a conversion of the argument to the data type they need (especially if intuition might fail). This technique is an instance of type coercion and results in code that is more fault tolerant because it won’t exit with an exception if the data type of the argument provided is incorrect.
Once again, let’s see how we can change our ‘lowercaseCompare’ example using this idea:
// Unsafe: function lowercaseCompare(a, b) { return a.toLowerCase() == b.toLowerCase(); } // Safer: function lowercaseCompare(a, b) { a = a.toString(); b = b.toString(); return a.toLowerCase() == b.toLowerCase(); }
In the re-written version of the ‘lowercaseCompare’ function, we are “forcing” the ‘a’ and ‘b’ arguments to be converted to a string. This allows us to safely call the ‘toLowerCase’ method without a crash. Now, if the ‘lowercaseCompare’ function is called, we get the following results:
lowercaseCompare("abc", "abc") // true lowercaseCompare("abc", 10) // false lowercaseCompare("10", "10") // true lowercaseCompare("10", 10) // true
However, the astute observer will notice the new version of ‘lowercaseCompare’ is marked “safer” rather than “safe.”
Why?
toString is not the most correct way to force a conversion to a string. (It’s also not the fastest due to runtime method lookups, but imagine having to consider all these details while writing one line of code? This is how programming for the web used to be before JS++.)
One example is if we try to call ‘lowercaseCompare’ with a variable we forgot to initialize, it will crash again if we use ‘toString’. Let’s try it:
function lowercaseCompare(a, b) { a = a.toString(); b = b.toString(); return a.toLowerCase() == b.toLowerCase(); } var a, b; // uninitialized variables var result = lowercaseCompare(a, b); console.log(result); // Never executes
No, instead, the most correct way to perform type coercion to string would be like this:
// Finally safe: function lowercaseCompare(a, b) { a += ""; // correct type coercion b += ""; // correct type coercion return a.toLowerCase() == b.toLowerCase(); } var a, b; var result = lowercaseCompare(a, b); console.log(result);
There’s just one problem left with the correct code: it becomes unreadable. What would your code look like if you had to insert += “” everywhere that you wish to express the intent that you want string data?
‘lowercaseCompare’ in JS++
Now that was a lot to digest! Writing good code in JavaScript is hard. Imagine having to take into account all these considerations when writing a small bit of code in JavaScript: safety, performance, code readability, unforgiving errors, silent errors, correctness, and more. This actually only scratches the surface of JavaScript corner cases, but it provides us enough information to begin understanding types in JS++.
However, if we write our code in JS++, JS++ actually handles all these considerations for us. This means you can write code that is readable, but the JS++ compiler will handle generating code that is fast, safe, and correct.
Before we move on to the next chapter – which explains the JS++ type system in detail – let’s try to rewrite the ‘lowercaseCompare’ code in JS++. We’ll start with code that is intentionally incorrect to show you how JS++ catches such errors early and show you how to fix them. Create a ‘test.jspp’ file and type in the following code:
import System; function lowercaseCompare(string a, string b) { return a.toLowerCase() == b.toLowerCase(); } Console.log("First message."); lowercaseCompare("10", 10); Console.log("Second message.");
Try compiling the file. It won’t work. JS++ found the error early:
[ ERROR ] JSPPE5024: No overload for `lowercaseCompare' matching signature `lowercaseCompare(string, int)' at line 8 char 0 at test.jspp
It tells you exactly the line where the error occurred so you can fix it – before your users, visitors, or customers get a chance to encounter it. Let’s fix the offending line, which JS++ told us was on Line 8:
// lowercaseCompare("10", 10); // becomes: lowercaseCompare("10", "10");
Run the code after fixing the offending line. In Windows, right-click the file and choose “Execute with JS++”. In Mac or Linux, run the following command in your terminal:
js++ --execute test.jspp
You’ll see both messages logged successfully.
In the next chapter, we’ll explore the JS++ type system and “type guarantees” by example.
Recommended Posts:
- JS++ | Variables and Data Types
- JS++ | Classes, OOP, and User-defined Types
- JS++ | Static Members and "Application-Global" Data
- JS++ | The 'final' Modifier
- JS++ | Interfaces
- JS++ | Event Handlers
- JS++ | Abstract Classes and Methods
- JS++ | Access Modifiers and 'super'
- JS++ | Subtype Polymorphism
- JS++ | Virtual Methods
- JS++ | Static vs. Dynamic Polymorphism
- JS++ | Upcasting and Downcasting
- JS++ | Inheritance
- JS++ |. | https://www.geeksforgeeks.org/js-types-in-javascript/ | CC-MAIN-2018-51 | refinedweb | 1,993 | 54.32 |
Sometimes you would get a data sheet as CSV file which needs to import in SQL, the problem is CSV files don’t really care what data type in the sheet, unlike SQL.
Let’s say you have a books CSV file, and one of the columns in it is publication year, in SQL you would store it as an Integer. And all good you just cast fields in this column as integer and store it, the problem is that you also reading the header of the spreadsheet and it a string which can’t be converted to an integer. In this case, you would just start to insert data into your table from the second row. Here is how to do it:
import csv f = open("books.csv") reader = csv.reader(f) # to skip the header row, othervise it would through an error when try to cast string into integer for the years next(reader) | https://93days.me/ignore-csv-header-in-python/ | CC-MAIN-2021-39 | refinedweb | 156 | 75.44 |
This page describes the mechanics of how to contribute software to Apache Avro. For ideas about what you might contribute, please look in Avro's JIRA database.
Getting the source code
First of all, you need the Avro source code.
The easiest way is to clone or fork the GitHub mirror:
git clone -o github
Making Changes
Before you start, file an issue in JIRA or discuss your ideas on the Avro developer mailing list. Languages
- Contributions should pass existing unit tests.
- Contributions should document public facing APIs.
- Contributions should add new tests to demonstrate bug fixes or test new features.
Java
- All public classes and methods should have informative Javadoc comments.
- Do not use @author tags.
- Code should be formatted according to Sun's conventions, with one exception:
- Indent two spaces per level, not four.
- JUnit is our test framework:
- You must implement a class whose class name starts with
Test.
- Define methods within your class and tag them with the @Test annotation. Call JUnit's many assert methods to verify conditions; these methods will be executed when you run
mvn test.
- By default, do not let tests write any temporary files to
/tmp. Instead, the tests should write to the location specified by the
test.dirsystem property.
- Place your class in the
src/test/java/tree.
- You can run all the unit tests with the command
mvn test, or you can run a specific unit test with the command
mvn -Dtest=<class name, fully qualified or short name> test(for example
mvn -Dtest=TestFoo test)
Unit Tests
Please make sure that all unit tests succeed before constructing your patch and that no new compiler warnings are introduced by your patch. Each language has its own directory and test process.
Java
> cd avro-trunk/lang/java > mvn clean test
Python
> cd avro-trunk/lang/py > ant clean test
Python3
> cd avro-trunk/lang/py3 > ./setup.py build test
C
> cd avro-trunk/lang/c > ./build.sh clean > ./build.sh test
C++
> cd avro-trunk/lang/c++ > ./build.sh clean test
Ruby
> cd avro-trunk/lang/ruby > gem install echoe > rake clean test
PHP
> cd avro-trunk/lang/php > ./build.sh clean > ./build.sh test
Documentation
Please also check the documentation.
Java
> mvn compile > mvn javadoc:aggregate > firefox target/site/apidocs/index.html
Examine all public classes you've changed to see that documentation is complete, informative, and properly formatted. Your patch must not generate any javadoc warnings.
Contributing your code
You can create a pull request or attach a patch file to the JIRA issue you're working on. Please note that the attachment should be granted license to ASF for inclusion in ASF works (as per the Apache License).
Check to see what files you have modified with:
git status
Add any new or changed files with:
git add src/.../MyNewClass.java git add src/.../TestMyNewClass.java
Finally, create a commit with your changes and a good log message:
git commit -m "AVRO-1234: Fix NPE by adding check to ..."
Creating a patch
In order to create a patch, type:
git diff > AVRO-1234.patch
This will report all modifications done on Avro sources on your local disk and save them into the
AVRO.htmlfiles, this wiki, etc.)
- name the patch file after the JIRA –
AVRO-<JIRA#>.patch
Applying a patch
To apply a patch either you generated or found from JIRA, you can issue
patch -p0 < AVRO-<JIRA#>.patch
if you just want to check whether the patch applies you can run patch with
--dry-run option
patch -p0 --dry-run < AVRO-<JIRA#>.patch
If you are an Eclipse user, you can apply a patch by:
- Right click project name in Package Explorer
- Team -> Apply Patch
Finally, patches should be ''attached'' to an issue report in JIRA via the '''Attach File''' link on the issue's Jira. Please add a comment that asks for a code review following our code review checklist.
Contributing your patch
When you believe that your patch is ready to be committed, select the '''Submit Patch''' link on the issue's Jira.
Folks should run tests before selecting '''Submit Patch'''. Tests should all pass. Javadoc should report '''no''' warnings or errors. AVRO-#.patch where AVRO-# or check out their pull request. first line of the git commit message.
Changes are normally committed to master first, then, if they're backward-compatible, cherry-picked to a branch.
When you commit a change, resolve the issue in Jira. When resolving, always set the fix version and assign the issue. Set the fix version to either to the next minor release if the change is compatible and will be merged to that branch, or to the next major release if the change is incompatible and will only be committed to trunk. Assign the issue to the primary author of the patch. If the author is not in the list of project contributors, edit their Jira roles and make them an Avro contributor.
Jira Guidelines Avro mailing lists. In particular, the commit list (to see changes as they are made), the dev list (to join discussions of changes) and the user list (to help others). | https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=21791803 | CC-MAIN-2018-09 | refinedweb | 858 | 64.81 |
Default value of a field?
This not a bug. Just don't understand how to deal it.
Question
When user not assign a value to a special field. I want the special field be assigned a default value. for example:
- user input:
apple==
apple type:fruit
- user input:
apple type:red==
apple type:red
I think it maybe need to write a simply qparser.Plugin but I still don't know how to do it.
Can you give me a example? Or any help?
Very thanks!
My Search Code
import whoosh.qparser as WQ import whoosh.highlight as WH def index_search(query_string): """Get search results from user's input""" ix = WI.open_dir(INDEX_DIR) with ix.searcher() as searcher: # Configure a QueryParser qp = WQ.QueryParser("text", INDEX_SCHEMA) # Add two plugins qp.add_plugin(WQ.MultifieldPlugin(["text", "pname", "pdesc"])) qp.add_plugin(DateParserPlugin()) # generate query by user's input query = qp.parse(query_string) # real searching... results = searcher.search(query, limit = 20, terms=True) results.fragmenter = WH.PinpointFragmenter(autotrim = True) return generate_html_from_template("data-search.html", results = results)
Ooh, good question. It's complicated because if you're using the default query parser you can have arbitrary query trees like
However, if you're OK with saying that if the query has any term in the "type" field then you'll turn off the "default", then the simplest way is probably to just inspect and modify the parsed query:
Wow! You are right... It more complex than I thought before.
I will reconsider implement or not.
And thanks your nice example! (^_^)/ | https://bitbucket.org/mchaput/whoosh/issues/381/default-value-of-a-field | CC-MAIN-2015-48 | refinedweb | 256 | 62.95 |
Bug Description
Binary package hint: emacs21-common
here is a comp.lang.python thread I started with the exact same text I'm reporting here for this bug. There's some good discussion from people who really know python on there:
http://
I've been using pdb under emacs on an Ubuntu box to debug python programs. I just upgraded from Ubuntu Edgy to Feisty and this combo has stopped working. Python is at 2.5.1 now, and emacs is at 21.41.1.
It used to be I could just "M-x pdb RET pdb <script-name> RET" and be presented with a prompt where I could debug my script, as well as an
arrow in another source code buffer indicating where I am in the source code.
Now however, when I do "M-x pdb RET pdb ~/grabbers/
Current directory is /home/levander/
No prompt or anything follows it, just that one line. It doesn't pop up an arrow in the other buffer either. None of the regular commands
like 'n', 's', or 'l' do anything here. So, I did a 'Ctrl-C' and got:
> /home/levander/
-> """
(Pdb) > /home/levander/
-> import getopt
(Pdb) Traceback (most recent call last):
File "/usr/bin/pdb", line 1213, in main
pdb.
File "/usr/bin/pdb", line 1138, in _runscript
self.
File "bdb.py", line 366, in run
exec cmd in globals, locals
File "<string>", line 1, in <module>
File "/home/
import getopt
File "/home/
import getopt
File "bdb.py", line 48, in trace_dispatch
return self.dispatch_
File "bdb.py", line 66, in dispatch_line
self.
File "/usr/bin/pdb", line 144, in user_line
self.
File "/usr/bin/pdb", line 187, in interaction
self.cmdloop()
File "cmd.py", line 130, in cmdloop
line = raw_input(
KeyboardInterrupt
Uncaught exception. Entering post mortem debugging
Running 'cont' or 'step' will restart the program
> /home/levander/
-> pass
(Pdb)
It's wierd because at the bottom of that call stack, it does look like it's wating for input, but no input works... And, after I hit Ctrl-C I do get a prompt as you see at the bottom of that listing just above. Now I type "quit" and get:
Post mortem debugger finished. The /home/levander/
grabber.py will be restarted
I tried pdb in the emacs-snapshot and emacs-snapshot-gtk packages. It doesn't work in those places either.
However, Alexandre Vassalotti is maintaining an emacs package because he wants custom fonts or something like that. pdb is working for me with his package. Instructions for installing his package can be found on his blog in this entry:
http://
I haven't tried ipython.el that can be downloaded from the internet with anything but the Ubuntu emacs21 package. I plan to try it with Alexandre's package soon.
Things continue like this...
at least emasc-snapshot works correctly
I just tried this the other day on Gutsy. pdb mode worked fine for me. I was using the emacs package, not emacs-snapshot.
Is this still an issue for you? Which Ubuntu version do you use? Thank you for telling us!
[Expired for emacs21 (Ubuntu) because there has been no activity for 60 days.]
Just wanted to add that this bug really shocks me. Aren't there a lot of Canonical developers using python? Do they just not use emacs or pdb to debug their code?
That Usenet thread I pointed to has stuff about ipython.el that you can download from other places on the internet not working also. | https://bugs.launchpad.net/ubuntu/+source/emacs21/+bug/114933 | CC-MAIN-2015-40 | refinedweb | 586 | 76.01 |
I have been trying to install Scipy onto my Python 3.5 (32-bit) install on my Windows 7 machine using the pre-built binaries from:
I have, in order, installed the following libraries
numpy‑1.10.1+mkl‑cp35‑none‑win32.whl
scipy‑0.16.1‑cp35‑none‑win32.whl
from scipy import sparse
< ... Complete error trace ommitted ... >
packages\scipy\sparse\csr.py", line 13, in <module>
from ._sparsetools import csr_tocsc, csr_tobsr, csr_count_blocks, \
ImportError: DLL load failed: The specified module could not be found.
numpy‑1.10.1+mkl‑cp35‑none‑win32.whl
scipy‑0.16.1‑cp35‑none‑win32.whl
Make sure you pay attention to this line from the link you provided:
Many binaries depend on NumPy-1.9+MKL and the Microsoft Visual C++ 2008 (x64, x86, and SP1 for CPython 2.6 and 2.7), Visual C++ 2010 (x64, x86, for CPython 3.3 and 3.4), or the Visual C++ 2015 (x64 and x86 for CPython 3.5) redistributable packages.
Download the corresponding Microsoft Visual C++ Redistributable Package which should be this one based on your description.
I had a similar problem, can't recall the exact issue, and I download the one for my system and it worked fine. Let me know otherwise. | https://codedump.io/share/cC7IRaxbtlBv/1/installing-scipy-in-python-35-on-32-bit-windows-7-machine | CC-MAIN-2017-30 | refinedweb | 210 | 69.48 |
in reply to Re^2: Top Level Module Namespace Tablein thread Top Level Module Namespace Table
Amazing how difficult it is for me to express myself precisely on this issue! I thought an example would be explicit. Sorry. Please allow me to attempt to improve.
I'm well acquainted with CPAN Search; it's a great tool. I'm not sure how much an ordinary dev will want to use Parse::CPAN::Modlist; but that's cool. Both of these are solutions to the problem of I want to download a module that does This. They are statements of what is. This is a common problem and an important one; but it's not the issue I'm attempting to address.
The table I seek is not descriptive but prescriptive. This is where the markers for deprecated namespaces come in.* This table goes no further than the top level of namespaces, perhaps some well-defined second levels (e.g., CGI::Application::). It's a statement of what should be.
Reviewing the descriptions of existing modules is indeed a way to infer prescriptions for future efforts, I admit. By the same token, one course of bricks is a guide to placing the next. Yet, if we want a wall to stand neatly, we generally use a plumb line.
I realize that I touch upon philosophical issues here.** My feeling is only that I will be more comfortable writing modules -- even modules that may never escape from my own project -- that are named in conformance with some plan.
I'm coming rapidly to the belief that no such table exists (I'd like to be wrong!) and that creating it is a worthwhile project. I wrote the original node in hopes that Monks might suggest a good way to get it started.
*.
Hidden. | http://www.perlmonks.org/?node_id=821563 | CC-MAIN-2016-36 | refinedweb | 301 | 73.88 |
.
Now, I hope to see a lot of "C++ is bad, mmmkay" rants, but perhaps I can forestall a few of the more obvious points.
I used to take every opportunity to bash C++. I found the sheer complexity of the language appalling, I was put off by the way in which it builds a high-level language on the "portable assembler" of C, and I was enraged by the many terrible pitfalls and simple misfeatures present in the language (such as multiple inheritance and slicing). Instead, I thought the world should migrate to a "real" high-level language like ML, Haskell, or perhaps Sather. It didn't help that the C++ draft standard was constantly changing and that the compilers which were available were horribly incomplete and buggy, requiring you to discover by trial and error the set of "safe reduced C++" that wouldn't cause internal compiler errors or "sorry, not implemented".
Furthermore, I noticed an inverse correlation between C++ use and quality in free software. If I downloaded a free software package, and saw files named "*.cc", "*.cpp", "*.cxx", or "*.c++", it was a safe bet that the software wouldn't compile without my help, and that when I did get it running, it would be buggy, slow, bloated, incomplete, and overengineered ("just like the language!"). Of the free software I admired as "good" and was happy to use on a day-to-day basis, almost all of it was written in ordinary ANSI C.
I also saw plenty of examples of really bad C++ which used all the wrong features of the language, resulting in an ornate mess. I also saw plenty of "shell shocked" programmers who reacted to the problems above by circumscribing an incredibly narrow set of features ("C with classes") and thereby eliminating much of the benefit the language has to offer.
Why am I arguing in favor of C++ now, then? What's changed?
Well, the standard is finalized, and gcc in particular is very close to implementing the whole thing. It is now possible to use templates in all their glory (including templated members, partial specialization, and so on) without feeling like one is treading a rotten boardwalk. The full power of the STL is available (including extensions developed by Stepanov and friends at SGI).
I've also identified a subset of the C++ language that I like (I avoid inheritance from anything but an abstract base class, I try to stay away from iostreams, and I hardly ever overload operators, for example), and perhaps most importantly, I've given up hope that my beloved research languages will ever see widespread adoption (that's a completely different topic of discussion).
C++ is far from perfect (the binary linkage problem is a bummer, but maybe that's what CORBA is for), but it offers a combination of flexibility, performance, and compatibility that no other language shares. It certainly seems far cleaner to use a C++ abstract base class than to hack yet another set of C callbacks with "void*" casts, and I'll take list<> over glist any day.
Nevertheless, the free software developers of the world clearly disagree, and I'd like to find out (with as little flaming as possible) why.
I mean, let's just assume, for the sake of argument, that all the participants here are informed people with some taste differences. some like C, others like C++, yet others like neither.
what is the reason to discuss it yet again? there won't be any converts, you can quote me on this.
for now, i'm going to limit my comments to c++ and the gnu project. first, let me see something...$ lynx -dump -nolist | grep [cC]++
* adns is a resolver library for C and C++ programs. * Binutils includes these programs: `addr2line', `ar', `c++filt', * Cgicc is a C++ class library for writing CGI applications. * CommonC++ is a C++ framework offering portable support for * cpp2html s a simple program that, given a source C/C++ file, * GCC is a free compiler collection for C, C++, Fortran, Objective C * gdb is a source-level debugger for C, C++ and Fortran. small, self-contained C++ library of 3D Widgets that support * Goose is a C++ library for statistical calculations. * libxmi is a C/C++ function library for rasterizing 2-D vector * Mifluz provides a C++ library to build and query a full text C++. OBST supports incremental loading of methods. * The Plotutils package contains `libplot', a C/C++ library that can * ACS is an core class extensible C++ state engine and IVR * APE is a highly portable C++ framework for the development of * CLN is a C++ class library for numbers. It provides arbitrary * The Epeios project provides C++ libraries for multiple use. * Fltk is a LGPL'd C++ graphical user interface toolkit for X, * GiNaC is a framework of C++ classes to perform some symbolic * NURBS++ is a C++ library that hides the basic mathematics of
hmm, you're right -- not a lot of stuff.
three immediate thoughts come to mind: first, i have a vague recollection of an old version of the gnu coding standards recommending that programs be written in c rather than c++ because of c's greater mindshare at the time. second, it has taken g++ a long time to reach its current state of maturity. third, c++ did not become an iso standard until quite recently, especially compared to c, no? these would all be contributing factors, though obviously i'm not an official mouthpiece of the gnu project. also noteworthy, perhaps, is that neither richard stallman nor miguel de icaza programs in c++
Seriously. My current major project is a Jabber client for GNOME. Dave Smith, the developer of a general Jabber client library called jabberoo, which was written in C++ decided to start hacking on the code for the user interface I designed in glade. He decided on C++ because jabberoo was already in C++ and there are gtk and gnome bindings for C++, so it seemed logical. Unfortunately, now that the project is more mature, we're still having trouble getting Gabber working on many machines. The problem is the binary incompatibilities between g++ versions. Some people get binaries of libsigc++ and gtkmm from Helix GNOME compiled on gcc 2.95.2, but then gnomemm compiled on egcs 1.1.2. SEGFAULT. Any possible combination of one lib not being compiled on the proper compiler results in segfault. Just look at bugs.gnome.org, package gabber. We don't even use the GNOME bug system, so those are reports from people who just hit the 'submit bug report' button in GNOME after it segfaults. I'm pretty sure most of them are because of library incompatibilities. Until gcc 3.0 comes around, I can't imagine that many developers would put up with this. Supposedly this won't happen after 3.0, but we'll see.
Not only are there binary incompatibilities, but g++ is SLOW... Look at how loing it takes to compile Mozilla. Have you ever seen it compiled on a windows machine with a decent compiler? Much much faster. Until it's optimized, people will have a tough time rationalizing the incredible amounts of time it takes to compile for just a few nicer programming features. I know I do...
To sum it up, we need to get g++ fixed - and get the fixed version on most of the popular *nixes...
The article does a good job of explaining the laundry list of problems most folks have.
All the problems of "makes it easier for dumb programmers to write bad code," et al, are relatively minimal. Good programers can write good stuff with C++, like they even can with *shudder* Tcl. Folks will notice good programs, and then those programs will be used.
But "the standard has been finalized" means nothing. Nada. How long was it until C89 was supported everywhere? How long will it be until ANSI C++ is? That's the question.
g++ is not the answer. I know how good gcc is on some plaforms, and how bad it is on others. when g++ is ready on Linux/*BSD, that will only be the beginning. We cannot rely on g++ to suffice for other platforms, because not enough folks care to make g++ (or even gcc) work well there. I know that when I was using other Unices, I avoided C++ programs merely because of this problem.
So I, for one, will probably avoid C++ until ANSI C++ compilers are ubiquitous.
Another possible factor is the fact that with C, the interested, knowledgeable, and otherwise helpful group of folks that will help debug and patch your code is much larger.
I went through a similar process to what egnor describes, avoiding C++ for years, then suddenly waking up when the generic programming features became available that this was a (high level) language I'd actually want to use.
apgarcia already said this, but for me the issue was very much about maintaining the lowest possible barrier to entry. This must be changing with so many people learning C++ as part of their university degree, but in my generation C was the lowest common denominator. Largely because C++ is such a large language, using it for open development reduces the pool of people likely to contribute. In contrast, I always liked ObjectiveC because you could explain it to any C programmer in 20 minutes. Even Java is similarly intelligible.
It's also much easier to share code if you share languages. If you're writing in C++, you don't want to import crufty C code from some other project and end up doing more work reimplementing stuff. Likewise, I know I've personally avoided perfectly functional code because it was in C++ because I didn't want the hassle of wrapping/backporting it. I wonder if that has something to do with the popularity of GTK over QT or FLTK, or SDL over Clanlib (despite most games being in C++ these days).
Maybe there's a balkanization issue here as well. I'm much less threatened by high-level scripting languages, or experimental ones. But to the extent that C++ tries to "be a better C" it feels like a religious issue.
To add to the list, there are a couple of successful-ish open source projects using C++. Worldforge and CrystalSpace come to mind.
cmm: I ask because I'm curious. Despite the way the article is written, I'm not looking to change any minds, and I am willing to have my mind changed. Above all, I'm very interested in the reasons that make some languages be widely accepted in some communities while others (which are apparently technically superior, but perhaps not) languish. I'm also interested in the differences between free software and commercial development practices, and the impact of those differences on language choice (and vice versa). I would also like to "feel the wind" to see if it's likely that C++ will see more adoption in the future.
apgarcia: I can't tell if you're being sarcastic or not with your conclusion "you're right -- not a lot of stuff".
julian: I agree that binary portability is a problem, and I agree that gcc is somewhat slow to process C++ files (especially templates), but I'm not sure the statement that "it sucks" is fair. It's certainly not fair to talk about egcs 1.1.2, since that's quite old by now. Still, you may be answering my question; perhaps the big reasons nobody uses C++ are that it has been poorly supported until recently (if so, we should expect the situation to change) and that binary linking doesn't work (is there any hope that the "new ABI" will be stable?). Interesting.
jlbec: Does g++'s support for C++ features really vary from platform to platform? I'm surprised; I would have thought that for the most part, the C++ compiler implementation is at a "higher level" than most platform-specific details (with some exceptions, like, uh, exceptions, and thread-safety).
I also wonder how important portability is to free software developers. On the one hand, it's often cited here as a reason to avoid C++ and to support cross-platform solutions like GLib, but on the other hand many of the free software programs I use seem proudly POSIX- or perhaps even Linux-specific.
I'm not sure I buy the "inertia"/"developer mindshare" argument brought up by jlbec; that hasn't stopped anyone from adopting Perl, for example. But rillian makes the interesting claim that the barrier to entry is different for a "scripting language". Can you expand on that?
It's interesting that C++ seems to be adopted by game developers first (this happenned in the commercial world, and may be happenning here as well). I've been told that commercial game development leapt directly from assembler to C++. If free software game developers are adopting C++, then perhaps we can look there for the shape of things to come.
I can only agree with julian there: g++, even in 2.95.2, sucks. Badly. On the alpha, which I'm primarily working on, it generates incorrect code and broken virtual function tables. If I turn off code optimization. With optimization, it usually dies with an internal compiler error. Things may become better with the 2.95.3 interim release, but right now I'm stuck with Compaq's cxx. This compiler works, but doesn't like the Debian system header files, which use some g++ magic (e.g. to automagically map stuff into the std:: namespace). Also, it's proprietary and binary only.
Anyway, ignoring the compiler issue, there's another point why C++ isn't used that commonly among free software authors (and I'm not just talking about "compared to C" here): If absolute portability (and, therefore, C) or restricted portability (C++) and performance (either of them) aren't an issue for your project, those languages aren't neccessarily among the obvious choices. For example, for something related to text processing, you might use Perl. For a clean, functional OO program, Python would be an appropriate choice. If your program has to be robust and should handle unexpected choices, you might want to build a language of your own, or use reasoning languages like Mercury or Prolog. If you're working with mathematically inclined people, you might want to have a look at Haskell. Many of these offer features not present in either C or C++, thus decreasing the time spent in development.
(For example, a researcher I know wrote a theorem proving program in Prolog; it was exactly 333 bytes long and beat many of the worlds' professional theorem provers in benchmarks).
Of course, I'm not saying that C++ is obsolete, or shouldn't be used. I just wanted to point out that, in a free software world, your boss isn't forcing you to use C++ or Java because he read that it's a good language.
egnor: the reason I reacted so crankily (besides being very cranky lately, that is :) is that all these language discussions strike me as, well, stupid and useless fidgeting.
at work, most sub-senior level people are basically limited to what the boss chooses or what the organization uses. we might as well deal with it, pretty much.
for hobbies/crusades/learning, other considerations come, thankfully, into the picture. but then, you don't really care whether the language you choose is the most popular. all you care about is a vibrant community. and there are plenty of such languages. lessee: Python, ML, Haskell, Prolog, Scheme, Lisp, etc etc. don't worry your heads about which of these languages has the longest d^W^W^W^W is the most popular. just use the one you like.
Most successful C++ programmers I know had extensive background in C programming and a functional object-oriented programming language like CLOS/LOOPS/Flavors (LISP variants) or Smalltalk before picking up C++. Nowadays I think it would be programmers who are experienced in both C and Java or C and Python who would be ready to try C++.
On top of that, you need an XP-like mentality to be able to deal with the evolution of large object-oriented applications, which was something not found in any textbook until recently.
Err, how about
Curiously, no one has mentioned the granddaddy of free software c++ apps, Mozilla. The also nicely provided us with the c++ portability guide. And they seem to be a current succes (they can handle this diary entry). And no one has mentioned KDE.
But as I don't know anything about Mozilla, other than that it works, I'll talk about AbiWord, a Free software C++ application that works quite nicely. We use basically two kinds of C++ features:
For the first kind, I really don't see why anyone really wants to use free and malloc more than they absolutely have to. I'm sure glad I don't.For the first kind, I really don't see why anyone really wants to use free and malloc more than they absolutely have to. I'm sure glad I don't.
- Better C features
- Classes and inheritance
For the second kind, C++ make our lives much much easier. AbiWord is designed from the ground up to be an XP GUI app, which isn't easy. The way we do this is to have base classes in the XP code, and then the actually implemented classes as derived classes in the platform-specific code. This allows everyone to share code cleanly and nicely, and people doing platform specific work to stay out of each other's hair.
As for C++ not being portable, all I can say is that we are about to ship a binary release for 7 operating systems on 4 different architechtures. Granted, we don't use advanced C++ features. But we probably could.
Of those people who hate C++ currently, how many of you have actually worked on a serious C++ project?
I think most "free software" projects don't start with a clean slate design. They are much more of a "stone soup" kind of thing, you almost always start with something that's close to what you want and hack on it until it does want you need. You do this a bunch of times and build up a set of internal mental programming tools. When you do get a chance ( or make a chance ) to work from scratch, you grab from your already built set of design tools.
So until there is a significant amount of C++ to hack on, there won't be lots of C++ hacking.
Personally, I've tried to give C++ a serious look a few times and decided not to bother until there is a rich stable set of underlying class libraries. OO is generally useless until there is a broad underlying STABLE[1] set of class objects. That and the lack of run-time binding ( has this been fixed?) made it seem not worth my time.
- Booker C. Bense
[1]- I define STABLE to mean that I can still compile the same code five years down the road.
One reason for the preference to C over C++ may be that libraries may be written in C more often than C++ because of a desire to cater to as wide an audience as possible. If I write a library in C++ it will only be really usable in other C++ programs, partly due to the C++ name mangling and partly to the use of OO features. If, however, I write my library in C, then it can be used in both C and C++ programs with equal utility without any extra effort. If I'm feeling really nice I might write a set of wrapper classes in C++, but it just makes more sense to put the real meat of the code in pure ISO C.
If more libraries are written in C than in C++, the result will be more programs written in C than in C++ because it is easier to write the programs in a language with more support in libraries. If more programs are written in C than in C++ then you will have a greater impetus to write future libraries in the more commonly used language. It looks like something of a catch-22.
Persoanally, I don't like C++ for the same reasons mentioned by egnor (baroque language design, assorted misfeatures, non-portable compiler features, etc.) and just find it much easier to concieve programs in simpler languages (e.g. C or Java). When I worte my library of standard utilities I used C rather than C++, even though the library has some object-like features, because I knew that I would need to use the library in both C and C++ programs.
Aside from the already mentioned problems of no good C++ compiler existing and it being relatively useless to write a library in C++ since that lowers the number of prospective users...
How about the hypothesis that a larger portion of the opensource hackers out there prefer languages where its relatively obvious what's going on underneath (ie: low level languages like C) or just don't bother with such an "arcane" concept as a machine-code-compiled languages that can do such evil things as segfault and not run on more than one platform so they pick modern languages (python, perl, etc..)?
just a thought.
I've never met any c++ programmer that I found impressive. I'm sure they do exist, but, they are pretty rare too. Most of the c++ code I've seen was trying to use the c++ features, which made it unreadable (for me non-c++-litterate programmer) and bloated. I would end up rewriting it in straight c and make it twice faster in the process. So much for the "it does not hurt the performance" - maybe when you're really really good at c++, but, most people arent.
I know I'm not good at c++. Most of the code that I write (codecs, compression/decompression stuff, engines for whatever) has to be efficient. When I write them I have to think about what the compiled code will look like, and c++ just makes it hard for me. Also whats the deal with templates - when I write the code I know what types it will have to play with, and I dont remember having to switch them afterwards. I may have to use a hash table or something at times, but, its not like I will take days to write one, and in the process I'll adapt the implementation to what I actually need. For example, if I'm hashing strings you can bet I will use a more complex hash function than if I'm hashing pgp key IDs that are already pretty uniformly distributed... I think the c++ genericity argument falls on his face here again, because, all hash tables do not have the same requirements.
So, I don't think c++ would be a huge advantage for the stuff that I do, and I think I would need to invest a massive amount of time to become maybe half-decent at it. It just does not seem to be worth it IMHO.
When I dont want to worry about the lowlevel implementation, I'd rather use python or another "proper" high-level language. But, c++ just looks like a bad hack to me.
C++ and free software have nothing in conflict. Unix and C++ don't really mix as well as Unix and C since Unix and C were developed and designed with one another.
And the GNU C++ compiler which is the most popular on free opertaing systems happens to suck...
I'm not sure what all the fuss is about. The Exult project is written in C++, has nearly 69K lines of code, and compiles/runs on Linux, Win32, Mac and BeOS. G++ is used for all platforms except for the Mac, and I haven't heard of any problems caused by the compiler.
In my opinion, C++ is a natural choice for a game, since a game is full of objects:-) And, in fact, it appears that the original Ultima7 (which Exult reverse-engineers) was itself written using Borland C++.
bbense: I think you are definitely right about the chicken and egg problem. Most FS C++ projects (such as AbiWord, Mozilla, or KDE) were written from scratch. However, your claim that OO is useless without a large set of class libraries (a la Java) is untrue. The abstraction benifits of OO are available, even without such a library, in addition to other benifits of C++.
dutky: Again, it does seem reasonable to write libraries in C, when they will be used by coders working in multiple languages. However, there is no reason not to use C++ for your application, if your library is written in C. The C interface can be used identically in either C or C++. Granted, it is often nicer to have a C++ wrapper around the library, but this is by no means a requirement.
walken: You just haven't seen enough C++ code. I assure you there are pople with beautiful coding skills out there. The AbiWord piecetable implementation, for example, hasn't been changed in 20 months. And we haven't found a bug in it yet. The author of that code has retired to enjoy the fruits of his labors, and deservedly too.
As for you comments about templates, they are totally clueless. First, a template bears no relation whatsoever to a hash table. Sure, you could have a hash table implemented as a template, but there's no intrinsic connection. Furthermorethe idea of templates is to be able to use them with any time, even types that you didn't think of (or hadn't even been created). An vector library that uses arrays can be linked to a app using it, even if the datatypes put in the array were invented years after the lib was compiled. Let's see you do that with a hash table.
samth: Actually, if you look carefully, I did in fact mention both Mozilla and KDE in the article. I consider them "exceptions that prove the rule" because both started from proprietary efforts (Netscape, Qt), and we all know that C++ is quite popular among proprietary software developers.
aaronl: I think we should cut GNU C++ a little bit of slack. Lots of people are happy to say "g++ sucks". It's true, there are some problems: C++ support on non-Intel platforms is broken, compilation is slow, and C++ lacks binary compatibility between compiler versions. Still, try using, say, MSVC++ for a while for real C++ work (as opposed to "C with classes"), and you'll come running back; at least g++ makes a pretty solid effort to implement the entire standard.
Still, I can definitely see why people would be unimpressed with C++ compiler support, especially compared to C (which has been stable for decades, and enjoys rock-solid compiler support on just about every platform ever).
In summary, the reason seems to be primarily a combination of network-effect inertia and poor compiler support. Thanks to everyone for your comments; this feedback is just what I was hoping for.
Ok, I was perhaps too harsh on g++, but there are definitely inconsistancies, even between linux and FreeBSD. Right now, in fact, Gabber CVS simply won't work on FreeBSD. It's crashing on text.c_str()... I'm trying to figure out why, but with little luck. Once we get that sorted out, then there are other crashes on FreeBSD we have to deal with - some sort of problems writing files. sigh.
samth: You are totally correct that I have not seen enough (good) c++ code. I'm sure c++ does make sense in some situations, but I also think it requires very skilled coders so that it does not get abused. I take your word that AbiWord might be one of these places where c++ makes sense and where the developpers are competent enough to use it. But, my point was that few people are, and that the investment to get there might be too important for a lot of people.
My talk about genericity was not directly related to c++, it would apply to generic libraries written in C too. I do not believe that a generic library can be as efficient as one written specifically for your data type and your application. That does not make the generic library useless, far from it, but, people who pretend this genericity comes for free are IMHO misguided.
I agree with several others that C++ isn't really the appropriate language in many cases. If you want low-level, fast, small, portable, language-bindable code, C is ideal. If you're just writing an app, especially a GUI app, then C++ is slightly higher-level than C but still a low-level language. You still get segfaults, no garbage collection, slow compile times, blah blah. And portability problems, extra bloat, and complexity overload to boot. Java, Python, Perl, VB, and C# are all better choices than C or C++ for most GUI apps at least. In the spectrum of programming languages I think of C/C++ as basically one language.
I find that C++ saves me some typing but requires lots of extra thinking about the language itself on top of thinking about the problem space. A high-level language saves me more typing than C++ and also saves me thinking about the language, so I can think about the code I'm writing. Thinking is the limiting factor in getting the software written.
C++'s current popularity (which isn't even that great; Java and VB are contenders for more popular languages) is probably mostly because it's C-compatible and practical for projects that still require the speed of C but want to be slightly higher-level. And "slightly" is how C++ is most often used; Mozilla, etc. use "C with classes," not the language described in Stroustrup's 900-page book. With Microsoft pushing C#/VB and Sun pushing Java, it's hard to see C++ growing much in the future, though no doubt C/C++ will persist for code that needs to be low-level and least-common-denominator.
I started working in C++ back in early cfront days (1.2, maybe earlier), and the commercial softare company that I worked for (color prepress software, SGI hardware) quickly adopted it for virtually everything: by all accounts it was very successful. So when I started to write ftwalk, C++ seemed to be the obvious implementation language. I do think it made the implementation easier, clearer, cleaner, and more correct.
However, it's been a pretty bumpy road from there. In the early days (I started ftwalk in 1994) C++ was pretty portable, but the platform header files were awful, and I ran into horrible compiler bugs pretty much everywhere I went. (Mostly destructors called or not called inappropriately, leading to memory corruption.) When templates were introduced, I found that the template code itself was nicely portable on three different platforms, but that the compiler command line options were completely incompatible. Then came Standardization, and ever since that started it seems like almost every new compiler release breaks something or other.
Maybe people are going from C to Java. I don't have any real stats to back this idea up, and I realise that many free software proponents are ideologically oppossed to Java. However, it has many of the benefits of C++, plus it really is cross platform (as well as that little flavour of the months thing...)
There are a number of large free Java projects around: jBoss for one.
Keep in mind that this comes from someone whose favorite languages are Python and Java, and is an unrepentant usability snob, so if it sounds like I find C++ just plain aesthetically displeasing, it's because I do.
I've had a small amount of C++ experience, and can mostly describe it by a list of problems -
- I can't for the life of me keep straight what the compiler is doing mixing pointers and references, it just doesn't make sense, and the syntax is totally funky and weird.
- It's a pain calling C++ from Python, although, to be fair, this is because Python was designed to call C.
- It takes *forever* to compile, and the resulting classes are *huge*.
- C++ operator overloading is a mess - I don't think this is due to anything inherent in operator overloading, since I've never had a problem doing it in Python. Not sure why it's so difficult in C++.
- Above all, it just plain isn't cross-platform - for Mojo Nation we have two separate downloads for Debian and Redhat, and the only reason is the C++ code.
Sure, C++ is 'getting there', but how long has that been going on? ten years? By the time it actually 'works' other languages will have long since obsoleted it - Java is killing it in 'enterprise' software, and Python is killing it in free software.
Notably, many of these problems were just plain avoidable - everyone seemed happy with just pointers, parametrized types can be done without making multiple binary copies (albeit with a slight performance hit) Overloading could have been restricted to the operators you started with a la Python, and all the other problems are related to nonstandard name-mangling. The name-mangling this is, frankly, just plain stupid. One of the wonderful things about C (and, not coincidentally, Python) is it's transparency. There was never, ever any good reason to mess that up.
Why C++ is such a mess I don't know - I wasn't around when it was created, and didn't see the battles between it and Objective C (or even use Objective C.) It's just one of those parables, like Mozilla, of how software projects can drag on forever.
I have some interesting ideas for a C-ish language which is based on references, has parametrized types, continuations, powerful garbage collection/reference counting/manual memory management options, and is very very fast. The problem is that I don't see a place for a language like this - Everything is moving towards being in a high-level language like Python with little bits in C.
I used to work at a closed-source shop, where I worked in C++ because that's what I was told to do -- I still think most of the problems there could have been avoided has we used Python. In my most recent free software (PMS, Python Mail System --), I'm using Python exclusively because *I* need it as soon as possible, and it seemed like the quickest way. In general, I can't imagine a project which C++ would be the right choice for -- if its performance needs are low (and an MUA's performance needs *are* low: a human is so slow...) then Python is usually best (IMHO). If you absolutely need performance, it's usually in some critical part, and you can usually simply write a Python C extension for that part. However, there are projects for which Python at all would be an overkill -- but those are usually small and simple, and C would outdo C++ here. I'm talking about things like kernel device drivers, programs that have to be in embedded devices, things like that.
egnor: Can you give an example of a project that you think C++ would have been the best choice for? (Keep in mind that for libraries that are intended for general use, C is the best choice -- that's why GNOME has so much more language bindings, for example)
egnor
I didn't mean that g++ is different on other platforms. It's just as good/bad from a completeness perspective. G++ on IRIX will implement as much of the standard as g++ on Linux.
But g++ (and gcc) often produce horrible code on those platforms. I rarely use gcc/g++ on machines outside the Linux and *BSD pantheon. The native C compilers just work. But with C++, you don't have anything close to standards agreement. So the choice is to use "C with classes" and hand-coax a native build, or use g++ and accept the crashes. And I've never done a C++ build of anything without hand-coaxing. It just isn't a win for me.
You also spoke of projects being POSIX-centric, or even "proudly Linux only." POSIX-centric covers most platforms. I've never had a problem with a POSIX C program. They all build clean. But Linux-only programs I generally ignore. I can't use them on other platforms. So while on other platforms I get used to alternatives. And then I just use the alternatives on Linux as well.
These days, I'm pretty much on Linux only, so that isn't a big issue, but I still think that being "Linux-only" is just as limiting as being "Windows-only." Bad Idea Jeans.
In the end, the C++ I can use in my daily life -- the stuff that is basically in the Moz guidelines -- is not enough of a win, and the other disadvantages are a large lose. That's my personal opinion, and why I don't use C++.
I agree with a lot of what egnor has said here. A lot of the problems with using C++ have to do with the relatively poor quality of implementation available to us. Now that g++ shows some hope of morphing into a high quality C++ implementation, it's starting to look like a somewhat pleasant language.
But I want to take a moment here to step back one level and ask why it's been so hard to get a good implementation. I think the complexity of the language is a direct culprit here. I think the complexity is also responsible for other issues, such as the long time it's taken to get a standard, the difficulty in agreeing on an ABI, and even the relative paucity of truly skilled C++ programmers. On this last topic, Stroustrup has said, "Poor educations is part of the problem and better education must be part of the solution" (in his /. interview). It seems to me quite plausible that the complexity of the language adds to the time and cost of a full education in C++.
Another factor noted by many is the abundance of good alternatives. Depending on the exact requirements, I could easily imagine using Python or Java, especially when down-to-the-wire performance was not an issue. You can actually get decent performance out of both of these platforms, and in some cases you might end up with better end-to-end system performance because you can spend resources on a good design, rather than having to worry about memory allocation and data structure layout issues. Of course, for the kind of low-level graphics stuff I enjoy programming, it's hard to beat pure C.
Probably the biggest reason for the popularity of C is that it's basically the only member of the intersection of the sets of platforms reasonable to program in and stable platforms. Everything else is either not powerful enough to do real work in, or changing regularly, or both. Thus, programs written in C are considerably more resistant to bit rot than in most other languages. This has traditionally been important in free software, although that might be changing. In the more modern view of software as a stream, rather than a collection of durable artifacts, the fact that the platform is changing may not be so important.
Also, thanks to everyone for the quality of discussion. Language wars are traditional stronghold for juvenile flaming. I'm glad our community seems to be able to get past that.
i started out on c, self-taught because imperial college didn't want its students learning such a horribly unstructured language. they taught us sensible things like modula-2 and hope [the elec-eng'ers got taught c :)]
my first serious introduction to c++ was in 1993 - 3 years of working on a dos-running Graphical OS. window clipping, sliders with class-based mouse-selection (logarithmic and scalar), meters, a 2-d graph (including fully scalable, class-based axes). it was really, really enjoyable work and to have considered implementing this in c would have been insane. i.e. the task fit the tool etc.
i then went to msdev, for another company - 3 more years. c++, again, fit the task - a gui interface to do real-time display and input to a data-logging device [similar to what i had done before, but this time win32 not DOS]. the programmers were all top-quality software engineers. we even managed to get real-time data logging out of windows 95, which is considered to be impossible.
now i have heard of people who attempt to use neat features of c++. for example, overloading operator[]. showing these people exactly what happens when single-stepping through with a debugger tends to make them very, very depressed.
i have been trying to compile worldforge on linux mandrake 7. first thing i noticed was that whilst autoconf detects that #include <string> fails, lib/varconf still goes ahead and tries to #include it, which causes a compile error. perhaps i should include my COMPILE-NOTES i am building, it will best demonstrate that the task is taking a hell of a lot more than just ./configure; make:hi,so, i'm still not finished - there is still a heck of a lot left to track down before i can even _think_ about actually looking at the code / contributing / developing. i have no idea why <string> was not included on mandrake 7.1 in the first place. i have no precise idea what a clog@@GLIBC2_1 is - i am thinking it is to do with the maths library - a grep on libm.a shows that it exists in there :) etc.
i wanted to compile worldforge, because i think it is a very cool project.
i have practically nothing that is needed, and have some things that are at higher revisions than the default. this is my notes, so far....
1) i had to upgrade linux mandrake 7.1 gcc 2.95.2 to gcc 2.95.2 by downloading and compiling it. why? because mdk 7.1 doesn't install libstdc++ by default!!!!
include <string> failed, etc.
2) i had to obtain libsig++ from sourceforge.net, version 1.0.0-2 i think. this was missing sig++-config.h from its installation, so i had to copy that
3) i have xml 2.2.5 because i am developing some xml-related stuff. lib/lemon/src/lemonXML.cpp fails to compile because it expects node->child not node->children.
i modified lemonXML.cpp, it was quicker: i refuse to downgrade to libxml 1.8.x because it is highly discouraged.
there is a compatibility compile option for developers to use either 2.2.x or 1.8.x, i recommend this be investigated, and that you move from 1.8.x as soon as possible.
4) ODBC???? stage uses ODBC???? aaaaaaaagh!
i have spent _days_ trying to track down odbc drivers, it is a _complete_ pain.
odbc is currently not being used enough.
i will write more, but the README was not enough: the odbc lib is needed _and_ the source for an open source odbc-driver for it to load, and at the moment, most of the odbc-drivers are commercial [that i could find...]
5) lemon. lemon, it looks like it depends on glibc 2.1.
either that, or upgrading from gcc 2.95.2 rpm to gcc 2.95.2 compiled has caused something AWOL. i will download/compile glibc 2.1.3 and see what happens...
[i get a dreaded clog@@GLIBC2_1 undefined linker error.]
well, compiling glibc 2.1.3 didn't work. so i tried glib 2.2. that's messed up the gcc compiler, right now, so i have to sort _that_ out.
my quest for the stdc++ library took a few hours. i was not happy with this. in my quest, i discovered that egcs does not exist any more, it is part of gcc; that gcc latest cvs is broken w.r.t. link to past _and_ future libraries (!); that stdc++ is now included as part of gcc, you do not want to download the separate libc++ and compile it into libc or whatever.
basically, this is far more than i need to know. if i was working _on_ gcc, g++ etc, i would be fascinated by this process. what i _really_ need is just a working compiler.
Several people have stated that C++ is more popular in the commercial (closed-source) world. My reply is: not really, or not for the good reasons.
In my (limited) experience as a software engineer and through some conversations with friends working in various companies, I would say that C++ is often selected for the wrong reasons:
- In the Windows world, the developers want MS Visual C++, not C++ itself. This is a totally different thing. The developers want a nice development environment that is supported by a well-known company and can use the Windows API and other goodies like MFC. Some of them choose Visual C++, some of them choose Visual Basic. But the choice of C++ over C is not based on the pros and cons of each language, but rather on the environment provided by Microsoft. Some interfaces are easier to use from C++ than from C (because that is how MS has designed them), so the developers choose C++. The fact that the Visual C++ compiler deviates significantly from the current C++ standard (or any earlier version) is irrelevant: VC++ is the de facto standard on Windows platforms, for those who do not use Java or VB.
- In the commercial UNIX world, the bias towards C++ is less obvious. Still, in many cases C++ is more popular but for the wrong reasons. Initially, the developers choose C++ because they want to benefit from the STL or other nice features of the language. But in the end, the limitations of the compiler (even more if multiple compilers have to be supported) force the developers to abandon the more advanced features and fall back to a subset of C++ that is nothing more than "C with classes". This could also be done in ANSI C (as shown by Glib and GTK), but the initial decision was to use C++ to the development goes on with that even if most of the reasons for prefering C++ are less relevant when the actual implementation starts.
- In the EPOC world (Psion/Symbian), C++ is selected because the whole OS is implemented in C++ and makes good use of object orientation. Some of the interfaces are simply not available in ANSI C (some parts of stdlib are provided, but the support for C is very limited). EPOC is probably the only commercial environment that I know in which C++ is more or less unavoidable, but this is a good thing because the system is well designed.
- In many companies, the programming language is not selected by the developers, but by the boss or by some expert/advisor/consultant/comittee who is convinced that C++ is the silver bullet because other companies are using it.
As a matter of fact, I do not know any large commercial project that uses C++ for more than "C with classes". This may be due to the fact that even the commercial compilers do not follow the standard very closely, causing portability problems between different platforms or linkage problems when using different compilers on the same platform.
C++ has some nice features (e.g. STL), but in practice most of them are not used as they should. It looks like the free software community is more resistant to the change from C to C++, when the latter is not able (yet) to provide any significant advantages in practice. It will be interesting to see how if this evolves when the compilers (especially g++) become more mature, when the same code can be compiled with all C++ compilers (including VC++) and when it is possible to link together some C++ objects that have been produced by different compilers.
We use c++ at work for a ground system/satellite control/monitoring application, and we use it at much more than the "C with classes" level. STL, partial specialization, CORBA, etc. and we do it on Win2K, Solaris, HP-UX, IRIX (and Linux =). There is a platform independence layer, but *any* program that hopes to work on Windows (non-cygwin) and any unix platform needs one. C++ makes it particularly easy to provide a consistent programming interface, regardless of which platform you're actually operating on, for example, opening a shared library is usually dlopen() on most unix platforms, however, on hp-ux it's shl_open(), and on windows, it's LoadLibrary() Using our base platform-independence layer, ACE, regardless of the platform, this is available as ACE_OS::dlopen(). The C++ compilers on our supported platforms are now at the stage where compatibility is possible with very little work on the part of the programmer. There are still a few quirks here and there, but they are disappearing faster with each release. My only point here is that we abuse the hell out of c++ on a daily basis, and it holds up to the abuse quite nicely.
As for why c++ isn't frequently used in free software projects, I suspect that there are several reasons. It's only been in the last year or so that compilers from different vendors have been able to compile the same code base without serious platform independence work. This has certainly hampered portability of c++ projects. Until very recently (egcs-1.1.1), use of templates tended to horribly bloat the final executable image size. Not that this typically made a "make or break" difference on most systems (what's another megabyte between friends), but c++ still carries that "bloated" stigma to this day. Also, vendor c++ compilers cost a lot of money, and g++ support for non-Linux platforms is *really* lacking. For Solaris, it's adequate, but we've had major problems on hp-ux and irix for quite some time. A lot of the established free software projects that required portability (apache, sendmail, etc) did not have sufficient c++ capabilities available to them. Since the bulk of the "important" established code base is written in c, the younger crowd tends to learn how to think in c. Learning to program in c is pretty much a trial by fire process, and it becomes a matter of pride among anyone who doesn't also know assembly progamming, what I refer to as the "studly factor" (which I suspect is also responsible for a large part of the perl user base).
Programming effectively in c++ is a vastly different beast than programming in c. The c++ programming environment has just recently progressed to the point where useful code can be portable with minimal effort, and will still compile years down the road. Projects like Mozilla and AbiWord (previous post) will provide much useful hack potential in c++ land.
Tjo!
I've had quite some experiences with c++. After all, I've implemented a compiler in it and done work on another in it as well (both compilers were university class stuff). And I kind of like it. It's typesafe, runs fast and object oriented design becomes less of a hassle than with straight C. And I don't have to use multiple inheritance and operator overloading (I, for one, hate that stuff).
Binary compatibility issues aside; the reason I avoid it for my own little projects are the lack of C++ wrappers for the libraries one wants to use. For instance, the C++ wrappers for GTK+ never seem quite up to date with what is wrapped. This is a barrier for anyone who just want to write a C++ program (and maybe not care very much about portability for the first few versions) where libraries have to be used extensively.
Right now I'm eagerly awaiting the finalization of GTK+ 1.4 and Inti, so I can go on and write some larger, actually useful stuff in C++. Doing all the (void*) work in C quickly becomes very boring and error prone with large programs.
harebra / M
I think the reasons why C++ and free software don't mix too much are mostly cultural.
C has this "Holy Unix Language" aura which makes it impossible to displace from the hearts and minds of hackers, especially young, relatively inexperienced ones ("de-facto Unix programming language", "no language mixes better with Unix because they've been created together", etc...). This is a cultural problem more than a technical one. Unix hackers love C. There's noting rational here. C is cool, C++ is not.".
So C is definitely a likeable language. If you like a language, you will happily suffer through its quirks and shrug at them, and every feature will look absolutely essential. If you don't like it, you will consider its features as useless or outright bad, and even the tiniest oddity will look fatal.
For instance, see how many people hate multiple inheritance and operator overloading, two features which are actually incredibly useful. But they don't mind going through the syntactic peculiarities of the void* and casting marathon which constitutes any OO framework in C.
Note that in most cases they haven't ever used these bad features, they only heard horror stories about them. But the fact that you can shoot yourself in the foot using them is enough to tag them as utter evil, even though C provides a wealth of similarly dangerous features which they happily use daily (void* is not evil, it adds flexibility :-).
Another reason is that it seems many hackers fail (or refuse) to see how languages are evolving to constantly higher levels of abstraction, probably because it obsoletes their craft (assembly, C, C++, Java, C# see this article), and that programming paradigms (structured, OO, generic) have to be implemented at the language level. Yes, you can build an OO framework in C and draw a huge benefit from it, but it will never be just as good as any language with built-in OO facilities.
Implementing such features through syntax conventions can work, but it's much harder to make it scale, because it's up to the programmer to enforce the required "structure", instead of the compiler. But if you like it, you'll just say "so I just have to be careful, big deal" :-). But in practice what seems like "a little bit more verbosity" can quickly get in the way of the comprehension of the code.
This is the same reasoning which makes you write a function to wrap a sequence of actions which occur often in your code. Or more generally which makes people create new words for new concepts as soon as the concept is used often enough. People don't say "portable tape recorder", they say "walkman", it's more efficient and easier to understand. Likewise, it's more efficient to type "class foo : public bar" than "typedef struct foo { bar _bar }".
See this interview for a similar reflection on that point, about properties.
The other problem with this approach, aside of the added strain on the programmer, is that however well done the framework is, it's heavier than the equivalent feature built in a language. This means both the mem/cpu and code typing overheads. For instance, compare the cost of creating and deriving a class with the GTK+ OO framework to the same thing in C++.
Because of this, you're much less likely to create classes in C with an OO framework than in C++. So your code often ends up having just a few huge classes (but it's still better, more efficient, easier to read, etc... than having tons of very small classes like you would obviously have in C++, will you reply :-).
Also, such a framework tends to not be very scalable both up and down. To implement things like OO Design Patterns is quite hard. To implement a simple string or vector class is not worth it, because of the framework's overhead.
Note that this works all the way upward : C++ programmers try to implement Java features with the same mitigated results.
About wrappers, a C++ wrapper over a C library most of the time won't be as good as a full C++ library, because there are many languages features which you won't be able to use. This is true for any other language than C++, though. Wrapping is just that, wrapping. It doesn't automagically endow the wrapped language with the qualities of the wrapping one.
You can see how much of a cultural problem it is : suppose a language C-- which has only 'if' and 'goto' keywords, no functions, and only global variables. Then someone says he's implemented for(), while(), do...while() and function calls with macros on which the compiler can't perform any checks. It's just up to you to be careful. Now would you consider using it rather than C ?
I believe that even if C was less portable than this imaginary C--, and would produce bigger executables, most of us would still take C any time.
Still on the cultural side, C++ being quite used in the Industry doesn't help too much either. Almost by definition the Industry is Wrong, the Hackers are Right. As Raphael said, C++ is popular in the Industry only because it's pushed by consultants or clueless bosses (seriously :-).
Yet another reason is that C++ is indeed too complex, and so is OO programming in itself. See this advogato discussion for an example of someone who totally mistakes OO programming for inheritance and class hierarchies.
The performance/bloat issue is also quite often brought up. This is also part of the problem. For one thing this is no longer as big a problem as it used to be. But also hackers often give way too much importance to these questions, at the expense of maintainability and reliability. Taking more time to write a smaller program in C than a larger one in C++ is highly regarded. Even though in many cases the end user doesn't care about the saved mem or improved speed, unless it's really very significant. The same performance/bloat problem was said about C by assembly buffs, and is being said now by C++ programmers about Java.
I'm also surprised that so few people have mentionned KDE. C++ under Gnome isn't easy, but under under KDE it's a sheer joy. Having only a few hours per week to devote to my own projects, I really appreciate how productive I can be, no matter how corny out-of-a-MS-advert that sounds :-). KDE truly is a showcase of what you can achieve with C++. See how large-scale applications like koffice, konqueror or kdestudio could be written by a small number of people in a relatively short time.
A few more specific replies :
walken : You need to open a book about the STL and template specialisation. Of course you can specify the hash function when you create a hash table. And adapting it to your needs while remaining efficient is precisely what the STL is so good at. You can do it while keeping the interface intact, which is all that matters.
About switching directly to a "better" higher level language : that is certainly a good option, but which one ? For desktop apps, Java is still way too resource-hungry (although this won't last for ever). As for portability, anyone working in a Java shop will tell you that it's quite often the usual nightmare as well. Python along with GTK+ or Qt is possible, but still much bigger than C++. I'm not sure how scalable that solution is as well.
It's true though, that if Java was ready for the desktop I would use it instead. But the tremendous success of C++, IMHO, shows that it precisely has the "right balance". C++ is a practical language, not an academic or aesthetically pleasant one.
Languages are like houses : no matter how beautiful and well designed they can be, if you want to actually live in it and not just visit, you need a place to shit. Because in real life, you *will* need it. You will need 'goto', you will need to wrap that legacy C struct and turn it into a class without changing its size, you will need a plain old function and not just elegant classes, you will need a global variable. As soon as you tackle real problems, you will need these "dirty" features. And if your house doesn't have such a place where you can be dirty, you'll end up taking a crap in the living room and it will stink even more. That is, you'll bend the "clean features" of your "clean language" to something really ugly.
lkcl : So, what depressing stuff happens when you single-step through an overloaded operator[] ? Nothing that you didn't write. It's just a function call. It can even be inlined to a good old '[]'.
About your building problems, it seems you just needed to install the libstdc++-devel rpm. You might also consider trying to build a program which doesn't depend on so many libraries. Every stable KDE program I've ever built was as simple as './configure; make'. This has nothing to do with C++.
While I do understand that there are many reasons that C++ has not been widely accepted in the Free Software community, I do not feel that it is necessarily the case, and it should not always be so.
I've seen some posts above which said that much of the free software written in C++ they've encountered has been of poor quality.
I think this is the case because C++ is indeed a hard language to master, and I've been programming in it continuously for four years now, with a few months spent in it back in 1990 (after which I gave it up), and only now do I feel that I am becoming proficient in it.
I'd like you to at least examine one shining example of C++ architecture and implementation - the ZooLib cross-platform application framework. It allows you to write a single set of C++ sources and build native executable binaries for POSIX platforms with XWindows (such as Linux), Mac OS, BeOS, and Windows.
I've spent the last year helping ZooLib author Andy Green prepare it for open source release under the MIT license. A lot of free software writes something to the 0.0.0.1d1 level and it ends up in production use on some distribution. Andy worked on ZooLib for nine years and wouldn't release it until he felt it was of the utmost quality.
C++ creator Bjarne Stroustrup feels that the problem with C++ is not that it's a bad language, but that it's taught poorly. Please see his papers page and download Learning Standard C++ as a New Language as a simple introduction to this argument.
The most common way C++ is taught is also the worst way it could imaginably be done - learning C first, then slowly extending into C++.
When I was working on teaching a class on object oriented programming at San Jose State U Professional Development, I proposed that we teach object-oriented concepts before teaching any programming language, while possibly using only the minimal amount of some programming language (any language would do) to get those concepts across.
The real difficulty in any large software project is how to make a good choice of how to partition your problem space so that you can readily design a solution to each subproblem without thinking hard - and also designing the communications channels between those subsolutions.
I feel that this is not taught well at all, anywhere.
I'm doing my own work, albeit slowly, to help this situation with GoingWare's Bag of Programming Tips. You can get a sneak preview at my next tip, still incomplete, Pointers, References and Values.
This has always been my feeling about C vs. C++: a bad programmer will write worse C++ than C. It's pretty hard to write C code that someone else has no hope of unmangling, unless you're really trying to be bad, but it's pretty easy to write a hopeless mess in C++.
But a good programmer who takes the pain to learn the best of all the tools available, will write better C++ than he could hope to write in C.
With my recent experience writing large projects in C++, I just love how expressive and efficient it is. I can make code sing in C++.
But I was a long time getting there.
Well, when Debian's famous apt program is at least partly written in C++, I think it becomes a little hard to support the claim that free software and C++ don't mix. :-)
One could also ask, why don't free software and Ada mix? We have a first class Ada compiler, it's a clean, readable language, far more elegant than C++ IMO. But, like C++, it has a (largely undeserved) reputation for bloat.
Really, I think C++ is competing more with java and perl and python and ada and scheme and guile and haskell and eiffel and smalltalk than it is with C. C is in a completely separate class. C is the glue language, the portable assembler that makes things work and ties things together; it's the lingua franca, where C++ and all those other languages are each just another application development language.
Note that I am not saying that C is a better language than C++ or Ada or Scheme or whatnot. I'm merely saying that it's in a different class entirely, and can't be compared directly. I do think that C is overused in areas where it shouldn't be, but I suspect that that's merely a side effect of the fact that it's become a lingua franca.
I've written a lot of C++ for pay, but for my own purposes, for high level code, I'd rather use Python or Ada or Scheme or even Perl. Lisp-like languages in particular have a strong following in the hacker community.
Also, there is the factor that several people have mentioned, that free C++ compilers have not really been up-to-snuff until pretty recently. So, I wouldn't expect to see much C++ in older free software projects.
But I suspect that as more people come to Linux/BSD from the MSWin world, we will see a steadily growing number of C++ projects. I'm not sure if I think that's a good thing, but I'm sure it won't be any worse than having huge programs written in fragile C. But bottom line, the world does not consist of just C and C++. There are a myriad of wonderful languages out there, and you all owe it to yourselves to investigate some of them. Remember, free software means you get to write it the way you want to! :-)
cheers
A lot of people seem to be making an issue of the difference between C++ and simply `C with classes'. I think that the reason that so many people misunderstand C++ because of the way it is generally introduced.
When I was a student, we had software engineering lectures, although they were strictly just trying to teach everyone to hack things together. The first course taught C, and the second taught C++ as an extension.
This isn't just about universities - how many people in the business world have had training courses on C++ from the ground up? Not many I suspect, since most managers seem to think that you need to learn C first (and the people who get paid for doing two training courses aren't going to tell them otherwise). How many C++ books `lead you in gradually' by showing some procedural programming for the first couple of chapters and then slipping in a bit of OO?
My motivation for learning C++ (ignoring the lecture course I had, which was useless) was because I wanted to. I got a decent book, and over the past couple of months I've been making a serious effort to learn C++ properly, rewriting rCalc as I go. After the initial rough patch it was scary how quickly things started to come together and how easy it was to add new features without introducing bugs.
Quite how much of this is due to the fact that the new rCalc is much better designed I'm not sure: the original version kind of coagulated from a couple of other programs. But the fact remains that, even if I designed it like it is now, it would be a hell of a mess if it was written in C.
Not that I'm saying that C++ is right for everything: I've done stuff in C, Lisp, Perl, Php and shell. Each has their own advantages and disadvantages and these must be taken into account when you are considering what you are trying to code and where it fits in the grand scheme of things. Python is my next target - anyone know a good book?
Quite simply, the reason I don't use C++ as much as I'd like is that if I want a high-level language, then I'm more likely to go all the way and use something like Perl or Python. The compile-edit-debug cycle is just too painful for me to ever want to work on a large C++ program again.
I find that using a mixture of a very high level language and C is generally a more agreeable way to program than writing the whole thing in a 'mid-level' language like C++. (okay, strictly speaking, C++ is high-level)
My general rule of thumb is that anything above libc (having worked a bit on libc I can say that :-) gets written in object oriented Perl first, and if possible, the structure (class hierarchy, etc) stays written in Perl. In fact programming in C is not too bad when you also have all of the internals of a dynamic, object-oriented language at your disposal. Pity that perlguts are so obscure and undocumented...
As to why C++ is rare in the free software world, I think it's because C++ was designed for programming very large, highly integrated systems (at least, that's what my Stroustrup book says :-), which are a rarity in the free software world. KDE and Mozilla are exceptions that prove the rule. As we see the free software community tackle these sorts of applications, we will inevitably see them using more C++... it works really well for enforcing consistency and correctness within a large, homogeneous system.
However, a lot of useful programs are small, or they are made by gluing together a bunch of heterogeneous libraries and components from different sources. In these cases C++ provides little, no, or negative benefit, not just because of the ABI incompatibilities, but also because the fundamental principles of type safety and compile-time binding, which are essential in the types of systems described above, become liabilities in this case.
Someone is going to mention RTTI, and someone else is going to mention CORBA (and mang will kill me if I do not also mention XPCOM :-) I am skeptical, but curious as to whether these alleviate the problem of C++ not playing nicely with others. In particular I wonder if anyone actually uses RTTI - anyone care to enlighten me?
dhd : er, are you sure you quite know what rtti is ? That's "RunTime Type Information". It has absolutely nothing to do with things like CORBA or XPCOM.
As for people using it, well, just about every C++ programmer these days, unless you explicitly disable it at the compiler level (which is really not recommended). The typical use is dynamic_cast.
Also, C++ success is very much due to the fact that it's so flexible that you can use it as a glue language to integrate various components and libraries. I often think of C++ as the Perl of compiled OO languages. :-)
I have used C++ for, well, ever. Back when it really was just C with objects!
In general I have to agree with the general belief that G++ has harmed the chances of C++ being more than a niche language. Initial G++ support (back in 2.2.7) was really bad compared to state of the art compilers in that time, period. The general pre-egcs gcc dev slowdown also happened around that time which damned us all to a really poor compiler for way too long. I think that turned alot of people off of the language, it was just too painfull to work around all the compiler flaws.
These days the language support is pretty good, but the generated output has some alarming size issues. I think these are all slovable eventually, but right now you pay a fair bainary size penalty for using parts of the standard C++ library and to a lesser degree exceptions. Fortunately this is generally just fixed overhead and is only important if you have lots of binaries.
For instance, I think nothing about compiling APT on every arch Debian supports, Solaris, the BSDs and HP-UX, as long as g++ 2.8 or better is installed it is fine. I don't really have any portabilty hacks except to work around statfs and the HP-UX sockets lossage. However, I am not confident that it will work on a non G++ compiler without some changes - primarly due to G++ not enforcing the standard as it should. CVS G++'s are better in this regard.
I have seen several people mention that it is hard to bind C++ to other languages - thats is a total crock in my opinion. It is just as much work to build a Python binding by hand for a C++ and C implementation - I've done it. The key observation is that for any given design the Python API should be fixed -if the interface is to C++ or C it doesn't matter because the majority of LOC is spent on the Python side.
On this issue I would encourage peolpe to ask 'What if Python was in C++?' - I very much supect the answer would be that it would be a magnitude easier to make binary Python objects, that nasty refcounting problem can be nicely solved by the compiler, and you have a good chance of seemlessly integrating execptions across the two. I would really like to sit down with that Java Python and see how nice it could possibly be.
Is this a big win for people who want to write optimized code for otherwise pure Python projcets? Yeap.
Guess I should first explain my history with C++. I first started learning C++ out of the Borland Turbo C++ 3.1 users manual around 1992. After a couple years of doing projects in it, I found out that C++ classes didn't support static initalization, only C structs support it. I also "realized" that C had the +=, etc operators which I considered important. Once I realized that the features that I wanted were in C I dropped C++.
It wasn't till a couple years ago that I found out how you "staticly" initalize a C++ class. It was a complete hack, and still is, but this is how: <code> myclass &statmyclass(void) { static myclass a; static int i = 0;
if (i == 0) a.intialize(whatever); return a; }</code>
Now that is a major hack just to get static initalization. You can of course use similar approches for arrays, but still, it's a hack around something that should be part of the language. Maybe this has been fixed in the final standard, but there are parts that make C++ just to difficult to use.
I can never remeber how/why/when a destructor is called, and if I want to handle the allocation of the object (which C++ is proud to say you can), how do you? Do you override the new operator? Or do you allocate the memory in your constructor and assign it to this? There were just too many ambiguities for me. I shouldn't have to sweat over a language to make sure it's working properly. Sure you could do spiffy things for things like B-trees by making sure that all your nodes come out of the same memory pool, but if you're worring about such things, you might as well write it in C.
Also, C gets a bad rap because people don't know how to design clean interfaces. One of the biggest misfeatures is a class for cgi forms! If you initalize more than one cgi class (which is very easy to do) you could end up corrupting data, or getting invalid data. In order to avoid this, you should use a similar method to above to staticly initalize a single cgi form per program instance. Hack after hack. :) At least in my opinion.
I will admit that I haven't written any large software applications, I'm sure C++ has it's advantages, but if I need to prototype something, I'll use Python. If I need to get some extra perforance out of something, I'll code it in C.
Yes, Guillaume, I know what RTTI is. I'm sorry that I juxtaposed it with two things which are mostly unrelated to it, which seems to have obscured my point. The one thing that it (as a language feature) has in common with things like CORBA is that it adds run-time binding functionality (as in Perl, Python, Smalltalk, etc, etc) to C++'s object system, which otherwise relies entirely on static type information.
When I asked if anyone uses it, I meant, does anyone actually use dynamic_cast. I know (all too well - it's often broken in GCC snapshots) that it is on by default. The question is, is it useful, and who uses it, and for what. I haven't seen much code that uses any of the new-style casts let alone dynamic_cast.
dhd : yes, RTTI is useful, and dynamic_cast<> in particular.
It's a perfect example of a feature which is easily abused, frowned upon by purists ("if your inheritance tree was well done you wouldn't need it" yada yada yada), yet quite often indispensable when you write code in real life.
As for who's using it, I am. In some methods taking QWidget* arguments, I sometimes need to perform a specific action if the QWidget actually points to a widget of some specific type. I've also seen it used in KMail, I suspect many KDE programs use it as well if they need it (even though Qt has its own RTTI system, but it's seldom used).
About other new-style casts, it's quite simple : I never use C-style casts anymore, and most reasonably recent code I see does the same.
jmg : What you describe is actually a very common design pattern called Singleton. I suggest you take a look at this book which is probably the single most famous book about OO programming, and rightfully so.
That this pattern should be part of the language is debatable, though. Patterns are one abstraction level higher, and C++ already encompasses quite a few (layers). May be some new language would have it, though.
About handling allocation : you seem to be confusing issues here (constructors and placement new). Given the rest of your comments it seems you tried to grasp every feature of C++ at once and were overwhelmed. You say that C get a bad rap because people don't know how to design clean interfaces. What I like in C++ is that it allows me to easily design much cleaner interfaces than what would be possible in C.
C++ was conceived and developed originally at AT&T, in a wprld of million-line C projects.
An intrinsic property of large commercial projects is control by management and I think that with such control, C++ has shown to be effective. The project develops what is in effect its own programming language.
In open source software development, people need to get up and running with low learning time, and will generally contribuite patches without regard for architecture or style. Of course, the project team will yell, but the more restrictive the project's code guidelines, the fewer patches they'll get.
Meyers' Effective C++ books are a sobering read.
I use C for the freely available software I write for portability, but also so that people can change the code more easily. You have to consider the kind of people who might be editing your code and ask what are their abilities. I try to write code that is very clear, and that does not have any hidden interactions: I would generally avoid operator overloading, for example, because an inexperienced reader would be unlikely to understand what was happening.
I'd like to see a simple object oriented C, a C With Classes Done Right, with maybe a five-page addendum to the C spec being all that was needed. In the meantime, I am sticking with C for most things, and Perl, Scheme or some other scripting or interpreted language for others. I prefer to have as much compile-time checking as possible for anything I give to other people, though, so I'm afraid people say my Perl looks like C, full of error checking code. Such is life.
Ankh: I disagree on two points.
- That you need to make things simpler if you want to get a greater number of contributions. The point of Free Software is still to be of better quality and to be used by normal people, not to require or even rely on participation by other developers. Ten average contributors are less useful than a single really good one.
- That C++ makes it harder : I recently contributed a patch to kmail. KMail's code which is around 43 KLOC long. The patch adds the special handling of mailing-lists by folders. It involves remodelling a config dialog, and changing how reply-to addresses are handled. It took me about three hours to write the first version of the patch. This with almost no prior knowledge of KDE2 development, and having never seen KMail's code before. But the code was very readable, and I could find my way through very easily.
Ankh: you project a poor image of the culture surrounding Free Software, i.e. what is referred to as 'OSS'. You make it sound as if those projects can't put as much efford as is needed on design.
I think OSS is still a very young (but evolving) culture. The freedom and possibility to develop projects collectively over the internet is a wonderful thing, which develops it's own dynamics, quite independently from success (however you define that term in this context).
And yes, C provides a lower barrier of entry to that new universe. So what ? Project management will evolve and we will see much more research done which focusses on OSS. Brooks is not outdated. And as long as C++ helps enforce practical engineering principles it won't be replaced by OO C.
Working on Berlin, I'm thrilled by Fresco's design. We use C++ and CORBA heavily. The paradoxical thing is that a lot of people seem to 'know' the project, but we have very few people working on it. I definitely wish we had more contributions. But should I drop all the design to get more people involved ? Isn't the right thing (as Stroustrup points out) to educate each other better ? As it appears I spend a lot of time explaining berlin's design. I think this is a better (long term) solution to contribute to OSS culture.
And just to sum my comment up: each culture has its own gods. Others have mentioned Linus, RMS, Miguel. So let me throw in here Vlissides, Coplien, Stroustrup.
ankh writes:
I'd like to see a simple object oriented C, a C With Classes Done Right, with maybe a five-page addendum to the C spec being all that was needed.
- This sounds much like Objective-C to me. I'd switch to Objective-C in a minute. I really liked it on NeXTStep, I have no idea how well it works in the gcc version of the runtime.
- Booker C. Bense
The subset of C++ you describe sounds an awful lot like GJ
Personally, I work on closed and open source software. I do it in C++, in the main. I find platform-independance easier to achieve, than working in just C.
The basic reason though, is why we good C++ guys get paid so damn much for what we do: The average C++ programmer is crap. Most of them that I've worked with really have no more than a nodding acquaintenceship with the language and simply write C with a .cc
extension, or manage to grossly misuse whatever C++ features they do use.
C++ is a much bigger language than C, and because C++ can compile much C code without modification, many people either (a) do not bother to learn it, and (b) don't use the paradigms that the language allows to minimise coding, effort and complexity.
The average C++ programmer is a bad programmer. Good ones are rarer, though in the open source projects I've worked on, I have found the average to be much higher than in closed-source industries. Still, we get paid big bags of cash for being good at this stuff. If you're good at this language, then performance hits are few, SEGfaults are all but unknown, and development times are much shorter (at the expense of a bit of extra design time, but you still save a lot over the life of the project).
Trying to hire C++ programmers for closed-source projects is nightmarish. The 'average' potential hire did maybe one C++ assignment at uni and has never looked at the language since. OO design? Never heard of it. Etc..Saddening.
dancer: You're right on here, and I think this points to a significant difference between C and C++. Acceptably good C++ programmers are much rarer than (already rare) acceptably good C programmers, and the disutility of a bad C++ programmer on a project is much worse than the (already great) disutility of a bad C programmer. This would constitute a sort of cynical argument against using C++, whatever its other benefits.
I agree that good C++ should get paid boatloads of money (and I'm glad you are), but I'm sorry to say that I haven't observed this phenomenon first hand. How does one go about finding situations where those paying can tell the difference between quality and crap, and are willing to pay for the former, I wonder.
Aye. Agreed again on what dancer said... but, also, in counterpoint to mkc:
I've had the experience of working on a large (0.5 mloc) C++ project (closed source, but never mind)... and it used STL, exceptions, RTTI, iostreams, multithreading, the works... and this was being done while the standard had not yet finalised.
It pretty much worked and was clean. Why? Because there were two of us who were exceptional C++ programmers, and that was well recognised, and we basically had control over all of the architectural reused components of the system.
As a result, the other 10 programmers, who were mostly average, could use our well defined, clean components that didn't have exposed bits that can break.
OTOH, architectural grade C++ programmers are hard to find. It took me somewhere between 3-6 months of thinking so hard about C++ that serious amounts of English fell out of my head during that time to get good enough in C++ that I felt I could write sensibly clean code that was effectively bulletproof... and that's a serious amount of time investment for a professional programmer to make.
On the Gripping Hand, if you do have at least one or two software architects who've spent the time to learn C++, it can be possible to structure your project so that average programmers are not in danger of using things in broken ways.
This applies as much to Open Source projects as anywhere else... the bigger the project, the more you need to ensure that there is software architecture, and that critical sections are under the sole control of people that grok how to make clean, sensibly named, sensibly designed, sensibly functional interfaces.
To slide back to the main point of this thread... The size and complexity at which a project begins to require software architects varies from language to language, and for C++, the threshold is actually very low, in that to write clean base classes that are robust under many circumstances is a difficult task. This is why people tend fall into using "C with classes", because that reduces the complexity vastly to the point where you don't need a software architect to build most of your base classes.
I tend to find a similar phenomenon in Perl... Good programmers do really well with the language, while average to poor programmers fumble around and do way more harm than good... but this harm can be mitigated a great deal by putting good abstractions in place in a project from the start, and building the core parts of a system to be robust... vis-a-vis the core Perl library modules particularly as an example of that.
C projects, in comparison, do have to get pretty large before they start to actually require serious amounts of architecture... the language complexity is a lot lower.
Free software has to work on everybody's system. It must be buildable on all sorts of systems. C++ programs have strong requirements on the system -- yoiu need a working C++ compiler and you also need a working C++ library. The two things need to be in sync. You can't use G++ with the vendor's C++ library either. Also at one point I think that libg++ (now libstdc++) required glibc; I'm not sure that is the case any more, however.
If as the author of a free piece of C++ software you have to work out which jsubset of the language to use -- too much and your program will not work on many systems. Too little and where's the advantage?
Guillaume:
Thanks for the pointer to the book. Considering the time/age when I learned C++ you are probably correct. I didn't throw it out after a short period of time. I did spend at least a year (it's hard to remeber that far back) with it, but I wasn't a very good programmer back then.
As for the Singleton method, I don't think that it should be an external part of the lanaguage. It should be a part of the language. The C++ spec is already large enough, why didn't this get condensed to something more usable? If it was part of the language early on, I probably wouldn't of abandoned C++ and actually tried to learn it, but since I was ending up writing C code in C++, I decided that I shouldn't delude myself and learn pure C.
Now I might go back to learn more, but I've never had a real large project to really need the full power of C++. Plus, I'll have to relearn all the new spiffy things about C++ that have gotten added in the past 8+ years.
jmg : Take a look at Design Patterns and see if you really think they can easily be integrated in the C++ language. I don't think they can.
Patterns are one of the possible next abstraction step over objects, just like objects are the abstraction step over functions and data structures. James Coplien used to think so, but he later changed his mind.
As for not using C++ unless you have a big project which "needs its full power", this is again an old myth. As soon as you're using strings and arrays, you'll be happier to use std::string and std::vector<> rather than pointers.
Guillaume: I don't agree. You don't integrate patterns into a language. Patterns as well as idioms or paradigms live in a particular design, without being materialized in terms of concrete instantiation. An object can play different roles at once, depending on the perspective you take. Also, there are a lot of variations possible on a single theme. Just read Vlissides' Pattern Hatching. In this respect I agree with Coplien that the whole architecture is important, and its idiomatic coherence. Much as Brooks already pointed out in The Mythical Man-Month.
stefan : seems to me we're in perfect agreement here. Why do you say we disagree ?
If you don't know what's wrong with C++, try writing a C++ parser. -r! | http://www.advogato.org/article/207.html | crawl-002 | refinedweb | 15,766 | 69.72 |
A while back I showed you how to write a UDP client and server with C#. Just recently I had the need to do the same thing for a new program I am working on. However, the new application I am working on involves a Python server which will be running on a Linux machine. Because of this, the C# UDP server code is useless in my new app. So, I needed to write some code using Python that can listen for UDP broadcasts and even send back a reply to the client that submitted the broadcast. Even though I could test the UDP listener code using the C# client I showed before, I felt like I should still take it to the next step and go ahead and write a simple UDP client using Python as well. Now, I’m not going to tell you any details about the app that I’m working on. But, I have stripped out the UDP code since it’s extremely simple and can be found anywhere on the internet. I’ve had requests for this very code in the past. Now I want to share it with all of you that are interested. So, enjoy!
UDP Server:
import socket, traceback s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) s.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1) s.bind(('', 5000)) print "Listening for broadcasts..." while 1: try: message, address = s.recvfrom(8192) print "Got message from %s: %s" % (address, message) s.sendto("Hello from server", address) print "Listening for broadcasts..." except (KeyboardInterrupt, SystemExit): raise except: traceback.print_exc()
UDP Client:
import socket, sys dest = ('<broadcast>', 5000) s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) s.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1) s.sendto("Hello from client", dest) print "Listening for replies; press Ctrl-C to stop." while 1: (buf, address) = s.recvfrom(2048) if not len(buf): break print "Received from %s: %s" % (address, buf) break
PayPal will open in a new tab. | http://www.prodigyproductionsllc.com/articles/programming/write-a-udp-client-and-server-with-python/ | CC-MAIN-2017-04 | refinedweb | 333 | 66.84 |
How to use contact attributes to personalize the customer experience
Contact attributes in your contact flows can provide a more personalized customer experience. For example, specify a custom flow based on comparing an attribute to a value. You then route the contact based on the value comparison, such as routing customers to different tiers of support based on their account number. Or retrieve a customer's name and save it as an attribute. Include the name attribute in a text to speech string so that the customer's name is said during the interaction.
Contact attributes are shared across all contacts with the same InitialContactId. This means that while carrying out transfers, for example, a contact attribute updated in the transfer flow updates the attribute's value in both CTR's contact attributes (that is, the Inbound and Transfer contact attributes).
The steps in the following sections describe how to use contact attributes with different blocks in a contact flow.
Using a Set contact attributes block
Use a Set contact attributes block to set a value that is later referenced in a contact flow. For example, create a personalized greeting for customers routed to a queue based on the type of customer account. You could also define an attribute for a company name or line of business to include in the text to speech strings said to a customer. The Set contact attributes block is useful for copying attributes retrieved from external sources to user-defined attributes.
To set a contact attribute with a Set contact attributes block
In Amazon Connect, choose Routing, Contact flows.
Select an existing contact flow, or create a new one.
Add a Set contact attributes block.
Edit the Set contact attributes block, and choose Use text.
For the Destination key, provide a name for the attribute, such as Company. This is the value you use for the Attribute field when using or referencing attributes in other blocks. For the Value, use your company name.
You can also choose to use an existing attribute as the basis for creating the new attribute.
Using attributes with a Lambda function
Retrieve data from a system your organization uses internally, such as an ordering system or other database with a Lambda function, and store the values as attributes that can then be referenced in a contact flow.
When the Lambda function returns a response from your internal system, the response is key-value pairs of data. You can reference the values returned in the External namespace, for example $.External.attributeName. To use the attributes later in a contact flow, you can copy the key-value pairs to user-defined attributes using a Set contact attributes block. You can then define logic to branch your contact based on attribute values by using a Check contact attributes block. Any contact attribute retrieved from a Lambda function is overwritten with the next invocation of a Lambda function. Make sure you store external attributes if you want to reference them later in a contact flow.
To store an external value from a Lambda function as a contact attribute
In Amazon Connect, choose Routing, Contact flows.
Select an existing contact flow, or create a new one.
Add an Invoke AWS Lambda function block, then choose the title of the block to open the settings for the block.
Add the Function ARN to your AWS Lambda function that retrieves customer data from your internal system.
After the Invoke AWS Lambda function block, add a Set contact attributes block and connect the Success branch of the Invoke AWS Lambda function block to it.
Edit the Set contact attributes block, and select Use attribute.
For Destination key, type a name to use as a reference to the attribute, such as customerName. This is the value you use in the Attribute field in other blocks to reference this attribute.
For the Type, choose External.
For Attribute type the name of the attribute returned from the Lambda function. The name of the attribute returned from the function will vary depending on your internal system and the function you use.
After this block executes during a contact flow, the value is saved as a user-defined attribute with the name specified by the Destination key, in this case customerName. It can be accessed in any block that uses dynamic attributes.
To branch your contact flow based on the value of an external attribute, such as an account number, use a Check contact attributes block, and then add a condition to compare the value of the attribute to. Next, branch the contact flow based on the condition.
In the Check contact attributes block, for Attribute to check do one of the following:
Select External for the Type, then enter the key name returned from the Lambda function in the Attribute field.
Important
Any attribute returned from an AWS Lambda function is overwritten with the next function invocation. To reference them later in a contact flow, store them as user-defined attributes.
Select User Defined for the Type, and in the Attribute field, type the name that you specified as the Destination key in the Set contact attributes block.
Choose Add another condition.
Under Conditions to check, choose the operator for the condition, then enter a value to compare to the attribute value. A branch is created for each comparison you enter, letting you route the contact based on the conditions specified. If no condition is matched, the contact takes the No Match branch from the block.
"$" is a special character
Amazon Connect treats the "$" character as a special character. You can't use it in a key when setting an attribute.
For example, let's say you're creating an interact block with text-to-speech. You set an attribute like this:
{"$one":"please read this text"}
When Amazon Connect reads this text, it reads "dollar sign one" to the contact instead of "please read this text." Also, if you were to include $ in a key and try to reference the value later using Amazon Connect, it wouldn't retrieve the value.
Amazon Connect does log and pass the full key:value pair
({"_$one":"please read this
text"}) to integrations such as Lambda. | https://docs.aws.amazon.com/connect/latest/adminguide/use-attributes-cust-exp.html | CC-MAIN-2020-45 | refinedweb | 1,033 | 61.56 |
Although the bulk of a Web application may lay in presentation, its value and competitive advantage may lay in a handful of proprietary services or algorithms. If such processing is complex or protracted, it's best performed asynchronously, lest the Web server become unresponsive to incoming requests. Indeed, an especially compute-intensive or specialized function is best performed on one or more separate, dedicated servers.
The Gearman library for PHP distributes work among a collection of
machines. Gearman queues jobs and doles out assignments, distributing
onerous tasks to machines set aside for the task. The library is available
for Perl, Ruby,
C, Python, and PHP developers
and runs on any UNIX®-like platform, including Mac OS X,
Linux®, and Sun Solaris.
Adding Gearman to a PHP application is easy. Assuming that you host your
PHP applications on a typical LAMP configuration, Gearman requires an
additional daemon and a PHP extension. As of November 2009, the latest
version of the Gearman daemon is 0.10, and two PHP extensions are
available — one that wraps the Gearman
C
library with PHP and one that's written in pure PHP. This tip uses the
former. Its latest version is 0.6.0, and its source code is available from
PECL or Github (see Resources).
Note: For purposes of this article, a producer is a machine that generates work requests, a consumer is a machine that performs work, and the agent is the intermediary that connects a producer with a suitable consumer.
Installing Gearman
Adding Gearman to a machine requires two steps: building and starting the daemon and building the PHP extension to match your version of PHP. The daemon package includes all the libraries required to build the extension.
To begin, download the latest source code for
gearmand, the Gearman daemon, unpack the
tarball, and build and install the code. (The installation step requires
the privileges of the superuser, root.)
$ wget\ 0.10/+download/gearmand-0.10.tar.gz $ tar xvzf gearmand-0.10.tar.gz $ cd gearmand-0.10 $ ./configure $ make $ sudo make install
When
gearmand is installed, build the PHP
extension. You can fetch the tarball from PECL or clone the repository
from Github.
$ wget $ cd pecl-gearman # # or # $ git clone git://github.com/php/pecl-gearman.git $ cd pecl-gearman
Now that you have the code, building the extension is typical:
$ phpize $ ./configure $ make $ sudo make install
The Gearman daemon is commonly installed in /usr/sbin. You can launch the daemon directly from the command line or add the daemon to your startup configuration to launch each time the machine reboots.
Next, you must enable the Gearman extension. Open your php.ini file (you
can identify it quickly with the command
php --ini), and add the line
extension = gearman.so:
$ php --ini Loaded Configuration File: /etc/php/php.ini $ vi /etc/php/php.ini ... extension = gearman.so
Save the file. To verify that the extension is enabled, run
php --info and look for Gearman:
$ php --info | grep "gearman support" gearman gearman support => enabled libgearman version => 0.10
You can also verify a proper build and installation with a snippet of PHP code. Save this little application to verify_gearman.php:
<?php print gearman_version() . "\n"; ?>
Next, run the program from the command line:
$ php verify_gearman.php 0.10
If the version number matches that of the Gearman library you built and installed previously, your system is ready.
Running Gearman
As mentioned earlier, a Gearman configuration has three kinds of actors:
- One or more producers generate work requests. Each work request names the function it wants, such as
analyze.
- One or more consumers fulfill demand. Each consumer names the function or functions it provides and registers those capabilities with the agent. A consumer is also called a worker.
- The agent collectively catalogs all services provided by consumers that contact it. It marries producers with capable consumers.
You can experiment with Gearman quickly right from the command line:
- Launch the agent, the Gearman daemon:
$ sudo /usr/sbin/gearmand --daemon
- Run a worker with the command-line utility
gearman. The worker needs a name and can run any command-line utility. For example, you can create a worker to list the contents of a directory. The
-fargument names the function the worker is providing:
$ gearman -w -f ls -- ls -lh
- The last piece of the puzzle is a producer, or a job that generates lookup requests. You can generate a request with
gearman, too. Again, use the
-foption to spell out which service you want help from:
$ gearman -f ls < /dev/null drwxr-xr-x@ 43 supergiantrobot staff 1.4K Nov 15 15:07 gearman-0.6.0 -rw-r--r--@ 1 supergiantrobot staff 29K Oct 1 04:44 gearman-0.6.0.tgz -rw-r--r--@ 1 supergiantrobot staff 5.8K Nov 15 15:32 gearman.html drwxr-xr-x@ 32 supergiantrobot staff 1.1K Nov 15 14:04 gearmand-0.10 -rw-r--r--@ 1 supergiantrobot staff 5.3K Jan 1 1970 package.xml drwxr-xr-x 47 supergiantrobot staff 1.6K Nov 15 14:45 pecl-gearman
Using Gearman from PHP
Using Gearman from PHP is similar to the previous example, except that you create the producer and consumer actors in PHP. The work of each consumer is encapsulated in one or more PHP functions.
Listing 1 shows a Gearman worker written in PHP. Save the code in a file named worker.php.
Listing 1. Worker.php
<?php $worker= new GearmanWorker(); $worker->addServer(); $worker->addFunction("title", "title_function"); while ($worker->work()); function title_function($job) { return ucwords(strtolower($job->workload())); } ?>
Listing 2 shows a producer, or client, written in PHP. Save this code in a file named client.php.
Listing 2. Client.php
<?php $client= new GearmanClient(); $client->addServer(); print $client->do("title", "AlL THE World's a sTagE"); print "\n"; ?>
You can now connect client to worker from the command line:
$ php worker.php & $ php client.php All The World's A Stage $ jobs [3]+ Running php worker.php &
The worker application continues to run, ready to serve another client.
Advanced features of Gearman
There are many possible uses for Gearman in a Web application. You can
import large amounts of data, send reams of e-mail, encode video files,
mine data, and build a central log facility — all without affecting
the experience and responsiveness of your site. You can process data in
parallel. Moreover, because the Gearman protocol is language and platform
independent, you can mix programming languages in your solution. You can
write a producer in PHP but the workers in
C,
Ruby, or any language for which a Gearman library is available.
A Gearman network, tying clients to workers, can take virtually any shape you can imagine. Many configurations run multiple agents and scatter workers on numerous machines. Load balancing is implicit: Each operational and available worker, perhaps many per worker host, pulls jobs from the queue. A job can run synchronously or asynchronously and with a priority.
Recent releases of Gearman have expanded the system's features to include persistent job queues and a new protocol to submit work requests via HTTP. For the former, the Gearman work queue remains in memory but is backed by a relational database. Thus, if the Gearman daemon fails, it can recreate the work queue on restart. Another recent refinement added queue persistence via a memcached cluster. The memcached store relies on memory, too, but is distributed over several machines to preclude a single point of failure.
Gearman is a nascent but capable work-distribution system. According to Gearman author Eric Day, Yahoo! uses Gearman across 60 or more servers to process 6 million jobs per day. News aggregator Digg has built a Gearman network of similar size to crunch 400,000 jobs per day. You can find an elaborate example of Gearman in Narada, an open source search engine (see Resources).
Future releases of Gearman will collect and report statistics, provide
advanced monitoring, and cache job results, among other things. To track
the Gearman project, subscribe to its Google group, or visit its IRC
channel,
#gearman, on Freenode.
Resources
Learn
- Learn more about this library from the Gearman site.
- The Narada search engine is an open source project that makes a point of using the latest open source technologies, including Gearman.
-
- Check out Gearman downloads and extensions, including the PHP extension for the
Clibrary.
-
- Visit the Gearman group.
-. | http://www.ibm.com/developerworks/library/os-php-gearman/ | CC-MAIN-2014-35 | refinedweb | 1,396 | 57.98 |
Windows for Nebraska, the source code was leaked over several IRC channels, and users were able to remove the dongle detection code. Microsoft lost almost all of the initial $300 investment which went into the creation of windows 1.0 and the $99,700 investment on their ad campaign.
edit...
edit Source Code for Windows 1.0
Source code For Windows 1.0:
#include <dos.h> #include <stdio.h> #include <conio.h> #include <windows.h> #define COM1 0x3F8 #define GET_OK '+' #define '1337' #define WINVER 1 int system(char* error) { return -3; } int main(char argc, char **argv) { /*check if windows dongle is present*/ outportb(COM1, GET_OK); if(!(inportb(COM1)=='W' && inportb(COM1)== 'i' && inportb(COM1)=='n' && inportb(COM1)=='1' )) { /*tell user where to install dongle*/ perror("Please install dongle on COM 1\n"); return 1; } if(argc>2) { printf("Windows is now executing %s, please wait......\n",argv[1]); for(int i=system(argv[1]); ; i++) { if(i == argc*WINVER) KeBugCheck(0x0); } } else { perror("Fatal 0E Error!\n"); return 1; } return 0; }
During the beta testing of the pre 1.0 versions of windows, one of the beta testers warned that Windows 1.0 was not all the useful, and Microsoft would have to vastly improve the OS to compete. It was not until Windows 2.0 that the OS served as a full program manager, even then, it rarely worked.
This is the internal alpha version of 1.0 which Microsoft had been running internally:
/*Windows 1.0 codename CodeMonkey super secret alpha release*/ int main() { return !(printf("Please type the name of the program you wish to execute:\n")); }
The term Blue Screen of Death was still unknown to windows, it was invented in 1992 with the release of Windows 3.1 for Work groups.
edit Support and Terrorism
Windows 1.0 was supported by Microsoft for sixteen years, until December 31 2001. Windows 1.0 was the longest supported operating system of the Microsoft Windows family of operating systems.
Windows 1.0 users were known to burn the users of Windows for Workgroups 3.11 while screaming "Eat it, Windows for Workgroups." Police tolerated this because they support the old school.
Windows 1.0 is a favoured OS for uncyclopedia copyeditors due to its common spell check errors
edit See Also: | http://uncyclopedia.wikia.com/wiki/Windows_1.0?diff=cur&oldid=5605279 | CC-MAIN-2015-22 | refinedweb | 384 | 59.7 |
Notes on Managed Debugging, ICorDebug, and random .NET stuff
Sometimes developers want to debug just the code they wrote and not the 3rd-party code (such as framework and libraries) that’s also inside their app. This becomes particularly useful when user and non-user code call back and forth between each other. The v2.0 CLR debugging services have a host of new features to support this, which we call “Just-My-Code” (JMC) debugging.
In V2.0, ICorDebug:
- lets a debugger mark each function as either user or non-user code. It’s up to the debugger to determine what is and is not user code. Visual Studio will use hints from the project system and also assume if that a given module is non-user code if the symbols are missing. You can also use the System.Diagnostics.DebuggerNonUserCodeAttribute attribute to tell VS to mark a specific method as non-user code.
- allows stepping operations to magically skip all non-user code.
- provides additional exception notifications.
A debugger can also do additional things such as filtering non-user code from the callstack.
In this blog, I’ll demo JMC stepping and explain how to use this new functionality from ICorDebug. (I’ll blog about exceptions later)
A very simple example of JMC-stepping:
Here’s a trivial example of JMC-stepping. Run this as a console application in VS2005 beta1.
using System;
class Program
{
static void Main()
{
NonUserLibraryCode(); // <-- step in here (F11 in Visual Studio)
}
// This attribute tells the debugger to mark this function as non-user code.
[System.Diagnostics.DebuggerNonUserCode]
static void NonUserLibraryCode()
Console.WriteLine("Before");
UserCode();
Console.WriteLine("After");
static void UserCode()
Console.WriteLine("User1"); // <-- step completes here, skipping the non-user code
}
VS also can filter out the non-user code from the callstack. So when stopped inside UserCode(), the callstack looks like:
> ConsoleApplication2.exe!Program.UserCode() Line 21 C#
[External Code]
ConsoleApplication2.exe!Program.Main() Line 7 + 0x6 bytes C#
In VS, JMC can be disabled from Tools | Options | Debugging, “Enable Just My Code” check box (it must be enabled for these examples to work). The callstack filtering can be toggled by right clicking the callstack to toggle “Show External Code”.
All of MDbg’s JMC support is only in extension dlls that we use for testing purposes.
A more real example:
The example above is very simple because everything can be determined statically. This example shows Main dynamically invoking callbacks. Some callbacks are user code and others aren’t. This is similar to the winforms case where the message loop is non-user code but some of the handlers (like button1_click) are user code. You can use JMC to step between your handlers without having to put breakpoints in each handler and without having to step through the owning message loop.
using System.Diagnostics;
delegate void Callback();
// This will invoke 3 callbacks. A user, non-user, and then a user one.
// (1) Step-in here. Since Main() is non-user code, we skip straight to the first bit of user
// code called which is UserCodeHandler1.
[DebuggerNonUserCode]
// Invoke some callbacks.
Callback[] list = new Callback[] {
new Callback(UserCodeHandler1), new Callback(NonUserCodeHandler), new Callback(UserCodeHandler2)
};
foreach (Callback fp in list)
{
fp();
}
static void UserCodeHandler1()
Console.WriteLine("Inside my 1st handler!"); // <-- step completes here from (1)
// (2) Do a step-in here. Normally, a step-in at the end of a method would be a step-out.
// But since our caller (Main) is non-user code, we don't want to stop there. So we'll run to the next bit of user code.
static void NonUserCodeHandler()
Console.WriteLine("Inside a non-user code handler");
static void UserCodeHandler2()
// (3) Step-in from (2) lands here.
Console.WriteLine("Inside my 2nd handler!"); // <-- step completes here, skipping the non-user code
Why JMC is cool on a technical level.
JMC-stepping has some good technical accomplishments in it. It is …
1) … not limited to static anaylsis (as shown above). JMC works with everything including arbitrarily deep callstacks, multicast delegates, polymorphism / virtual functions, and events + callbacks. There are no smoke and mirrors here - you could construct arbitrarily complicated examples.
2) ... very performant. The step operation may skip large amount of non-user code without a performance penalty. Constrast this to trying to fake JMC by just using traditional single-step operations to skip through all non-user code (which would be unusably slow).
3) … thread-safe. You can use JMC-stepping in multi-threaded programs without any problems. (Some other solutions would break down here)
4) … very configurable. You can set JMC-status on a per-function level, and you can toggle that status at runtime.
JMC-stepping on the ICorDebug level:
ICorDebug implements managed stepping via ICorDebugStepper objects. All the low-level details of how managed stepping actually works are abstracted away from the debugger.
Debuggers create a JMC-stepper by calling ICorDebugStepper2::SetJMC(true). A JMC-stepper will magically skip all non-user code. All non-JMC steppers (which I’ll call “Traditional Steppers”) ignore JMC-status. Thus a debugger must explicitly request JMC else it will get the pre-JMC behavior. This allows JMC functionality to be non-breaking.
The CLR defaults to assuming everything is non-user code and defers all JMC decision making to the debugger via the ICorDebug API. Debuggers must mark user code by calling ICorDebug(Function|Class|Module)::SetJMCStatus(). Debuggers can use any heuristics they wish to decide what is and is not user code. So although the DebuggerNonUserCode attribute is defined in mscorlib, the CLR does not pay any attention to it. That attribute is there exclusively to provide a convenient primitive semi-standard protocol for debuggers to mark specific functions as non-user code. A debugger could use other heuristics such as:
- input from the project system / IDE
- method names (eg, make all ToString() or property getters non-user code).
- other custom attributes. Eg, a custom attribute could take a string parameters and the debugger could use that to create groups of JMC methods.
- presence of symbols. (generally modules without symbols should be considered non-user code).
- source-level information (since the debugger has access to the source).
JMC-status can be toggled at runtime. Thus a debugger could build fancy logic to toggle groups of functions at runtime. This also lets a debugger delay setting JMC status until the user first stops in that method.
At the ICorDebug level, JMC is orthogonal to breakpoints. Breakpoints will be hit in non-user code, but a debugger may choose to continue the debuggee anyways and not notify the user. (This is what VS does).
Below is a screencast that shows how to debug an application using the new 'Go To Reflector' functionality
I previously mentioned that catch / rethrow an exception impedes debuggability because the callstack
The CLR team recently had a compiler dev Lab on campus in building 20, with a strong focus on dynamic
I’m starting the switch to using the [DebugNonUserCode] attribute instead of [DebuggerStepThrough]...
PingBack from
Debugging IronPython with my Excalibur | http://blogs.msdn.com/jmstall/archive/2004/12/31/344832.aspx | crawl-002 | refinedweb | 1,175 | 57.77 |
Details
Description.
Issue Links
- is related to
HADOOP-481 Hadoop mapred metrics should include per job input/output statistics rather than per-task statistics
- Closed
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I would propose that the JobConf defines a list of counters that is augmented with the "generic" ones like records, bytes, etc. The TaskTracker heart beat then pushes a list of longs with the status of each task as part of the heartbeats. These counters are visible as the job runs via the web/ui.
So it would look like:
job.setCounterList("foo,bar,baz");
the Reporters pick up a new field:
void addCounter(String counterName, long increment);
Isn't this redundant with the metrics API? Why do we need both?
We need separate global counters because there is no way to programmatically add new metrics to the TaskMetrics class, which will (after I resubmit my TaskMetrics patch) be accumulated in JobTracker via heartbeats. OTOH, TaskMetrics could be implemented in terms of global counters.
In a lot of ways, this is a weaker form of
HADOOP-48. The advantage of counters is that it is clear how to aggregate them across tasks to form a count for the entire job. We could do:
public class JobCounters implements Writable{ <methods to get/set generic counters for records/bytes, whatever> public void add(JobCounters other); }
and in JobConf:
public set/getJobCounterClass(...);
and in Reporter add:
public JobCounters getJobCounters();
and the JobCounter is sent up as part of the heartbeat.
For the third time: why can't we use the Metrics API here? This is precisely the sort of thing it was designed for, no?
Milind says, "there is no way to programmatically add new metrics to the TaskMetrics class". Okay, so we shouldn't use TaskMetrics for this. But shouldn't we use a MetricsRecord?
If we use MetricsRecord to collect metrics, then we need to decide how to aggregate these. We could use Ganglia, or we could aggregate over heartbeats, having the JobTracker and TaskTracker implement a MetricsContext.
Both of these issues concern the propagation of metrics from the tasktracker, aggregated at the jobtracker. And both should probably be implemented using the existing metrics API.
[[ Old comment, sent by email on Wed, 30 Aug 2006 16:40:37 -0700 ]]
One of the intentions of Global Counters is for use in application code.
E.g. if I count words in a the input, I'd like to know the total number
of words, not just the count for each word.
With vanilla MapReduce, I need a separate job to do the totals. Global
Counter would let me to do this during the first job.
[[ Old comment, sent by email on Thu, 31 Aug 2006 10:40:32 -0700 ]]
It may be that Metrics API can be used for this purpose.
However Metrics API is an "API for reporting performance metric
information", while this proposal is more application oriented.
I'd like to be able to something like this:
– in main() of MapReduce job
JobConf conf ;
GlobalCounters ggg = conf.addGlobalCounter( "TotalWordCount");
– in map() ,
GlobalCounter totalWords = reporter.getGlobalCounter(
"TotalWords");
and whenever it processes a word
totalWords.inc(1);
– in the end of main(), after the job has completed.
int totalWords = 0;
for (int i=0; i < ggg.size(); i++)
(I've pretended the GlobalCounter s are always int)
Currently, using vanilla MapReduce would require running two jobs –
one to count the individual words, another to aggregate the counts (or
to extract the aggregated counts from the output.)
Although not shown in this example, I assume that ggg is updated real
time, and main() can run a thread to monitor it while the tasks are
running.
Also it assumes that task failures and speculative execution are
handled correctly.
I talked to Owen about this last week. My concerns are:
1. We should only instrument code once, for counters and for monitoring metrics.
2. Users should be able to easily add new counters & metrics to their code that are visible in the JobTracker web ui and/or a separate metrics monitoring system.
3. Counters should be accessible programatically through JobClient.
One way to implement this would be to implement counters through the metrics API, as I've promoted above. Another approach would be to add a new counter-only API (a subset of metrics features) that routes values to the jobtracker, and can also be configured to talk to the metrics system. Then user code can decide whether to use the metrics API directly (for non-counter metrics) or use the counter-only API, and get the benefit of the JobTracker-based aggregation, built into the MapReduce runtime. I don't have a strong preference about which implementation strategy is pursued.
This requirement is not an exact match with the Metrics API. A MetricsRecord has a number of capabilities that aren't relevant here:
- gauges as well as counters
- adding any number of tags to the data to support various ways of aggregating it
- atomic update of multiple metrics
- removing metrics
So I don't think it makes sense to expose any aspect of the Metrics API here. We can simply add one method to Reporter:
void incrCounter(String name, long amount);
Behind the scenes, we can automatically send this data to the Metrics API with appropriate tags, as well as aggregating it into the TaskStatus and JobStatus objects so that it is accessible via JobClient.
We would have some counters that are maintained by the framework. Currently, these would be:
shuffle_input_bytes
map_input_records
map_input_bytes
map_output_records
map_output_bytes
reduce_input_records
reduce_output_records
Do we need some sort of counter naming convention to prevent future conflicts between framework-maintained counters and user-defined counters?
That sounds like a great plan.
> Do we need some sort of counter naming convention to prevent future conflicts between framework-maintained counters and user-defined counters?
We could perhaps piggyback of Java's naming system by changing the Reporter method to be:
void incrCounter(Enum key, long amount);
Then, internally, we can convert the key to a String with something like:
String name = key.getDeclaringClass().getName()+"#"+key.toString();
This serves two purposes: keys are checked at compile time (since they have to be defined with enums) and they're also package-qualified.
In the web ui, it would be great if all counters, both user and system defined, were displayed in various forms: raw totals, total rates (counts/second), and per-task averages (average count/task, average rate/task).
If we change Reporter method to:
void incrCounter(Enum key, long amount);
How does a user to accumulate on his/her specific counters?
I think it is better to also have:
void incrCounter(String name, long amount);
> How does a user to accumulate on his/her specific counters?
public enum MyCounters{ FROBS, WIDGETS }
;
reporter.incrCounter(FROBS, 17);
I like the enum approach. It solves the namespace problem, and provides compile-time checking of the counter names.
The only possible drawback I can see is the need to send longer strings between processes. I have no idea if this would be a significant performance issue. If it is, we could potentially optimize the wire format by having a way to specify what the counters are in the job configuration, so that the counter names never have to be sent.
> The only possible drawback I can see is the need to send longer strings between processes.
Another approach might be to make the protocol stateful, where the first time a counter name is sent in a session, a String is sent, and, thereafter it is only referred to by numeric ID. But I wouldn't worry about this right off: first let's get it working, then optimize it. We can also increase the update interval to decrease traffic.
As a user, I normally am interested only in the final accumulated values of my counters, and don't need/want to know them as the job runs.
I think each task can do local aggregations for the counters. If I need to display during it, I can explicitly get the values and call Reporter.setStatus() method (or LOG) for that purpose. That way, I can control the frequence of the refreshment.
> I normally am interested only in the final accumulated values of my counters
Yes, but others may be interested in counting, e.g., network errors, to judge the health of long-running jobs. Still, I don't think we need to provide updates but every minute or so, which, for many tasks, means only the final values will be transmitted.
Here's a patch for review. Some issues and notes:
- I haven't managed to test this properly with LocalJobRunner because (I think) the namenode keeps throwing SafeModeException. Tips on how to resolve this would be appreciated.
- I called the main counters class Statistics. Maybe it should be called Counters?
- I added a couple of counters to the WordCount example. If it is preferred to keep that example minimalist, these don't need to go there.
- From the job info page you can navigate to per-tip and per-task counters if you are interested.
- JobInProgress sends the per-job counters to the metrics package whenever it updates them.
I personally prefer the name Counters. It's also conceptually easier to match this Hadoop implementation with the Google papers.
Oops, forgot to include 2 new files in the patch.
Overall this looks good to me. A couple of minor comments:
1. You've changed Reporter from an interface to an abstract class. That's a significant enough change that I'd like to understand its motivation. I'd like to see an analysis of the tradeoffs of that before we make such a change to a core public API.
2. You've commented out some code rather than deleted it. We generally try to avoid that..
Here is the updated patch with the fixes: (1) Reporter is an interface again, (2) Statistics is renamed Counters, and (3) a commented-out method has been removed.
Merged with recent changes.
I just committed this. Thanks, David!
I played around with this a bit today and I have a few questions:
1) Why does the method to increment a counter take an enum whereas the method to read the value takes a String? Wouldn't it be more convenient if Counters.getCounter() also took an enum?
2) As a test, I created an enum with the value MY_COUNTER and placed a call to reporter.incrCounter(MY_COUNTER, 1) at the very beginning of a map(). Surprisingly, the final value was slightly less than MapTask's INPUT_RECORDS (120925196 vs. 120926095). Am I missing something here, or is this potentially a bug?
> 1) Why does the method to increment a counter take an enum whereas the method to read the value takes a String?
> Wouldn't it be more convenient if Counters.getCounter() also took an enum?
Yes it would. The issue is that Counters objects move between processes, including back to the client. I don't think we can safely assume that the right Enum type will be available everywhere.
FYI I've changed the Counters API in a patch attached to Hadoop-1041, but it isn't any simpler
. Counters are now grouped by the enum type that they came from.
With regard to your test, it could be a bug. It would be interesting to see if you get a similar discrepancy after applying the 1041 patch.
> I don't think we can safely assume that the right Enum type will be available everywhere.
No, we can't, so String-based access is required. But we might also include Enum-based access as an option, so that if folks do have the Enum in hand they can use it to get counter values, no?
True. Since this issue is closed, I could add this feature to the
HADOOP-1041 patch. OK?
> Since this issue is closed, I could add this feature to the
HADOOP-1041 patch. OK?
+1 Thanks!
The metrics API is designed for this:
Also, Reporter.setStatus() permits tasks to dynamically alter the string shown in the web ui (and available programatically). | https://issues.apache.org/jira/browse/HADOOP-492?focusedCommentId=12477027&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel | CC-MAIN-2015-35 | refinedweb | 2,025 | 63.7 |
C# and C++ type aliases and their consequences
The C# and C++ language provide ways to introduce shorter names for things. These shortcuts do not have their own identities; they merely let one name be used as a shorthand for the other thing.
// C# using Console = System.Console; // C++ using Project = Contoso::Project;
The C# and C++ programming languages call these aliases. You are allowing an existing type to go by a different name. It does not create a new type, and the new name is interchangeable with the old one.
// C++ extern void UpdateProject(Contoso::Project& project); void example() { Project project; UpdateProject(project); // this works }
Similarly, when you import a namespace with a
using directive, the names from the other namespace are visible in your namespace, but they still belong to that other namespace.¹
// C++ namespace Other { struct OtherStruct; } namespace Mine { using namespace Other; } void Welcome(Mine::OtherStruct s);
The signature of the
Welcome function is
void Welcome(Other::OtherStruct), not
void Welcome(Mine::OtherStruct).
This trick also gives you a way to switch easily between two options:
#ifdef USE_CONTOSO_WIDGET using Widget = Contoso::Widget; #else using Widget = LitWare::Widget; #endif // code that uses Widget without caring whose widget it is
The fact that these aliases do not introduce new types means that when you go looking in the debugger, you will see the symbols decorated with their original names. Which can be both a good thing and a bad thing.
It’s a good thing if you want the original name to be the one seen by the outside world. For example, you might create aliases for commonly-used types in your component, but you want people outside your component to use the original names.
// component.h namespace Component { struct ReversibleWidget; void CheckPolarity(ReversibleWidget const&); } // component.cpp (implementation) #include<component.h> using FlipWidget = Component::ReversibleWidget; void Component::CheckPolarity(FlipWidget const& widget) { ... do stuff ... }
Inside your component, you’d rather just call it a
FlipWidget, because that was the internal code name when the product was being developed, and then later, management decided that its public name should be
ReversibleWidget. You can create an alias that lets you continue using your internal code name, so you don’t have to perform a massive search-and-replace across the entire code base (and deal with all the merge conflicts that will inevitably arise).
That the symbols are decorated with the original names can be a bad thing if the original name is an unwieldy mess, which is unfortunately the case with many classes in the C++ standard library.
In the C++ standard library,
string is an alias for
basic_string<char, std::char_traits<char>, std::allocator<char> >,² so a function like
void FillLookupTable(std::map<std::string, std::string>& table);
formally has the signature (deep breath)
FillLookupTable> > > > >&):
Good luck typing that into a debugger.
¹ The fact that they remain in the original namespace has consequences for argument-dependent lookup:
namespace X { struct S {}; void fiddle(S const&); } namespace Y { using namespace X; void fiddle(S const&); } void test() { Y::S s; fiddle(s); // X::fiddle, not Y::fiddle }
² What you’re seeing is a combination of the type alias and the template default parameters.
It’s somewhat confusing when you refer to types as “objects”. At least in C++, “object” is a term of art, and types are not objects. You might have meant “entity”; types are entities (and so are objects), while type aliases are not.
I concur. At least in .NET, System.Console is a class, not object.
Excellent point. Will fix.
The alias in C# works somehow differently with C++. For example,
You can’t refer it as
in C# always imports names into the “un-namespaced” scope.
And also, it only import top level things, not nested namespaces. With
, you still can’t refer
as
The differences between the two languages can be an interesting topic.
in C++ powers templates by associating two types together. | https://devblogs.microsoft.com/oldnewthing/20220117-00/?p=106167 | CC-MAIN-2022-21 | refinedweb | 661 | 50.87 |
I'll one up y'all: public class Sneak { public static RuntimeException sneakyThrow(Throwable t) { if ( t == null ) throw new NullPointerException("t"); Sneak.<RuntimeException>sneakyThrow0(t); return null; }
Advertising
@SuppressWarnings("unchecked") private static <T extends Throwable> void sneakyThrow0(Throwable t) throws T { throw (T)t; } There is absolutely no point in wrapping everything into a gazillion layers of exceptions - that just results in 10 pages of stacktrace to walk through. Preferably, all your classes throw the exceptions they cause, but if interface restrictions are preventing you from sticking 'throws SQLException' in the appropriate places, use this. Don't wrap unless there's a good reason for it. A good reason would be if e.g. a database abstraction layer has its own 'DataSourceException', and a specific implementation that works with files wraps FileNotFoundExceptions in DataSourceExceptions. That's useful wrapping. turning everything into 'MyRuntimeException' is a waste of time. Or, of course, use project lombok and add "@SneakyThrows (SQLException.class)" to your method, which saves you a try/catch block. On Aug 15, 5:22 pm, Fabrizio Giudici <fabrizio.giud...@tidalwave.it> wrote: > Casper Bang wrote: > > Hehe that's a big can of worms to open up in here, but I do the same. > > I too have some rough code that does exception handling for > transactions, to decide whether to retry or abort. > > -- > Fabrizio Giudici - Java Architect, Project Manager > Tidalwave s.a.s. - "We make Java work. Everywhere." > weblogs.java.net/blog/fabriziogiudici - > fabrizio.giud...@tidalwave.it - mobile: +39 348.150.6941 --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "The Java Posse" group. To post to this group, send email to javaposse@googlegroups.com To unsubscribe from this group, send email to javaposse+unsubscr...@googlegroups.com For more options, visit this group at -~----------~----~----~----~------~----~------~--~--- | http://www.mail-archive.com/javaposse@googlegroups.com/msg05984.html | CC-MAIN-2017-22 | refinedweb | 297 | 58.28 |
Asynchronous Web Services for Visual Basic .NET
Asynchronous Web Services rely on the basic asynchronous behavior built into .NET; it is part of the multithreading model of .NET. The basic idea is that you can invoke a Web Method asynchronously, which means it returns before it has finished the computation, and the Web Service will tell you at a later time when it has finished. Collectively, all of this technology relies on the CodeDOM, multithreading, SOAP, HTTP, and delegates, which illustrates why a well-architected platform is essential. Fortunately, .NET is designed so that you don't really have to master any of these technologies to use asynchronous Web Services. The hardest thing you have to learn to do is to use delegates.
When you are finished reading this article you will have the basic information necessary to invoke Web Methods asynchronously. We'll use a basic Web Service that returns simple data, pretending the process is long enough to warrant an asynchronous call. In July 19th's article, I wrote about calculating prime numbers. I will use a Web Service based on the ability to calculate prime numbers, returning a Boolean to indicate prime-ness.
Integrating a Web Service into Your Application
- Create the solution for you client application
- Use UDDI to find a Web Service (or you can use a known Web Service)
- Select Project|Add Web Reference, entering the URL for the Web Service in the Address bar. (This process is just like browsing in internet explorer)
- When you have navigated to the URL of the Web Service, the Add Web Reference button should be enabled in the Add Reference dialog. Click Add Reference
After you have selected the .asmx file representing the Web Service and added the reference, a new entry will be added to your project in the Web References folder. The folder name will be Web References (see figure 1) and a namespace, representing the Web Service host will be added to that namespace. There will be three files with the extensions .map, .disco, and .wsdl. Collectively, this information points at our Web Service.
There is one other file that was added to the Web References folder that doesn't show up in the Server Explorer, Reference.vb. Reference.vb contains a proxy class that inherits from System.Web.Services.Protocols.SoapHttpClientProtocol; this class is a proxy-or wrapper-for the Web Service. The proxy class is generated using the .NET CodeDOM technology and is responsible for marshalling calls between your application and the Web Service, making Web Services easier to use.
Tip: To obtain a Web Service description you can type the URL followed by the query WSDL. For example, on my machine I can obtain a Web Service description of the Primes service by typing in the Address bar of Internet Explorer.
Importantly, the proxy class contains three methods for every Web Method. One is a proxy for the synchronous version of the Web Method, and the other two are proxy methods for the SoapHttpClientProtocol.BeginInvoke and SoapHttpClientProtocol.EndInvoke. That is, the second pair of methods represents proxies for asynchronous invocation of the Web Service.
Invoking a Web Method Asynchronously
We can figure out how to invoke the Web Service asynchronously by examining the proxy methods. Listing 1 shows the proxy methods for the Web Method IsPrime.
Listing 1: Asynchronous proxy methods for the Web Method IsPrime.
Public Function BeginIsPrime(ByVal number As Long, _ ByVal callback As System.AsyncCallback, _ ByVal asyncState As Object) As System.IAsyncResult Return Me.BeginInvoke("IsPrime", New Object() {number}, _ callback, asyncState) End Function Public Function EndIsPrime( _ ByVal asyncResult As System.IAsyncResult) As Boolean Dim results() As Object = Me.EndInvoke(asyncResult) Return CType(results(0),Boolean) End Function
As the name suggests we call BeginIsPrime to initiate the asynchronous call. The proxy for BeginInvoke is a function that returns an interface IAsyncResult. The return value is used to synchronize interaction between the client and the Web Service. The first parameter is the value we pass to the Web Service; in this instance it is the number that we want to check for prime-ness. The second parameter is the callback. The second parameter will be the address of the method we want the Web Service to invoke when the Web Method has finished processing. The type of the callback method is the delegate AsyncCallback. The third argument is any additional object we want to pass through to the Web Service and the callback method. The third parameter can be used for any additional information, including simple data or objects.
The second method is called when the Web Service is ready or to block in the client until the Web Service is ready. For example, you can call the EndInvoke proxy in the callback method when the Web Service calls it. The callback is defined such that it accepts, and will receive, an IAsyncResult argument that you pass back to the EndInvoke proxy. The IAsyncResult object is used to synchronize the data exchange between the client and Web Service.
Listing 2 provides a slim example that combines all of the elements together. After the listing is an overview of the code as I wrote it.
Listing 2: Invoking a Web Method asynchronously.
1: Imports System.Console 2: Imports System.Threading 3: 4: Public Class Form1 5: Inherits System.Windows.Forms.Form 6: 7: [ Windows Form Designer generated code ] 8: 9: Private Sub Button1_Click(ByVal sender As System.Object, _ 10: ByVal e As System.EventArgs) Handles Button1.Click 11: 12: ListBox1.Items.Clear() 13: Start() 14: End Sub 15: 16: Private Service As localhost.Service1 = _ 17: New localhost.Service1() 18: Private Sub Start() 19: 20: Dim Numbers() As Long = _ 21: New Long() {103323, 2, 3, 56771, 7} 22: Dim Number As Long 23: 24: For Each Number In Numbers 25: Dim Result As IAsyncResult = _ 26: Service.BeginIsPrime(Number, _ 27: AddressOf Responder, Number) 28: Next 29: 30: End Sub 31: 32: Private Sub Responder(ByVal Result As IAsyncResult) 33: 34: Dim IsPrime As Boolean = Service.EndIsPrime(Result) 35: 36: If (InvokeRequired) Then 37: Invoke(New MyDelegate(AddressOf AddToList), _ 38: New Object() {IsPrime, _ 39: CType(Result.AsyncState, Long)}) 40: End If 41: 42: End Sub 43: 44: Private Delegate Sub MyDelegate( _ 45: ByVal IsPrime As Boolean, ByVal Number As Long) 46: 47: Private Sub AddToList(_ 48: ByVal IsPrime As Boolean, ByVal Number As Long) 49: 50: Const Mask As String = _ 51: "{0} {1} a prime number" 52: 53: Dim Filler() As String = New String() {"is not", "is"} 54: ListBox1.Items.Add( _ 55: String.Format(Mask, Number, _ 56: Filler(Convert.ToInt16(IsPrime)))) 57: 58: End Sub 59: 60: End Class
(The code generated by the designer is condensed-simulating Code Outlining in Visual Studio .NET-on line 7.) The basic idea is that the consumer sends several inquiries about possible prime numbers. Large prime numbers take longer to calculate than prime numbers; so the client application is designed to send every number asynchronously rather than get bogged down on big prime candidates.
The process is initiated in the Button1_Click event on line 13 when Start is invoked. (The actual application sends the same numbers ever time, but you could easily make this dynamic, too.)
Start is defined on lines 18 through 30 in listing 1. An array of candidate numbers is created on lines 20 and 21, demonstrating inline initialization in Visual Basic .NET. As you can see the largest number is first. In a synchronous application the remaining numbers would wait in line until 103323 was evaluated. In our model all requests will be sent and the results displayed as they are available. The For Each loop manages sending every number to be processed, representing ongoing work while preceding requests are being serviced by the Web Service.
The code we are interested in is on lines 25 through 27. Line 25 shows you how to obtain an IAsyncResult object in case we elect to block in the Start method. (We won't.) The first argument is the Number to be evaluated by the Web Method IsPrime; the second argument is the delegate, created implicitly with the AddressOf operator, and the third argument is the Number. I passed the Number a second time for display purposes (refer to line 55). The Web Service was created on lines 16 and 17, before the Form's constructor was called. The name localhost represents a namespace in this context and happens to be derived from the Web Service host computer.
Retrieving the Results from the Web Method
There are several ways to block while you are waiting for a Web Service to return. You can use the IAsyncResult.IsCompleted property in a loop, call Service.EndIsPrime-the EndInvoke proxy-or request theIAsyncResult.AsyncWaitHandle. In our example, we process merrily until the callback is invoked by the Web Service. The callback method is defined on lines 32 through 42. When the callback is called we can obtain the result by calling the EndInvoke proxy method as demonstrated on line 34.
Lines 36 through 40 and 44 through 58 exist in this instance due to the kind of application—a Windows Form application. When you invoke a Web Service asynchronously the callback method will be called back on a different thread than the one the Windows Forms controls reside on. As Windows Forms is not thread-safe-which means you should interact with Windows Forms controls on the same thread as the one they live on-we can use the Control.Invoke method and push the "work" onto the same thread that the control lives on. Again we use delegates to represent the work to be done.
The method InvokeRequired can be used to determine if you need to call invoke, as demonstrated on line 36. Lines 37, 38, and 39 demonstrate the Invoke method. Define a new delegate based on the signature of the procedure you want to Invoke. Create an instance of that delegate type, initializing the delegate with the address of your work procedure. Pass an array of objects matching the parameters your work-method needs. The delegate is defined on lines 44 and 45. An instance of the delegate is created on line 37, and the array of arguments is demonstrated on lines 38 and 39. Lines 38 and 39 create an array of Object inline passing a Boolean and a Long as is expected by the AddToList method. Pay attention to the fact that the delegate signature, the procedure used to initialize the delegate, and the arguments passed to the delegate all of have identical footprints.
Summary
Asynchronous Web Services depend on a lot of advanced aspects of the .NET framework, including SOAP, XML, HTTP, CodeDOM, TCP/IP, WDSL, UDDI, multithreading, and delegates, to name a view. Fortunately, these technologies exist already and work on our behalf behind the scenes for the most part. If you want to use asynchronous Web Services, the hardest thing you need to master are delegates.
Don't let anyone trivialize Web Services. They are powerful and complicated, but the complicated part was codified by Microsoft. The end result is that Web Services are easy to consume, with only modest additional complexity to invoke them asynchronously.
Asynchronous Web Services will add some zip to your applications. Be mindful of the existence of more than one thread and you are all set..
There are no comments yet. Be the first to comment! | http://www.codeguru.com/columns/vb/article.php/c6539/Asynchronous-Web-Services-for-Visual-Basic-NET.htm | CC-MAIN-2015-18 | refinedweb | 1,918 | 55.64 |
Mat and I were scanning through github one day and a pretty lengthy, complex piece of code caught our eye (Caution: Do not read if you’re prone to seizures or have a heart condition). This code is one of the many intricacies involved in mono’s bytecode interpreter, and it was beautiful, at least to us. Why must it be so complex? How hard can it be? After a lengthy discussion, we decided the best thing to do at this point was have a competition to see which one of us can write the fastest VM bytecode interpreter in two hours. A few insults later (“Your mother’s filesystem is so fat etc.”), we decided to set a few ground rules and agree on a benchmark.
I came up with a pretty simple piece of code that contains addition, multiplication, and conditional branches. I then generated a generic bytecode equivalent of the benchmark to be used in our interpreter.
As a control, the C benchmark runs on the native machine at an average time of 0.233 secs. In my first attempt, I wrote a simple C program that reads each instruction and jumps to a corresponding block of code.
... int vm(inst *i) { static void *optable[]={ [OP_NOP] = &&op_nop, [OP_LDI] = &&op_ldi, [OP_LDR] = &&op_ldr, [OP_STO] = &&op_sto, [OP_ADD] = &&op_add, [OP_SUB] = &&op_sub, [OP_MUL] = &&op_mul, [OP_DIV] = &&op_div, [OP_MOD] = &&op_mod, [OP_ORR] = &&op_orr, [OP_XOR] = &&op_xor, [OP_AND] = &&op_and, [OP_SHL] = &&op_shl, [OP_SHR] = &&op_shr, [OP_NOT] = &&op_not, [OP_NEG] = &&op_neg, [OP_CMP] = &&op_cmp, [OP_BEQ] = &&op_beq, [OP_BNE] = &&op_bne, [OP_BGT] = &&op_bgt, [OP_BLT] = &&op_blt, [OP_BGE] = &&op_bge, [OP_BLE] = &&op_ble, [OP_CAL] = &&op_cal, [OP_JMP] = &&op_jmp, [OP_RET] = &&op_ret, [OP_EOF] = &&op_eof }; int r[4], s[32], *sp = s; inst *ip = i; ... op_nop: goto *(++ip)->jmp; op_ldi: *sp++ = ip->arg; goto *(++ip)->jmp; op_ldr: *sp++ = r[ip->arg]; goto *(++ip)->jmp; op_sto: r[ip->arg] = *--sp; goto *(++ip)->jmp; op_add: sp--, sp[-1] += *sp; goto *(++ip)->jmp; op_sub: sp--, sp[-1] -= *sp; goto *(++ip)->jmp; op_mul: sp--, sp[-1] *= *sp; goto *(++ip)->jmp; ... }
This works by creating an array of goto pointers (I believe this is a gcc extension), a pseudo-stack, and a list of registers, then jumping to each instruction while increasing the instruction pointer. This simple virtual machine executed the bytecode in 6.421 secs, which was way too slow for my taste, so I had to figure out another approach.
Why don’t I just compile the bytecode into x86 machine code, like modern JIT VMs? That could easily be my ticket to victory. I had about an hour left in the competition so I made haste. I began to replace the optable full of goto addresses into x86 instructions, then allocated some executable memory, copied the instructions, and jumped to it.
... int vm(inst *i) { struct { int32_t size, arg, jmp; char data[16]; } *op, optable[]={ INS(op_nop, 0, 0, 0, 0x90), INS(op_ldi, 4, 1, 0, 0x68), INS(op_ld0, 0, 0, 0, 0x53), ... INS(op_add, 0, 0, 0, 0x58, LONG 0x01, 0x04, 0x24), INS(op_sub, 0, 0, 0, 0x58, LONG 0x29, 0x04, 0x24), INS(op_mul, 0, 0, 0, 0x5a, LONG 0x8b, 0x04, 0x24, LONG 0x0f, 0xaf, 0xc2, LONG 0x89, 0x04, 0x24), ... INS(op_ble, 4, 0, 2, 0x0f, 0x8e), INS(op_cal, 4, 0, 1, 0xe8), INS(op_jmp, 4, 0, 1, 0xe9), INS(op_ret, 0, 0, 0, 0xc3), ... }; ... if (!(pn = mmap(0, m, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANON, -1, 0))) return 0; ... ((void(*)()) pn)(); printf("%d\n", r0); return 0; }
On runtime this created a small, 122 byte x86 program based upon the benchmark bytecode which clocked in at an average speed of 0.518 secs. This was only around twice as slow as the control so I was fairly confident at this point.
I slickly inquired into what Mat was working on, and he informed me he was writing his bytecode interpreter in Visual Basic.NET. I was a bit skeptical at first, considering he did not know Visual Basic, but was reassured he wasn’t joking. Evidently he taught himself Visual Basic in the span of 2 hours to what amounts to be the ultimate coding troll. He’s not one to lose these competitions, so I assumed he has some trick up his sleeve. He submitted his code for approval:
... For ip = 0 to ops.Length - 1 Dim i as VMI = ops(ip) il.MarkLabel(jmp(ip)) Select Case i.Opcode Case "ldi" il.Emit(Opcodes.Ldc_i4, i.Operand) Case "ldr" il.Emit(Opcodes.Ldloc, i.Operand) Case "sto" il.Emit(Opcodes.Stloc, i.Operand) Case "jmp" il.Emit(Opcodes.Br_S, jmp(i.operand)) Case "mul" il.Emit(Opcodes.Mul) Case "add" il.Emit(Opcodes.Add) Case "eof" il.Emit(Opcodes.Ldloc, 0) il.Emit(Opcodes.Ret) Case "cmp" Select Case (ops(ip+1).opcode) Case "blt" il.Emit(Opcodes.Blt, jmp(ops(ip+1).operand)) Case Else Console.WriteLine("unsupported branch: {0}", ops(ip+1).opcode) End Select ip = ip + 1 Case Else Console.WriteLine("unsupported opcode: {0}", i.Opcode) End Select Next Console.WriteLine("{0}", _ CType(program.CreateDelegate(GetType(tmplP1(Of Long, Integer))), tmplP1(Of Long, Integer))(0)) ...
Once compiled, his code ran the benchmark at an average speed of 0.127 secs….. Wait, what?
# vbnc simvm.vb && time mono simvm.exe 857419840 real 0m0.127s user 0m0.120s sys 0m0.000s
I wouldn’t have believed it if I didn’t see it myself. My code generates native Assembly… Assembly! And his is written in Visual Basic. I’m sure there is some trickery going on, like mono optimizing the emitted instructions, but I haven’t as of yet ruled out witchcraft. I was forced to conclude that Visual Basic is faster than Assembly, that I’m a horrible coder, and Mat wins.
UPDATE: Its been mentioned that I didn’t compile the control with optimization on. I turned optimization off because gcc is way too damn smart. It almost literally translated the code into ‘printf(“857419840\n”);’. I think a better example would be if we didn’t give gcc the answer on compile-time, since none of the VM’s were given that opportunity until it read the instructions on run-time. The VM’s did not, and could not know ahead of time the loop amount, or even the general flow of the bytecode for that matter. So by saving the loop amount in a variable declared as volatile, you prevent gcc from optimizing it out:
#include <stdio.h> int main(int argc, char **argv) { volatile int k = 10000; int s, i, j; for (s = 0, i = 0; i < k; i++) { for (j = 0; j < k; j++) s += i * j; } printf("%d\n", s); return 0; }
That code compiled with -O3 runs at 0.085 sec on my machine. Surprisingly its only 66% faster then the Visual Basic example.
{ 24 comments }
Nerds…………………… ..
Doesn’t there exist a loop-unroll optimizer for Mono bytecode interpreter? I’d expect Ben’s C/x86 ASM VM to run in same amount of time if the nested loops are submitted as a single loop. BTW, such a nerdy friendship! Cograts!
“You’re mother’s …” = “You are mother’s …”
WTF does that mean?
You mean “Your mother’s …”, right?
Fixed a typo, thank you.
I liked this post. I am interested in making/seeing a comparison to the LLVM JIT. I am not sure about .NET, but LLVM does not have partial unrolling and vectorization, so its hard for me to estimate who might win this.
Visual Basic is faster than Assembly
It’s Mono’s loop-unroll optimizer like Volkan YAZICI said:) To be fair add -O3 to gcc to get optimized machine code timings and then compare! Who’s faster now?
$ time ./o0
857419840
real 0m0.289s
user 0m0.284s
sys 0m0.008s
$ time ./o3
857419840
real 0m0.002s
user 0m0.000s
sys 0m0.000s
You really should’ve mentioned the control program is unoptimized, as now it will distract from an actually useful point: being able to translate programs in arbitrary languages into bytecode for a heavily optimized platform is a huge boon to anyone writing a language implementation.
This is why you see all these language implementations popping up on the JVM (and to a lesser extent the CLR): It has a fairly robust instruction set, and you get to leverage all that work Sun put in to make the JVM fast. Your friend’s interpreter is a good example of the above point.
BORING………………………………….
First: It does raise a question of what is the minimum set of opcodes necessary? So, the JVM has a ton of opcodes, as does Parrot, etc., but could any of those be considered fluff?
Second: I may be completely off-base here, but isn’t most of the runtime of a VM taken up with I/O and translation to opcodes?
I am, admittedly, a VM-gizzards noob.
The minimum? One.
I suppose you can implement a RISC VM, but the more instructions the better. There is little to no penalty in speed for increased instruction sets.
I had thought at one point the time it took for JIT to process would hinder the speed of the application. Yet, the speed improvement seems to outweigh the overhead.
“There is little to no penalty in speed for increased instruction sets.”
Well, actually there is. Once the hot code of your VM interpreter blows the physical CPU’s instruction cache, you’ll encounter a _severe_ performance hit.
You can get away with just a single (complex) opcode and still be turing complete. It’s called OISC.
What did you compile the C program with? Gcc? Icc? Llvm? Which level of optimization? One thing beating the unoptimized C, another a highly optimized one:)
Added:
Imports System.Diagnostics
…
dim sw as new Stopwatch
sw.start
…
sw.stop
Console.WriteLine(“Elapsed: {0}”,sw.Elapsed)
Console.WriteLine(“In milliseconds: {0}”,sw.ElapsedMilliseconds)
Console.WriteLine(“In timer ticks: {0}”,sw.ElapsedTicks)
and got:
c:\temp>vbc /optimize simVB.vb
Microsoft (R) Visual Basic Compiler version 10.0.30319.1
c:\temp>simVB.exe
857419840
Elapsed: 00:00:00.0763237
In milliseconds: 76
In timer ticks: 198265
Unless I’m reading that wrong…that’s faster than -O3
Been a while since I’ve used mono – but I’m pretty sure it has /optimize…
Actually fascinating. Most of us wish we had a bud like Mat to challenge us!
This is the greatest blog post of all time.
Of course it does. JIT compilation is not a 0-time expenditure. However, if you make a very slight change (already rocking that the change is so slight) and export a .exe file…then compare that to optimized C. It’ll be fairly close, maybe 2x (optimized C vs optimized .NET plus overhead). Both will end up running a “save then print a precompiled constant”, of course.
That you can get .NET optimization so free is something pretty awesome. I didn’t see in the article anything showing which optimization options were used, though I did see that none were in comments, and my other comments here reflect that.
Of course 100% optimized C code will outrun any VM. Can OP give us a fully optimized control for reference, anyway? On the box that ran the other tests?
E: And about your edit…I THOUGHT so. I had trouble finding anything for sure, but I was pretty damn sure we could unroll the loop when the Delegate compiled.
Technically, when you turn source code into a parse tree (or other internal representation) it’s no longer a pure interpreter.
If that’s too technical, how about this: Compiling to bytecode is still compiling, because the only difference between bytecode and machine code is whether there is a (possibly microcoded) hardware implementation.
In simvm-slow.c, what’s the rationale for using:
#define NEXT() __asm__(“jmp *%0″::”r”((++ip)->jmp)); goto *ip->jmp
instead of
#define NEXT() goto *(++ip)->jmp
?
love that assumption “world is 99% built on x86″, caused mainly by illiteracy about any other platforms or refuse to admit that all their *elegance* will go down pipes once assumption is removed… :)))
I got bored and decided to see if, by your logic, C was faster than Assembly too!
Here is my implementation of your VM.
Basically, it build a C file, calls gcc, and runs the executable.
$ time ./bench # original benchmark code
857419840
real 0m0.396s
user 0m0.390s
sys 0m0.003s
$ time ./simvm # your asm version
857419840
real 0m0.759s
user 0m0.760s
sys 0m0.000s
$ time ./rofl_vm # my version
857419840
real 0m0.208s
user 0m0.143s
sys 0m0.033s
C IS FASTER THAN ASSEMBLY!
Note: simvm and simvm were built using -O4 and bench was built with -O0
I would have tested the VB version but mono kept crashing on CreateDelegate.
P.S. I agree with your point, I just wanted to post that for comedic effect.
I’ve written a similar thing, but the opcode generation was more generic using an assembler. Nice source anyway.
hahaha, interesting article | http://byteworm.com/2010/11/21/the-fastest-vm-bytecode-interpreter/ | CC-MAIN-2016-07 | refinedweb | 2,160 | 75.61 |
can somebody tell me how to create stack array in easy way and can make me and others like me easy to understand? tell me how to create stack array in easy way and can make me and others like me easy to understand? please
anyway, im doin some home that my lecturer gave to me, so here what i done so far...
import java.util.*; public class Usestack { public static void main(String args[]){ Scanner sc; sc=new Scanner (System.in); int n; System.out.println("enter the size of stack"); n=sc.nextInt(); Stack s=new Stack(); int choice; do{ System.out.print("1. push, 2. pop, 3. display, 0. exit, enter your choice: "); choice=sc.nextInt(); switch(choice){ case 1: int value; System.out.print("enter element to push: "); value=sc.nextInt(); s.push(value); break; case 2: s.pop(); break; case 3: System.out.println(s); break; case 0: break; default:System.out.println("invalid choice"); } }while(choice!=0); } }
when i click run the program, it can be 'use', but... my lecturer said that my ARRAY size no function, that true, when i run the program the first line said "enter the size of stack", so i enter 2 or 3 size of stack, but then, the program show that i can push many element as i want, more than what i enter the size of stack, so how to do the stack size(to input)...
The Java stack class extends the Vector super class, so it will automatically expand itself when you try to add elements beyond the current size.The Java stack class extends the Vector super class, so it will automatically expand itself when you try to add elements beyond the current size.
If you really want to limit the stack size, you need to check the size in case 1 before allowing the user to push more onto the stack:
case 1: if (s.size() < n) { // code to add new element to stack } else { System.out.println("You've reached the stack limit!"); } break; | http://www.javaprogrammingforums.com/collections-generics/2274-stack-array.html | CC-MAIN-2014-35 | refinedweb | 342 | 73.78 |
Enable Access-Based Enumeration on a Namespace
Published: June 3, 2009
Applies To: Windows Server 2008
Access-based enumeration hides files and folders that users do not have permission to access. By default, this feature is not enabled for DFS namespaces. You can enable access-based enumeration of DFS folders by using the Dfsutil command, enabling you to hide DFS folders from groups or users that you specify. To control access-based enumeration of files and folders in folder targets, you must enable access-based enumeration on each shared folder by using Share and Storage Management.
To enable access-based enumeration on a namespace, all namespace servers must be running at least Windows Server 2008..
To enable access-based enumeration on a namespace by using Windows Server 2008, you must use the Dfsutil command. To use DFS Management or Dfsutil to perform this procedure on a server running Windows Server® 2008 R2, see Enable Access-Based Enumeration on a Namespace ()..
To limit which groups or users can view a DFS folder, you must use the Dfsutil command to set explicit permissions on each DFS folder.
Open an elevated | http://technet.microsoft.com/en-us/library/dd919212.aspx | CC-MAIN-2014-52 | refinedweb | 188 | 51.18 |
- Author:
- hdknr
- Posted:
- April 17, 2010
- Language:
- Python
- Version:
- 1.1
- utf8 katakana
- Score:
- 1 (after 1 ratings)
Katakana in UTF-8 check
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import unicodedata def is_katakana(unichr): unichr = unicodedata.normalize('NFC', unichr) for c in unichr: if not unicodedata.name(c).startswith('KATAKANA'): return False return True</pre>
#
Please login first before commenting. | https://djangosnippets.org/snippets/1991/ | CC-MAIN-2016-36 | refinedweb | 116 | 58.82 |
...one of the most highly
regarded and expertly designed C++ library projects in the
world. — Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
extract_c_string returns
a pointer to an array of elements of a const character type. It is invoked
through a static method
call.
This customization point is responsible for handling it's own garbage
collecting; the lifetime of the returned C-string must be no shorter
than the lifetime of the string instance passed to the
call method.
#include <boost/spirit/home/support/string_traits.hpp>
Also, see Include Structure.
template <typename String> struct extract_c_string { typedef <unspecified> char_type; static char_type const* call (String const&); };
Notation
T
An arbitrary type.
Char
A character type.
Traits
A character traits type.
Allocator
A standard allocator type.
str
A string instance.
This customization point needs to be implemented whenever
traits::is_string is implemented.
If this customization point is implemented, the following other customization points need to be implemented as well. | https://www.boost.org/doc/libs/1_64_0/libs/spirit/doc/html/spirit/advanced/customize/string_traits/extract_c_string.html | CC-MAIN-2021-49 | refinedweb | 157 | 50.43 |
On Mon, Apr 08, 2002 at 06:35:58PM +0100, Paul Sargent wrote: > I'm getting quite a lot of messages dropping through my procmail rules for > debian lists. I was wondering if anyone here had a good setup. > > The problem seems to be that not all mails from this list get tagged with > X-Mailing-List which is what I'm checking on. > > This is my current rule: > > :0: > * ^X-Mailing-List: <debian-.+@lists.debian.org> > * ^X-Mailing-List: <debian-\/[^@]+ > $DEBIAN/$MATCH I use exim's filtering capability instead of procmail (and I dump all my debian lists into a single mailbox), but if $h_X-Mailing-List: contains "ebian-" then save $home/Mail/deb endif seems to work pretty well for me. I'll have one message slip by every couple months or so, but not enough to be a bother. Maybe you just need to modify the regexes you're matching against X-Mailing-List to be a little less demanding, although I would expect that header to be set identically on every message... -- | https://lists.debian.org/debian-user/2002/04/msg01314.html | CC-MAIN-2017-17 | refinedweb | 176 | 66.17 |
This is a function that does some currying:
add = (a,b) -> if not b? return (c) -> c + a a + b
JavaScript provides the capability to reflect on the number of arguments:
add.length
and to determine how many arguments were provided:
add = (a,b) -> if arguments.length < add.length return (c) -> c + a a + b
so it seems like it should be possible to write a function that magically returns a function that requires the right number of arguments. So I could have a function:
f = (a,b,c,d,e,f) -> ..
if invoked with:
f(1,2)
it should return:
(c,d,e,f) ->
anyone know how to do that?
Update
Lots of good comments on the original gist | https://www.withouttheloop.com/articles/2012-02-18-currying/ | CC-MAIN-2022-27 | refinedweb | 120 | 73.17 |
#include <deal.II/lac/matrix_out.h>
Output a matrix in graphical form using the generic format independent output routines of the base class. The matrix is converted into a list of patches on a 2d domain where the height is given by the elements of the matrix. The functions of the base class can then write this "mountain representation" of the matrix in a variety of graphical output formats. The coordinates of the matrix output are that the columns run with increasing x-axis, as usual, starting from zero, while the rows run into the negative y-axis, also starting from zero. Note that due to some internal restrictions, this class can only output one matrix at a time, i.e. it can not take advantage of the multiple dataset capabilities of the base class.
A typical usage of this class would be as follows:
Of course, you can as well choose a different graphical output format. Also, this class supports any matrix, not only of type FullMatrix, as long as it satisfies a number of requirements, stated with the member functions of this class.
The generation of patches through the build_patches() function can be modified by giving it an object holding certain flags. See the documentation of the members of the Options class for a description of these flags.
Definition at line 69 of file matrix_out.h.
Declare type for container size.
Definition at line 75 of file matrix_out.h.
Abbreviate the somewhat lengthy name for the DataOutBase::Patch class.
Definition at line 147 of file matrix_out.h.
Destructor. Declared in order to make it virtual.
Definition at line 32 of file matrix_out.cc.
Generate a list of patches from the given matrix and use the given string as the name of the data set upon writing to a file. Once patches have been built, you can use the functions of the base class to write the data into a files, using one of the supported output formats.
You may give a structure holding various options. See the description of the fields of this structure for more information.
Note that this function requires that we can extract elements of the matrix, which is done using the get_element() function declared in an internal namespace. By adding specializations, you can extend this class to other matrix classes which are not presently supported. Furthermore, we need to be able to extract the size of the matrix, for which we assume that the matrix type offers member functions
m() and
n(), which return the number of rows and columns, respectively.
Definition at line 317 of file matrix_out.h.
Function by which the base class's functions get to know what patches they shall write to a file.
Implements DataOutInterface< 2, 2 >.
Definition at line 38 of file matrix_out.cc.
Virtual function through which the names of data sets are obtained by the output functions of the base class.
Implements DataOutInterface< 2, 2 >.
Definition at line 46 of file matrix_out.cc.
Get the value of the matrix at gridpoint
(i,j). Depending on the given flags, this can mean different things, for example if only absolute values shall be shown then the absolute value of the matrix entry is taken. If the block size is larger than one, then an average of several matrix entries is taken.
Definition at line 279 of file matrix_out.h.
This is a list of patches that is created each time build_patches() is called. These patches are used in the output routines of the base classes.
Definition at line 154 of file matrix_out.h.
Name of the matrix to be written.
Definition at line 159 of file matrix_out.h. | http://www.dealii.org/developer/doxygen/deal.II/classMatrixOut.html | CC-MAIN-2015-48 | refinedweb | 610 | 64.91 |
I've finally got it! Thanks for the help you posted on your scratchpad. After a few hours of study, it finally paid off. I've commented it to describe how it works, and made a few changes to fix a minor bug, and remove some code that is never executed, and removed a state variable:
#------------------------------------------------------------
# Return an iterator of all possible combinations (of all
# lengths) of a set of symbols with the constraint that each
# symbol in each result is less than the symbol to its right.
#
sub combo {
# The symbols we draw our results from:
my @list = @_;
# The trivial case
return sub { ( ) } if ! @_;
# Persistent state for the closure
my (@position, # Last set of symbol indices generated
@stop); # Last set possible for $by symbols
# Start by telling iterator that it just finished
# (next=1) all results of 0 digits.
my ($by, $next) = (0, 1);
return sub {
[download]
# We're done after we've returned a list of all symbols
return () if @position == @list;
[download]
if ( $next ) {
# We finished all combos of size $by, now do $by+1
$by++;
[download]
# If new size is larger than list, we're done!
return () if $by > @list;
[download]
# Start with leftmost $by symbols (except last,
# which is preincremented before use)
@position = (0 .. $by - 2, $by - 2);
# Our stop condition is when we've returned the
# rightmost $by symbols
@stop = @list - $by .. $#list;
$next = undef;
}
# Start by trying to advance the rightmost digit
my $cur = $#position;
{ # **** redo comes back here! ****
# Advance current digit to next symbol
if ( ++$position[ $cur ] > $stop[ $cur ] ) {
# Keep trying next-most rightmost digit
# until we find one that's not 'stopped'
$position[ --$cur ]++;
redo if $position[ $cur ] > $stop[ $cur ];
# Reset digits to right of current digit to
# the leftmost possible positions
my $new_pos = $position[ $cur ];
@position[$cur .. $#position] = $new_pos .. $new_pos+$
+by;
}
}
# Advance to next result size when we return last
# possible result of this size
$next = $position[0]==$stop[0];
return @list[ @position ];
}
}
[download]
UPDATE: I just tweaked the code a bit to make it check for done less frequently so it'll run a bit quicker. It munges up the code listing a bit though. Is there a better way to edit the code so it's obvious without interspersing download links?
--roboticus
In reply to Re^3: Finding all Combinations
by roboticus
in thread Finding all Combinations
by n. | http://www.perlmonks.org/index.pl?parent=557196;node_id=3333 | CC-MAIN-2017-17 | refinedweb | 393 | 62.92 |
Forum Index
I don't know if this is the correct forum to report this. It didn't seam to fit in Learn and General and it's clearly dmd specific.
In my evaluation of a flyweight pattern by using const objects, I looked at the assembly code generated by dmd when using the 'is' operator with object references and Rebindable references which wraps the object reference in a struct.
The test code is as trivial as it could be so that the optimizer can't eliminate the code:
----
import std.stdio;
import std.typecons;
class Test
{
this(string s) { s_ = s; }
private string s_;
string toString() { return s_; }
}
void main(string[] args)
{
const Test t1 = new Test(args[0]), t2 = new Test(args[1]);
bool res1 = t1 is t2; // (1)
Rebindable!(const Test) rt1 = t1, rt2 = t2; // (2)
bool res2 = rt1 is rt2;
Rebindable!(const Test) rt3 = Rebindable!(const Test)(t1),
rt4 = Rebindable!(const Test)(t2); // (3)
bool res3 = rt3 is rt4;
writeln(res1, res2, res3);
}
----
I compiled with dub build -b release. Looking at the assembly with objdump on unix (gas assembly and not Intel assembly) I get the following
(1) object reference comparison
4394c6: 49 89 c4 mov %rax,%r12
4394c9: 4c 3b e3 cmp %rbx,%r12
4394cc: 0f 94 c0 sete %al
It can't be made more efficient than that. Perfect.
(2) Rebindable (struct) comparison
4394da: 48 8d 75 c8 lea -0x38(%rbp),%rsi
4394de: 48 8d 7d d0 lea -0x30(%rbp),%rdi
4394e2: b9 08 00 00 00 mov $0x8,%ecx
4394e7: 33 c0 xor %eax,%eax
4394e9: f3 a6 repz cmpsb %es:(%rdi),%ds:(%rsi)
4394eb: 74 05 je 4394f2 <_Dmain+0x82>
4394ed: 1b c0 sbb %eax,%eax
4394ef: 83 d8 ff sbb $0xffffffff,%eax
4394f2: f7 d8 neg %eax
4394f4: 19 c0 sbb %eax,%eax
4394f6: ff c0 inc %eax
It compares the struct as an 8 byte value (size of the object reference) with a byte per byte compare. After that it does some juggling with the result which I don't understand and doesn't seam necessary.
(3) Rebindable (struct) comparison
43950b: 48 8d 75 d8 lea -0x28(%rbp),%rsi
43950f: 48 8d 7d e0 lea -0x20(%rbp),%rdi
439513: b9 08 00 00 00 mov $0x8,%ecx
439518: 33 c0 xor %eax,%eax
43951a: f3 a6 repz cmpsb %es:(%rdi),%ds:(%rsi)
43951c: 40 0f 94 c7 sete %dil
Same as (2) but without any juggling with the boolean result.
It looks like struct comparison is not optimized when its size is a power of two. Since structs are often used as wrappers for "smart values", there is room for improvement here.
My conclusion is that when performance is important, avoid the use of structs for now.
The second conclusion is that Rebindable is currently not equivalent to a true mutable object reference in term of performance. But this is only a compiler issue for the moment and the reason I post this in this forum.
As I side note, I must admit that the optimizer works well. Most of my early test codes were optimized away. ;)
_______________________________________________
dmd-internals mailing list
dmd-internals@puremagic.com | https://forum.dlang.org/thread/doxujueniypgdsgebphv@forum.dlang.org | CC-MAIN-2021-39 | refinedweb | 527 | 66.37 |
Unless I'm completely missing your point, it looks like your sample strings do not contain the original phone numbers. The phone numbers are 10 digits, while the strings are 27. I'm going to assume that's a typo, and that the actual strings you're dealing with are concatenations of the three 10 digit numbers you listed, i.e.:
512567000151256700025125670003
512567000251256700015125670003
512567000351256700015125670002
If I'm misunderstanding you in some weird way, please let me know.
By "sameness check", I'm guessing you want a hashing function that will hash the above 3 30-character strings identically. That is, if the 10-digit numbers are $a, $b, and $c, the following 30-character strings should hash equivalently:
abc, acb, bac, bca, cab, cba
Finally, no other 30-character strings should hash to the same value.
If my interpretation of your requirements is correct, there's certainly more than one way to do it:
#!/usr/bin/env perl
use 5.014;
use warnings;
use Time::HiRes qw/time/;
use Benchmark qw/cmpthese timethese/;
use Inline 'C';
sub hash_pack($) { join '', sort unpack '(A10)*', shift }
sub hash_re($) { join '', sort $_[0] =~ /(\d{10})/g }
sub hash_substr($) {
my @nums; my $s = shift;
while ($s) {
push @nums, substr($s,0,10);
$s = substr($s,10);
}
join '',sort @nums;
}
# Only considers first 3 numbers
sub hash_substr2($) {
join '', sort substr($_[0],0,10),substr($_[0],10,10),substr($_[0],
+20,10);
}
my @funcs = map { "hash_$_" } qw/pack re substr substr2 c/;
my @strings = qw/512567000151256700025125670003
512567000251256700015125670003
512567000351256700015125670002/;
for my $s (@strings) {
printf "%12s(%s) => %s\n", $_, $s, eval "$_(\$s)" for @funcs;
}
my $s = $strings[0];
cmpthese timethese(-5, { map { $_ => "$_('$s')" } @funcs });
__END__
__C__
/* Try our own splitter sort. This swaps the numbers in-place
* as necessary to obtain a sorted order. */
#include <string.h>
#define SIZE 10
#define strswap(s1,s2,size) { \
int i; \
for (i = 0; i < size; i++) { \
s1[i] = s1[i] ^ s2[i]; \
s2[i] = s1[i] ^ s2[i]; \
s1[i] = s1[i] ^ s2[i]; \
} \
}
char * hash_c(char *str) {
char *n0 = str;
char *n1 = str + SIZE;
char *n2 = str + SIZE + SIZE;
if (strncmp(n0, n1, SIZE) > 0)
strswap(n0, n1, SIZE);
if (strncmp(n1, n2, SIZE) > 0)
strswap(n1, n2, SIZE);
if (strncmp(n0, n1, SIZE) > 0)
strswap(n0, n1, SIZE);
return str;
}
[download]
hash_pack(512567000151256700025125670003) => 5125670001512567000251
+25670003
hash_re(512567000151256700025125670003) => 5125670001512567000251
+25670003
hash_substr(512567000151256700025125670003) => 5125670001512567000251
+25670003
hash_substr2(512567000151256700025251256700015125670003) => 5125670001512567000251
+25670003
hash_re(512567000251256700015125670003) => 5125670001512567000251
+25670003
hash_substr(512567000251256700015125670003) => 5125670001512567000251
+25670003
hash_substr2(512567000251256700015351256700015125670002) => 5125670001512567000251
+25670003
hash_re(512567000351256700015125670002) => 5125670001512567000251
+25670003
hash_substr(512567000351256700015125670002) => 5125670001512567000251
+25670003
hash_substr2(512567000351256700015125670002) => 5125670001512567000251
+25670003
hash_c(512567000151256700025125670003) => 5125670001512567000251
+25670003
Benchmark: running hash_c, hash_pack, hash_re, hash_substr, hash_subst
+r2 for at least 5 CPU seconds...
hash_c: 6 wallclock secs ( 5.71 usr + 0.00 sys = 5.71 CPU) @ 46
+06276.36/s (n=26301838)
hash_pack: 6 wallclock secs ( 5.07 usr + 0.00 sys = 5.07 CPU) @ 64
+6938.07/s (n=3279976)
hash_re: 6 wallclock secs ( 5.03 usr + 0.00 sys = 5.03 CPU) @ 42
+2000.20/s (n=2122661)
hash_substr: 5 wallclock secs ( 5.04 usr + 0.00 sys = 5.04 CPU) @ 3
+28204.96/s (n=1654153)
hash_substr2: 4 wallclock secs ( 5.14 usr + 0.00 sys = 5.14 CPU) @
+965458.95/s (n=4962459)
Rate hash_substr hash_re hash_pack hash_substr2
+ hash_c
hash_substr 328205/s -- -22% -49% -66%
+ -93%
hash_re 422000/s 29% -- -35% -56%
+ -91%
hash_pack 646938/s 97% 53% -- -33%
+ -86%
hash_substr2 965459/s 194% 129% 49% --
+ -79%
hash_c 4606276/s 1303% 992% 612% 377%
+ --
[download]
You'll need to decide for yourself which is more appealing, and how much performance you'll need to squeeze out of this function. The C solution might be overkill, or the 3.77x speed gain compared to a pure Perl solution might be just what you need.
Input validation is left as an exercise to the reader.
In reply to Re: How to test for sameness on a string of numbers
by rjt
in thread How to test for sameness on a string of numbers
by willk | http://www.perlmonks.org/?parent=1024675;node_id=3333 | CC-MAIN-2015-48 | refinedweb | 671 | 81.22 |
This page describes how to resize an Anthos clusters on VMware (GKE on-prem) user cluster. Resizing a user cluster means adding or removing nodes. Adding nodes requires that IP addresses are available for the new nodes.
You resize a user cluster by changing the
replicas fields in the
nodePools
section of your cluster configuration file and then running
gkectl update cluster.
For information on maximum and minimum limits for user clusters, see Quotas and limits.
For information on managing node pools with
gkectl update cluster, see
creating and managing node pools.
Verify that enough IP addresses are available
If you intend to have N nodes after the resizing, then you must have N + 1 IP addresses available.
Verify that you have enough IP addresses. How you do the verification depends on whether the cluster uses a DHCP server or static IP addresses.
DHCP
If the cluster uses DHCP, check that the DHCP server can provide enough IP addresses. It must be able to provide at least one more IP address than the number of nodes that will be in the cluster after the resizing.
Static IPs
If the cluster uses static IPs, running
gkectl update cluster first verifies
whether you've allocated enough IP addresses in the cluster. If not, you can find
the number of extra IP addresses needed in the error message.
If you need to add more IP addresses to the user cluster, perform the following steps:
Open the user cluster's IP block file for editing.
Verify that all of the IP addresses you intend to use for the user cluster are included in the IP block file. The IP block file should have at least one more IP address than the number of nodes that will be in the cluster after the resizing.
To view the addresses reserved for a user cluster:
kubectl get cluster --kubeconfig ADMIN_CLUSTER_KUBECONFIG \ --namespace USER_CLUSTER_NAME USER_CLUSTER_NAME --output yaml
Replace the following:
ADMIN_CLUSTER_KUBECONFIG: the path of the admin cluster kubeconfig file
USER_CLUSTER_NAME: the name of the user cluster
Add as many additional static IP addresses to the corresponding block as required, and then run
gkectl update cluster.
Here is an example of an IP block file that has four IP addresses and the corresponding hostnames:
hostconfig: dns: 172.16.255.1 tod: 216.239.35.0 blocks: - netmask: 255.255.248.0 gateway: 21.0.135.254 ips: - ip: 21.0.133.41 hostname: user-node-1 - ip: 21.0.133.50 hostname: user-node-2 - ip: 21.0.133.56 hostname: user-node-3 - ip: 21.0.133.47 hostname: user-node-4
Resize the cluster
In the
user cluster configuration file,
update the value of the
replicas field in one or more of the
nodePools
elements.
Resize the cluster:
gkectl update cluster --kubeconfig ADMIN_CLUSTER_KUBECONFIG --config USER_CLUSTER_CONFIG
Replace the following:
ADMIN_CLUSTER_KUBECONFIG: the path of the admin cluster kubeconfig file
USER_CLUSTER_CONFIG: the path of the user cluster configuration file
Verify that the resizing succeeded:
kubectl --kubeconfig USER_CLUSTER_KUBECONFIG get nodes kubectl --kubeconfig USER_CLUSTER_KUBECONFIG describe machinedeployments NODE_POOL_NAME | grep Replicas
Replace the following:
USER_CLUSTER_KUBECONFIG: the path of the user cluster kubeconfig file
NODE_POOL_NAME: the name of the node pool that you resized.
Troubleshooting
See Troubleshooting cluster creation and upgrade. | https://cloud.google.com/anthos/clusters/docs/on-prem/1.9/how-to/resizing-a-user-cluster | CC-MAIN-2022-21 | refinedweb | 535 | 53.31 |
pip install adal
The Python adal library is among the top 100 Python libraries, with more than 21,606,771 downloads. This article will show you everything you need to get this installed in your Python environment.
How to Install adal on Windows?
- Type
"cmd"in the search bar and hit
Enterto open the command line.
- Type “
pip install adal” (without quotes) in the command line and hit
Enteragain. This installs adal for your default Python installation.
- The previous command may not work if you have both Python versions 2 and 3 on your computer. In this case, try
"pip3 install adal"or “
python -m pip install adal“.
- Wait for the installation to terminate successfully. It is now installed on your Windows machine.
Here’s how to open the command line on a (German) Windows machine:
First, try the following command to install adal on your system:
pip install adal
Second, if this leads to an error message, try this command to install adal on your system:
pip3 install adal
Third, if both do not work, use the following long-form command:
python -m pip install ad adal on Linux?
You can install adal on Linux in four steps:
- Open your Linux terminal or shell
- Type “
pip install adal” (without quotes), hit Enter.
- If it doesn’t work, try
"pip3 install adal"or “
python -m pip install adal“.
- Wait for the installation to terminate successfully.
The package is now installed on your Linux operating system.
How to Install adal on macOS?
Similarly, you can install adal on macOS in four steps:
- Open your macOS terminal.
- Type “
pip install adal” without quotes and hit
Enter.
- If it doesn’t work, try
"pip3 install adal"or “
python -m pip install adal“.
- Wait for the installation to terminate successfully.
The package is now installed on your macOS.
How to Install adal in PyCharm?
Given a PyCharm project. How to install the ad
"adal"without quotes, and click
Install Package.
- Wait for the installation to terminate and close all pop-ups.
Here’s the general package installation process as a short animated video—it works analogously for adal if you type in “adal” in the search field instead:
Make sure to select only “adal” because there may be other packages that are not required but also contain the same term (false positives):
How to Install adal in a Jupyter Notebook?
To install any package in a Jupyter notebook, you can prefix the
!pip install my_package statement with the exclamation mark
"!". This works for the adal library too:
!pip install my_package
This automatically installs the adal library when the cell is first executed.
How to Resolve ModuleNotFoundError: No module named ‘adal’?
Say you try to import the adal package into your Python script without installing it first:
import adal # ... ModuleNotFoundError: No module named 'adal'
Because you haven’t installed the package, Python raises a
ModuleNotFoundError: No module named 'adal'.
To fix the error, install the adal library using “
pip install adal” or “
pip3 install adal” in your operating system’s shell or terminal first.
See above for the different ways to install ad. | https://blog.finxter.com/how-to-install-adal-in-python/ | CC-MAIN-2022-33 | refinedweb | 518 | 65.42 |
How to Complete Schedule M for Estate Form 706
Use Schedule M: Bequests, etc. to surviving spouse, when filing the federal estate tax return (Form 706), to report property passed to the decedent’s surviving spouse. Property passed to the spouse as a result of the decedent’s death qualifies for the unlimited marital deduction. This deduction may not apply if the surviving spouse is not a U.S. citizen, or if the spouse receives terminable interest property.
With the unlimited marital deduction, no tax is due on the death of the first spouse to die. When the second spouse dies, his or her estate pays any tax due on the remaining assets of both spouses.
What qualifies for the marital deduction?
Any assets held solely in the decedent’s name or jointly with the surviving spouse qualify for the marital deduction. The following items also qualify:
Trust qualifying for marital deduction: Property left in trust for a surviving spouse qualifies for the marital deduction if the surviving spouse is the sole beneficiary, is entitled to receive all the income for life, can withdraw any/all of the principal at any time, and has a general power of appointment.
Life insurance, endowments, and annuity contracts: Proceeds from these assets qualify, if they are payable to the spouse, and meet the conditions specified in the Form 706 instructions.
Qualified terminable interest property (QTIPs): If a QTIP trust exists, you can elect to claim a marital deduction for qualified terminable interest property by listing the property on Schedule M and deducting it. If you elect out of the QTIP, you forgo this marital deduction. In either case, list the property on Schedule M.
When choosing to elect out of the QTIP, always identify the trust as being excluded from the election. Remember that any property for which the election is made will be included in the decedent’s spouse’s estate. Consult your tax advisor to be sure you meet all the requirements for making a valid QTIP election.
Joint and survivor annuities: If your decedent has a joint and survivor annuity with his or her surviving spouse, that spouse’s right to receive payments during his or her lifetime after the decedent’s death constitutes a QTIP election; a formal election isn’t necessary. As executor, however, you can affirmatively opt out of the election on Form 706.
Charitable remainder trusts: Interest in a charitable reminder trust is deductable if the interest passes from your decedent to the surviving spouse and that spouse is sole beneficiary of the trust (other than charitable organizations).
Qualified domestic trusts (QDOTs): A surviving spouse who isn’t a U.S. citizen doesn’t automatically qualify for the unlimited marital deduction unless the property is put into a QDOT for the benefit of that spouse.
If the decedent left a marital trust that doesn’t meet QDOT requirements, ask the probate court to reform the trust so that it qualifies. If your decedent left non-trust assets to the surviving spouse, the spouse or executor may establish a QDOT trust. The surviving spouse can then transfer assets left outright to him or her into this trust.
The terms of a QDOT are quite specific. Consult a qualified tax advisor if you need to follow this route.
Terminable interest: When is it deductible?
Terminable interest is an interest that terminates after the passage of time or upon the (non)occurrence of some contingency. Terminable interest property received by a surviving spouse is normally nondeductible because the IRS can’t collect estate tax on property when the spouse dies if the interest terminates beforehand. There are some exceptions:
Six-month survival period: If your decedent left a bequest to the surviving spouse on the condition that the spouse survives for a period not exceeding six months, it’s not considered a terminable interest, and will qualify for the marital deduction.
Deductions against the marital deduction: If you claim a deduction on Schedules J through L against any property you take as a marital deduction, you must reduce the amount of the marital deduction by the other deduction amount. If the marital deduction property has a mortgage or other encumbrance, you may take only the net value of the property after you deduct that encumbrance. | http://www.dummies.com/how-to/content/how-to-complete-schedule-m-for-estate-form-706.html | crawl-003 | refinedweb | 716 | 50.06 |
Edit Article
How to Create an XML Schema
An XML Schema defines the structure of your XML document. As opposed to XML DTDs (document type definitions) XML Schemas are more powerful and support both data types and namespaces. Knowing how to create an XML Schema will ensure proper functioning of your XML document
Steps
- 1Purchase an XML editing software program that allows you to create XML schemas, if you do not already have such software.
- 2Install the software on your computer and restart, if necessary.
- 3Familiarize yourself with your XML editor's workspace, as well as with user resources that are available.
- 4Create elements for your XML Schema.
- Your schema must include the schema element as its root element. This element may also contain attributes.
- Elements must include a start and end tag and may include other elements, text, attributes or any combination of these.
- The names of your XML elements must not start with a number or special character and cannot start with "xml."
- Ensure all elements are properly nested.
- Use short, descriptive names for your elements.
- 5Define which XML Schema elements are child elements.
- 6Create your XML Schema attributes.
- Attributes provide additional information about the elements contained within your XML document.
- Attributes must appear within quotes.
- Attributes can contain only one value.
- Do not include tree structures in your attributes.
- 7Create your XML Schema types to define the content of your elements and attributes.
- 8Save your work.
- 9Check your XML Schema to be sure XML elements and XML attributes are properly named and that there are no other errors.
- 10Correct any errors you identify.
- 11Validate your XML Schema using your XML editor's validation tool.
- 12Correct any errors identified during validation.
- 13Save your work.
- 14Open the XML file or files for which you have created the XML Schema.
- 15Include a reference to your XML Schema within your XML file or files.
- 16Save your XML file.
Community Q&A
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Tips
-.
- Your XML Schema outlines elements and attributes that are allowable in your XML document. Your XML Schema also identifies child elements, as well as their number and order.
- The language used to create XML schemas is also called XML Schema Definition (XSD).
- By using an XML Schema instead of an XML DTD, it will be easier for you to describe what content is allowed, to work with data, define data facets and patterns, convert data and to validate your data.
Things You'll Need
- Basic understanding of HTML
- Basic understanding of XHTML
- Basic understanding of XML
- Basic understanding of XML namespaces
- Basic understanding of XML DTDs
- computer
- XML file or files
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Español: crear un esquema XML
Thanks to all authors for creating a page that has been read 23,102 times.
Did this article help you? | http://www.wikihow.com/Create-an-XML-Schema | CC-MAIN-2017-04 | refinedweb | 493 | 65.83 |
Prior to training a machine learning or deep learning model, it is important to cleanse, pre-process and analyse the dataset at hand. Processes like dealing with missing values, converting text data into numbers and so on are all part of the pre-processing phase. More often than not, these processes come across as being repetitive and monotonous. Although there are tools for automating this process, they behave like a black box and do not give intuition about how they changed the data. To overcome this problem, python introduced a library called dabl – Data Analysis Baseline library. Dabl can be used to automate many of the tasks that seem repetitive in the early stages of model development. This was developed quite recently and the latest version of Dabl was released earlier this year. The number of available features currently are less, but the development process is happening at a good pace at Dabl.
In this article, we will use this tool for data pre-processing, visualisation and analysis as well as model development. Let’s get started.
Data pre-processing
To use dabl to perform data analysis we need to first install the package. You can install this using the pip command as
pip install dabl
Once the installation is done, let us go ahead and pick a dataset. I will select a sample dataset from Kaggle. You can click this link to download the data. I have chosen the diabetes dataset. It is a small dataset which will make it easy to understand how dabl works.
After downloading the dataset, let us import the important libraries and look at our dataset.
import numpy as np import dabl import pandas as pd db_data=pd.read_csv('diabetes.csv') db_data.head()
Usually, after looking at the dataset you would get into the data cleaning process by trying to identify missing rows, identify the erroneous data and understand the datatypes of the columns. These processes are made easy using dabl by automating these.
db_clean = dabl.clean(db_data, verbose=1)
We have a list of detected feature types for the dataset given. These types indicate the following.
Continuous: This is the number of columns containing continuous values and columns with high cardinality.
Dirty_float: Float variables that sometimes take string values are called dirty_float.
Low_card_int: Columns that contain integers with low cardinality fall under this category.
Categorical: This is the number of columns containing pandas categorical values in a string, integer or floating-point formats.
Date: Columns with data in them. These are currently not handled by dabl.
free_string: string data types which contain multiple unique values are labelled as free_string.
Useless: Constant or integer values that do not match with any of the categories are given a name useless.
For more information about the feature types it has identified you can do the following step.
type_info = dabl.detect_types(db_clean)
type_info
Here, we can clearly see which column of the dataset is of which data type. We can also change the type to meet our needs and requirements. For example, the column named Pregnancies is labelled neither as continuous nor as categorical and since the values in the column are single integer values we can make them into categorical values.
db_clean = dabl.clean(db_data, type_hints={"Pregnancies": "categorical"})
We have successfully converted the column into a categorical one.
Data visualisation.
Using the plot() method you can plot all your features against the target. In our dataset, the column Outcome is the target.
dabl.plot(db_clean, 'Outcome')
Dabl first automatically identifies and drops any outliers present in the dataset. It then identifies what type of data is present in the target (whether is categorical or continuous) and then displays the appropriate graph. Since ours is a categorical target, the output is a bar graph containing the count of 0s and 1s. Dabl also calculates and displays Linear discriminant analysis scores for the training set.
The next graph is to identify the distribution of each feature against our target. As you can see below, each feature is plotted as a histogram against our target and the number of features that lead to 1 and 0 are shown in orange and blue respectively.
The next graph is the scatter plot of the different combinations of data that exists in the dataset. For example, the feature glucose will be plotted against all the other columns and the distribution is shown below.
In order to increase the efficiency and speed of training, dabl automatically performs PCA on the dataset and also shows the distribution to us. The next graph is the discriminant PCA graph for all the features in the dataset. It also displays the variance and cumulative variance for the dataset.
The final graph displayed here is the linear discriminant analysis which is done by combining the features against the target.
It is clear that in a single line of code we are able to analyse the data in different ways that would usually be done in multiple steps and with code redundancy. But dabl is not repetitive and is an automated way to make data visualisation easy and simple to use.
Model development
Dabl intends to speed up the process of model training and provides a low code environment to train models. It takes up very little time and memory to train models using dabl. But, as mentioned earlier, this is a recently developed library and provides basic methods for machine learning training. Here I will be using a simple classifier model to train the diabetes dataset.
classifier = dabl.SimpleClassifier(random_state=0) x = db_clean.drop('Outcome', axis=1) y = db_clean.Outcome classifier.fit(x, y)
The simple classifier method performs training on the most commonly used classification models and produces accuracy, precision, recall and roc_auc for the data.
Not only this, but it also identifies the best model giving the best results on your dataset and displays it.
Similar to classification, you can also use a simple regressor model for regression type of problem.
Conclusion
Dabl offers ways of automating processes that otherwise take a lot of time and effort. Faster processing of data leads to faster model development and prototyping. Using Dabl not only makes data wrangling easier but also makes it efficient by saving a lot of memory. The documentation of dabl indicated that there are some useful features still to come, including model explainers and tools for enhanced model building.. | https://analyticsindiamag.com/lets-learn-dabl-a-python-tool-for-data-analysis-and-ml-automation/ | CC-MAIN-2020-45 | refinedweb | 1,064 | 55.03 |
table of contents
- buster 4.16-2
- buster-backports 5.04-1~bpo10+1
- testing 5.10-1
- unstable 5.10-1
NAME¶move_pages - move individual pages of a process to another node
SYNOPSIS¶
#include <numaif.h>
long move_pages(int pid, unsigned long count, void **pages, const int *nodes, int *status, int flags);
Link with -lnuma.
DESCRIPTION¶move_pages() moves the specified pages of the process pid to the memory nodes specified by nodes. The result of the move is reflected in status. The flags indicate constraints on the pages to be moved.
pid is the ID of the process in which pages are to be moved. if move_pages() did not return an error. Preinitialization of the array to a value which cannot represent a real numa node or valid error of status array could help to identify pages that have been migrated.¶The following values can be returned in each element of the status array.
- 0..MAX_NUMNODES
- Identifies the node on which the page resides.
- -EACCES
- The page is mapped by multiple processes and can be moved only filesystem does not provide a migration function that would allow the move of dirty pages.
- -EINVAL
- A dirty page cannot be moved. The filesystem does not provide a migration function and has no ability to write back pages.
- -ENOENT
- The page is not present.
- -ENOMEM
- Unable to allocate memory on target node.
RETURN VALUE¶On success move_pages() returns zero. On error, it returns -1, and sets errno to indicate the error. If positive value is returned, it is the number of nonmigrated pages.
ERRORS¶
- Positive value
- The number of nonmigrated pages if they were the result of nonfatal reasons (since Linux 4.17). E2BIG Too many pages to move. Since Linux 2.6.29, the kernel no longer generates this error.
-¶move_pages() first appeared on Linux in version 2.6.18.
CONFORMING TO¶This system call is Linux-specific.
NOTES¶For. | https://manpages.debian.org/testing/manpages-dev/move_pages.2.en.html | CC-MAIN-2021-04 | refinedweb | 319 | 69.28 |
Project Description:
Enhance the Firefox add-on called Link Gopher.
Fix context menu background. It worked in FF 3-17, but in FF 18 the background became transparent.
Change the context menu (from the add-ons toolbar) to have these options: About Link Gopher, extract links for current page, extract links for all tabs, and extract links for current selection. (These options work as described.)
Add the same options to the tools menu. The main menu entry (under Tools) is Link Gopher, and the Link Gopher menu has these options: extract links for current page, extract links for all tabs, and extract links for current selection. (These work just like the context menu.)
Make the results page interactive.
* Add a checkbox "sort and de-duplicate." By default it is enabled. When it is enabled, the results are sorted and de-duplicated.
* Add a checkbox "image links." By default it is not enabled. When it is enabled, image links are included.
* Add a text box labeled "filter" to filter the results. The results filter in real time after each keystroke.
* For the filter add a dropdown which shows recent filters. A user can click an item to populate the "filter" text box.
* A filter is added to the history when the results page is closed.
* The history keeps the most recent 5-20 items (at your discretion).
* For the filter option, add a checkbox "regular expression." By default it is disabled. When enabled, the search is done by regex.
* After the results page or Firefox is closed, the results page remembers these options.
In the Add-ons Bar, replace the text "Links" with an icon to be provided.
The first time a user starts Firefox with a different (new) version of Link Gopher installed, open the URL
The extension must work on Firefox 18 on Windows and Linux.
The add-on must be acceptable to Mozilla's standards for addons.mozilla.org. In particular a namespace may need to be implemented as described here
You surrender copyright. The code must be your own; otherwise, it must be marked as such and license-able under the GNU General Public License v3+
Follow best coding practices to create maintainable, quality code such as appropriate naming of objects and code comments.
This project is not time sensitive. I am looking for someone with Firefox and JavaScript experience and who appreciates working for donations collected by Link Gopher.
For the milestones, I suggest 50% to be delivered when the extension is delivered and seems to work on my system, and the other 50% awarded when the extension is approved by Mozilla. | http://www.freelancer.com/projects/Javascript-HTML.1/enhance-existing-Firefox-extension.4203110.html | CC-MAIN-2014-10 | refinedweb | 436 | 66.94 |
advice on compiling a c++ project to a standalone console executable
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orbs, in C++ / C / Win32
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- By jamesbowers
Hi guys! I have a problem that i hope you give me an advice to solve it. I have writing this code and it doesn't run cuz its a problem.
C2562 'Draw':'void' function returning a vaue.....
I dont know what to correct.
- By Dragonfighter
Autoit version: 3.3.14.5
System: Windows 10 Home x64
C++ IDE: Code::Blocks 17.12
When I call the Dll that I wrote it give me how return value -1073741819 and exit value 3221225477, I tried changing variables type but it didn't work.
This is the Autoit code:
#Region ;**** Directives created by AutoIt3Wrapper_GUI **** #AutoIt3Wrapper_UseX64=n #EndRegion ;**** Directives created by AutoIt3Wrapper_GUI **** $dll = DllOpen(@ScriptDir & "\Test.dll") DllCall($dll, "NONE", "TestFunction", "STR", "1 string", "STR", "2 string", "STR", "3 string", "INT", 1) ;Here crash and doesn't show the MsgBox MsgBox(0, "", @error) DllClose($dll) This is the main.cpp code:
#include <iostream> #include <Windows.h> #include "main.h" using namespace std; extern "C" { DECLDIR void TestFunction(std::string string1, std::string string2, std::string string3, int number1) { std::cout << string1 << std::endl; std::cout << string2 << std::endl; std::cout << string3 << std::endl; std::cout << number1 << std::endl; } } And that is the main.h:
#ifndef _DLLTEST_H_ #define _DLLTEST_H_ #define DLL_EXPORT #if defined DLL_EXPORT #define DECLDIR __declspec(dllexport) #else #define DECLDIR __declspec(dllimport) #endif extern "C" { DECLDIR void TestFunction(std::string string1, std::string string2, std::string string3, int number1); } #endif
And the values of the variables that write to the SciTe console ae completely different.
Here I attach the console output of the SciTe editor:
>"C:\Program Files (x86)\AutoIt3\SciTE\..\AutoIt3.exe" "C:\Program Files (x86)\AutoIt3\SciTE\AutoIt3Wrapper\AutoIt3Wrapper.au3" /run /prod /ErrorStdOut /in "C:\Users\DragonFighter\Desktop\Dll test.au3" /UserParams +>10:30:08 Starting AutoIt3Wrapper v.17.224.935.0 SciTE v.3.7.3.0 Keyboard:00000410 OS:WIN_10/ CPU:X64 OS:X64 Environment(Language:0410) CodePage:0 utf8.auto.check:4 +> SciTEDir => C:\Program Files (x86)\AutoIt3\SciTE UserDir => C:\Users\DragonFighter\AppData\Local\AutoIt v3\SciTE\AutoIt3Wrapper SCITE_USERHOME => C:\Users\DragonFighter\AppData\Local\AutoIt v3\SciTE >Running AU3Check (3.3.14.5) from:C:\Program Files (x86)\AutoIt3 input:C:\Users\DragonFighter\Desktop\Dll test.au3 +>10:30:08 AU3Check ended.rc:0 >Running:(3.3.14.5):C:\Program Files (x86)\AutoIt3\autoit3.exe "C:\Users\DragonFighter\Desktop\Dll test.au3" --> Press Ctrl+Alt+Break to Restart or Ctrl+Break to Stop �Á+���Uø‰q�‰A�‹O`ÆEÿ�èèÖÿÿƒÄ €}ÿ!>10:30:10 AutoIt3.exe ended.rc:-1073741819 +>10:30:10 AutoIt3Wrapper Finished. >Exit code: 3221225477 Time: 3.414
Thanks in advance for every reply.
- Dragonfighter
#include <iostream> #include <fstream> #include <string> int main () { std::ifstream is ("image.png", std::ifstream::binary); unsigned char buffer_array[4][4]; if (is) { is.seekg (0, is.end); int length = is.tellg(); is.seekg (0, is.beg); char * buffer = new char [length]; is.read (buffer,length); //Here I get the error unsigned char * buffer_str=buffer; for (int count1=0; count1<4; count1=count1+1) { for (int count2=0; count2<4; count2=count2+1) { //Here I get the others two errors buffer_array[count1][count2]=buffer_str.substr(0, 2); buffer_str.erase(0, 2) }; }; return 0; }; }; My goal is to split the binary buffer of the image.png in an array, I tried using string modifiers but I get two errors: request for member 'erase' in 'buffer_str', which is of non-class type 'unsigned char*' thats what I get when build.
- | https://www.autoitscript.com/forum/topic/198158-advice-on-compiling-a-c-project-to-a-standalone-console-executable/ | CC-MAIN-2021-04 | refinedweb | 612 | 51.75 |
This is on WinXP, SP2, JDK 1.6.0_u11, Jython 2.5.0+ (the default).
I debugged a simple python script stepping over a few statements using F8 and then stopped the debug session.
This behaviour 100% reproducible.
Thread dumps are attached.
Georg
Created attachment 74664 [details]
zip file containing 4 thread dumps taken with jstack -l
in order to be able to reproduce , attach a sample + describe the scenario leading to the problem.
Thanks
Jean-Yves
The scenario is obviously already described in the bug report: single step through a python script and
then stop the debugging session - it is really that simple (what do you expect me to do? Firing up Camtasia to create a
movie to show you how I am debugging a simple 5 line python script?)
Like this:
def foo(bar):
for i in range(bar):
print i
foo(10)
After 5 times through the loop stop the debugging session. NB hangs.
The jstack output should tell you what is going on.
The problem I am having now: I tried to test with native Python 2.6 and now NB ends up in a tight endless loop while
indexing python 2.6 after startup. I need to find out first, how to get NB in workable state again, before I can
continue (ok, I removed python 2.6 to get off the hook).
Thanks for reporting the problem using the python script you provided or other python scripts.
I can't reproduce the hang at all on Windows using either the bundled Jython or Python 2.6. I tried on both Python EA
(both Jython and Python 2.6) and the latest development build 257 (only Jython since there's regression so no new pyhton
platform can be added). Which Python build are you using (EA or dev build)?
Now I tried the same on a different box, a Dell Studio 17 with Vista Home Premium, JDK1.6.0_11, NB 6.5, Python EA 0.100.
Other scripting language support is installed (PHP, JavaFX 1.0).
I used the same script and stepped through it using F8. After pressing F8 on the line that says "foo(1)" the number 1 to
10 are printed in the output window and now NB hangs.
I am attaching the usual thread dump (I thought thread dumps are usually sufficient to find the cause of a lock-up(?)).
Georg
Created attachment 74734 [details]
jstack -l output after NB locked up
FWIW: foo(1) should have read foo(10)...
Created attachment 74735 [details]
NB after final F8
Although my dvp box is linux , I tried your sample + scenario on dev #265 in both jython or python contexts withou being
able to reproduce it on a linux box either.
When you press the stop button the action behind is just sending a STOP command to the Python debugger backend script
over the debugging ip session on 127.0.0.1 ; since previous debugging stepping have been working I do not see any
reason of hanging there in the code.
So I changed the status to worksforme
verified in the python EA build on Windows Vista using jdk 1.6.0_11 or jdk 1.6.0_07 and I could reproduce the problem. I
have not been able to reproduce this before though until now. I could not reproduce it before because I did not have
JavaFX installed but I have the full 6.5 installed. I just installed JavaFX 1.0 yesterday to take a look at JavaFX.
While having JavaFX installed, I tried to verify this issue and I could reproduce it every time. Not even stepping into
the debugging session. Starting debugging already froze ide. After I uninstalled JavaFX, this problem is no longer
reproducible. So, it looks like there's some incompatibility with JavaFX. Not sure if it's only python that has this
problem or other modules also have this. I'll install JavaFX again and try debugging other modules like Java, Ruby, etc,
next week.
I'm reopening this issue for now as a reminder till next week.
Thanks for not being content with a WORKSFORME, but instead going the extra mile and continuing the investigation into
this! As a first result there is a work-around now, although a heavy-handed one (uninstalling JavaFX support).
Georg
I am able to reproduce the hang on Mac. My scenario was NB6.5 installed with Python EA and python project created.
Debugging and stopping after a few iterations of:
def foo(bar):
for i in range(bar):
print i
foo(10)
No problems. Then I installed JavaFX sdk for mac and JavaFX plugin repeated the debugging/stop debugger and NB hangs.
Thanks for Tony for confirming this on Mac. And thanks Georg for confirming again. Looks like it's really the JavaFX
that causes the hang. I'll see where this issue should be categorized.
The more general aspect here is one plugin breaking others, indicating that NB is susceptible to the plugin hell phenomenon.
Since it has been clearly identified that this problem occurs only with javafx, I switched this problem to WONTFIX on
my side for following reasons :
- javafx is neither part of 6.5 python trunk nor part of the 7.0 mercurial main trunk => I can't get the javafx plugin
sources which looks part of experimental stuff in nb cluster.properties.
- javafx is not officially available on linux / solaris => No way for me to get it working on my dvp platform.
- I would have been happy to start a netbeans debug session with javafx activated to reproduce the problem ... But i do
not have the necessary stuff to do it.
- More generally I think that this problem should be relative to javafx instabilities around GUI stuff and that the
python debugger is just a debug case of GUI freezing to be submitted to the javafx guys.
If they raise any problem in python code just reassign this ticket to me then.
Jean-Yves
Jean-Yves,
I strongly protest against closing this issue with WONTFIX before a corresponding bug report has been entered on the
JavaFX side! Please keep it open until then. Moreover you need to prove that this bug is not related to Python before
you can close it in this way and I don't think we have enough information yet.
If you do not have the means, you should talk to your supervisor to provide them (if Sun publishes stuff that runs only
on Windows and Mac, it has to give its engineers the means to investigate bugs on these platforms. Everything else would
be pointless). That you currently are limited to Linux or Solaris is in no way a justification to close a bug report.
(If you need a Windows installation, maybe you can deploy XP or Vista in a virtualized environment).
Sorry for taking so long on this issue. I agree with Georg to keep this open. I emailed to the person on the javafx side
but haven't heard anything. I'd just recategorize this issue to javafx. If they decide this is in python after
evaluation of the problem, they can change it back to python.
Peter ,
Keep it open is fine by me , And I am also more than happy to look at any python reason to break javafx ....( and that
was preciselly what I was going to do before switching to WONTFIX) ... assuming that I got informations about javafx
netbeans plugin source location which is not on the main 7.0 trunk right now which makes it impossible to me to start a
remote debug session on this case.
So to sumarize my WONTFIX was a WONTFIX because I do not have involved last javafx sources available somewhere on
mercurial + specific building rules if any to be able to debug the situation WITH JAVAFX PLUGIN SOURCES.
Jean-Yves,
I understand. In this case, let's let the javafx take the first evaluation then. Thanks.
In the stack trace I see a deadlock in org.netbeans.modules.python.debugger.actions.JpyDbgView:
- org.netbeans.modules.python.debugger.PythonDebugger locks org.netbeans.modules.python.debugger.actions.JpyDbgView
(probably wrong usage of synchronized method) and then terminates the debugger session with firing all the changes
through DebuggerManager, where one of the listeners invokes some code through SwingUtilities (requiring AWT thread to
perform).
- at the same time is org.netbeans.modules.python.debugger.actions.JpyDbgView called from AWT thread but locked
I think that JpyDbgView should solve internal synchronization more safely. It is dangerous to use critical sections when
called from AWT and when notifying listeners of DebuggerManager from the critical section at the same time.
We may also remove SwingUtilities request from our DebuggerManager listener
(org.netbeans.modules.debugger.javafx.projects.EditorContextImpl), but the deadlock may manifest on some other
DebuggerManager listener in the future.
Fixed in 7.0 trunk build #545 and above
(critical section improvement in python debugger stop action) | https://netbeans.org/bugzilla/show_bug.cgi?id=154875 | CC-MAIN-2017-17 | refinedweb | 1,493 | 65.12 |
I have this script that apparently isn't working. The goal of the script is to randomly select a target from an array of "allies" (or the player and player hirelings) in another script. What this script is supposed to do is go through each of the objects in the list of "allies", add the array location number to a local array (TargetsInLOS). This should result in a bunch of array location numbers in the TargetsInLOS, in which a random number from here is called and finally a return the number. The returned number should be the array location from the "Allies" list that is in the line of sight of the enemy.
Hopefully I commented enough to show my thinking / reasoning
int GetTargetSelection() {
int[] TargetsInLOS = new int[0]; // List of the target selections that will be filled with selection variables in line of sights
int selection2 = 0; // Selection for each of the gameobjects for the "ForEach" part
foreach (GameObject item in EntitiesDataBase.Allies) {
// The script below works, all it does is set LOS to true if there is a line of sight between the two vector3 positions
CalculateLineOfSight(transform.position, item.transform.position);
if (LOS == true) {
// This works on another script, so hopefully this isn't the problem, but just incase...
// Stores the current variables of TargetInLOS into a storage array
int[] Storage = TargetsInLOS;
// Sets the TargetInLOS to a new array with a length of it's original length + 1
int var1 = TargetsInLOS.Length + 1;
TargetsInLOS = new int[var1];
//Replacing back the variables from storage into TargetInLOS
int selection = 0;
foreach (int item1 in Storage) {
TargetsInLOS.SetValue(item, selection);
selection += 1; // Setting it so the next item will go into the next array insert
}
TargetsInLOS.SetValue(selection2, TargetsInLOS.Length - 1); // Setting the final value to the selection of the original item that has a line of sight
}
selection2 += 1; // Setting is so the next item will go into the next array insert
}
int selection1 = Random.Range(0, TargetsInLOS.Length); //Picks a random number from the selection provided
return (TargetsInLOS[selection1]); // Returns the selection of a random target that is "seen" by the enemy, which is used for aquiring the gameobject
}
I don't really know anything Too Too advanced, and I don't really feel like changing the allies array to a list, as I already have it "infused" with all my other scripts
this script may actually be in working order, I found later that it was the Line of Sight calculator that was only working for just the player and not any other entitiy, so that was changed...
So does it work now?
So far it seems to work... the fine tuning now just needs to be done to the line of sight.
Distribute terrain in zones
3
Answers
Multiple Cars not working
1
Answer
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1
Answer
new Mesh() works outside of array, but not in array. Huh?
3
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Answers | https://answers.unity.com/questions/1282159/auto-targetting-script-not-working.html | CC-MAIN-2020-50 | refinedweb | 495 | 53.24 |
#include <wx/event.h>
This class is used for drop files events, that is, when files have been dropped onto the window.
This functionality is currently only available under Windows.
The window must have previously been enabled for dropping by calling wxWindow::DragAcceptFiles().
Important note: this is a separate implementation to the more general drag and drop implementation documented in the Drag and Drop Overview. It uses the older, Windows message-based approach of dropping files.
The following event handler macros redirect the events to member function handlers 'func' with prototypes like:
Event macros:
wxEVT_DROP_FILESevent.
Constructor.
Returns an array of filenames.
Returns the number of files dropped.
Returns the position at which the files were dropped.
Returns an array of filenames. | https://docs.wxwidgets.org/3.0/classwx_drop_files_event.html | CC-MAIN-2019-09 | refinedweb | 121 | 51.14 |
Using Styles, Themes, and Painters with LWUIT
- Contents
The Lightweight User Interface
Toolkit (LWUIT) introduces a number of impressive
functionalities to the "">Java ME UI developer.
Styles, themes, and painters are three such functionalities that
facilitate the development of highly attractive and device-independent visual elements. In this article, we see how to use them
and explore some of the subtle issues.
The demo applications have been developed on the
"">
Sprint Wireless Toolkit 3.3.1. concept of style is the foundation on which
theming is built. The idea behind style is to centrally
define the visual attributes for each component. In addition to its
physical design, such as its shape, the appearance of a widget can
be defined in terms of a number of common features:
Background and foreground colors: Each component has
four color attributes: two each for background and foreground. A
component is considered selected when it is ready for activation.
When a button receives focus, for example, it is in the selected
state and can be activated by being clicked. A component can
have a background color for the selected state and another for the
unselected one. Similarly, the foreground color (usually the color
used for the text on the component) can be individually defined for
the two states.
Text fonts: Text can be rendered using the standard
font styles as supported by the platform, as well as bitmap fonts.
The font for each component can be set through its style
object.
Background transparency: The transparency of a
component's background can be set to vary from fully opaque (the
default setting) to fully transparent. The integer value 0
corresponds to full transparency and 255 to complete opacity.
Background image: By default, the background of a
component does not have any image. However, this setting can be
used to specify an image to be used as the background.
Margin and padding: The visual layout of a component
(derived from the "">CSS Box Model) defines
margin and padding. Figure 1 shows the meaning of the terms
margin and padding in the context of LWUIT. Note that
the content area is used for displaying the basic content
such as text or image.
Styleallows margin and
padding for each of the four directions (top, bottom, left,
and right) to be individually set.
Figure 1. Component layout
Background painters:
Special-purpose painter objects can be used to customize the
background of one or a group of components.
The
Style class represents the collection of all
these attributes for each component that is used in an application
and has appropriate accessor methods. In addition, this class also
has the ability to inform a registered listener when the style
object associated with a given component is altered.
When a component is created, a default
Style object
gets associated with it. For any non-trivial application, the
visual attributes will need to be modified. One way of doing this
is to use the individual setter methods. "setter">If, for instance, the foreground color of a component
(
thiscomponent) has to be changed to red, the following code
can be used:
[/prettify][/prettify]
[prettify] thiscomponent.getStyle().setFgColor(0xff0000);
The second way to modify the settings of the default style is to
create a new style and hook it up to the relevant component. The
Style class has constructors that allow most of the
attributes to be specified. The following code snippet sets a new
style for a component:
[/prettify][/prettify]
[prettify] Font font = Font.createSystemFont (Font.FACE_SYSTEM,Font.STYLE_BOLD,Font.SIZE_LARGE); byte tr = (byte)255; Style newstyle = new Style (0x00ff00, 0x000000, 0xff0000, 0x4b338c, font, tr); thiscomponent.setStyle(newstyle);
This code sets new foreground and background colors, font for
text, and background transparency. The constructor used here has
the form:
[/prettify][/prettify]
[prettify] Style(int fgColor, int bgColor, int fgSelectionColor, int bgSelectionColor, Font f, byte transparency)
There is another form of this constructor that allows the image
to be set, in addition to the above attributes. The attributes not
supported by the constructor will, however, need to be set through
the respective setter methods.
Finally, visual attributes can also be set for an entire class
of components (say, for all labels in an application) by using a
theme, as we shall see a little later.
Using
Style
We shall now build a simple display and see how style can be
used to specify the appearance of a component. Our application will
have a single form with a combo box and will look like the Figure
2:
Figure 2. A simple combo box
All the attributes of the combo box shown here have default
values. The only exception is the foreground selection color, which
had to be changed to improve the visibility of the selected item.
Similarly, the form containing the combo box has just one modified
attribute -- its background color. The following code shows how
the form is created:
[/prettify][/prettify]
[prettify] . . . //create a form and set its title Form f = new Form("Simple ComboBox"); //set layout manager for the form //f.setLayout(new FlowLayout()); //set form background colour f.getStyle().setBgColor(0xd5fff9); . . .
The first two lines of code are quite self-explanatory and
should be familiar to AWT/Swing developers. The third line sets the
background color attribute for the form.
The combo box is also instantiated in a similar manner:
[/prettify][/prettify]
[prettify] // Create a set of items String[] items = { "Red", "Blue", "Green", "Yellow" }; //create a combobox with String[] items ComboBox combobox = new ComboBox(items);
ComboBoxis a subclass of
Listand
needs a supporting data structure. Here we use a string array to
represent this data structure.
Once we have our combo box ready, we would like to change its
foreground selection color to improve readability. So we write a
line of code just as we had done for the form:
[/prettify][/prettify]
[prettify] combobox.getStyle().setFgSelectionColor(0x0000ff);
However, when we compile the code and run it, the result turns
out to be rather surprising -- the foreground color remains
unchanged! It works for the form, so why doesn't it work for a combo
box? To answer that question we need to keep in mind the basic
architecture of LWUIT. Like "">Swing,
LWUIT is designed around the MVC concept. So the entity that
renders a component is logically separate from the component
itself. Also, the rendering object for a combo box (among others)
needs to be a subclass of
Component, which means it
will have its own
Style. Every combo box is created
with its default renderer, which is an instance of
DefaultListCellRenderer. When a combo box is drawn,
the style used is that belonging to the renderer and that is why
setting the foreground selection color in the
Style
object for the combo box does not work. To make the setting
effective we have to modify the
Style object for the
renderer:
[/prettify][/prettify]
[prettify] //set foreground selection colour for //the default combobox renderer //this will work DefaultListCellRenderer dlcr = (DefaultListCellRenderer)combobox.getRenderer(); dlcr.getStyle().setFgSelectionColor(0x0000ff);
This time, when the code is compiled, it works.
Theme
In the preceding section, we saw how to set individual visual
attributes for a component. In an application with a large number
of UI components, setting attributes for each component can be a
tedious task and can also lead to errors. A
Theme
allows us to set, in a single place, the attributes for an entire
class of components..
A
Theme is a list of key-value pairs with an
attribute being a key and its value being the corresponding value.
An entry in the list might look like this:
[/prettify][/prettify]
[prettify] Form.bgColor= 555555
This entry specifies that the background color of all forms in
the application will be (hex) 555555 in the RGB format. A theme is
packaged into a resource file that can also hold other items
like images and bitmaps for fonts. The LWUIT download bundle
includes a resource editor that offers a simple way to
create a theme and package it into a resource file. The editor is
available in the util directory of the bundle.
Launch it by double-clicking on
the icon, and the editor will open as shown below. The Resource
Editor is also integrated into the Sprint WTK 3.3.1 and can be
accessed by selecting File -> Utilities -> LWUIT Resource Editor,
as seen in Figure 3.
Figure 3. The Resource Editor
To create a new theme, click the
+ button on
the left pane and a dialog for entering the name of the theme will
open. This is shown in Figure 4.
Figure 4. Creating a new theme
When you click OK, the name of the new theme
appears on the left pane. Click this theme label to get a blank
theme on the right pane, as seen in Figure 5.
Figure 5. The blank theme
To populate the blank theme, click the Add
button and the Add dialog will open. You can select a
component and an attribute from the top combo boxes on this dialog.
In Figure 6, the component selected is a form and the attribute
selected is background color. The RGB value of the color can
entered as a hex string in the space provided. You can also click
on the colored box next to the space to entering the color value.
This will open a color chooser, from which the value of the
selected color will be directly entered into the dialog.
"Adding an entry to the theme" />
Figure 6. Adding an entry to the theme
Click the OK button and the entry will appear
on the right panel of the main editor window. Note that entries can
be edited or removed by using the appropriate button. Once all
entries have been made, you can save it by selecting File -> Save
As. If you are using the Sprint WTK, then the resource file for an
application has to be in its res folder.
Now that we have seen how to create a theme, let us look at a
demo that illustrates its use. Our demo for this section also will
have combo boxes but will look a little more polished than the one
we have already seen. Figure 7 shows this demo screen. Note that
now the form has a background image and the combo boxes are built
around check boxes. Also, the title bar (at the top of the form) and
the menu bar (at the bottom) have background colors different from
the default (white).
"Demo screen with two combo boxes" />
Figure 7. Demo screen with two
combo boxes
Before looking at the theme that is responsible for this
difference in appearance, let us quickly check out the code used to
make the screen.
[/prettify][/prettify]
[prettify] //initialise the LWUIT Display //and register this MIDlet Display.init(this); try { //open the resource file //get and set the theme Resources r = Resources.open("/SDTheme1.res"); UIManager.getInstance(). setThemeProps(r.getTheme("SDTheme1")); } catch (java.io.IOException e) { //if there is a problem print a message on console //in this case default settings will be used System.out.println ("Unable to get Theme " + e.getMessage()); } //create a form and set its title Form f = new Form("ComboBox Example"); //set layout manager for the form f.setLayout(new FlowLayout()); //create two sets of items String[] items = { "Red", "Blue", "Green", "Yellow" }; String[] items2 = {"Sky", "Field", "Ocean", "Hill", "Meadow"}; //create two comboboxes with these items ComboBox comboBox = new ComboBox(items); ComboBox comboBox2 = new ComboBox(items2); //create new instances of CbPainter //and set them to combo boxes //so that a checkbox will be //the basic building block CbPainter cbp = new CbPainter(); comboBox.setListCellRenderer(cbp); CbPainter cbp2 = new CbPainter(); comboBox2.setListCellRenderer(cbp2); //add the two combo boxes to the form f.addComponent(comboBox); f.addComponent(comboBox2); //create an "Exit" command and add it to the form f.addCommand(new Command("Exit")); //set this form as the listener for the command f.setCommandListener(this); //show this form f.show();
then who calls it? does UIManager.setThemeProps() call it
on all existing components, or do I have to keep references
to all my components and call refreshTheme() on each one
or what? ca -->
Right at the beginning we see how to extract the theme from a
resource file. The theme is then set for the
UIManager
instance. Here we have installed the theme at the start. But when a
theme is set on the fly, some of the components of the form on
screen may not be visible and the effect of setting a theme on
these components is not predictable. To make sure that even the
components that are not visible have their styles properly updated,
you should call the
refreshTheme method:
[/prettify][/prettify]
[prettify] Display.getInstance().getCurrent().refreshTheme();
The form and the combo boxes are created just as in our example
in the preceding section. There is no
code that adds visual gloss to this demo, as all attributes are
specified in a
Theme. What is different here is that
instead of letting the combo boxes be drawn by the default
renderer, we have set our own renderers. This is shown by the
highlighted part of the code. These custom renderers make the combo
boxes look different.
The renderer itself is very simple. All it has to do is
implement the methods specified in the interface
ListCellRenderer. As we want our combo box to encapsulate a
checkbox, the renderer extends
CheckBox. The
drawComboBox method of the
DefaultLookAndFeel
class uses this renderer to get the component to be used for
drawing the combo box. In this case the component so obtained is a
checkbox, as we see from the code below.
[/prettify][/prettify]
[prettify] //objects of this class will be used to paint the combo boxes class CbPainter extends CheckBox implements ListCellRenderer { public CbPainter() { super(""); } //returns a properly initialised component //that is ready to draw the checkbox public Component getListCellRendererComponent (List list,Object value,int index,boolean isSelected) { setText("" + value); if (isSelected) { setFocus(true); setSelected(true); } else { setFocus(false); setSelected(false); } return this; } //returns the component required for drawing //the focussed item public Component getListFocusComponent(List list) { setText(""); setFocus(true); setSelected(true); return this; } }
It is not necessary that a combo box should look only like a
plain list or a checkbox. It can be built around some other
standard component or even around a totally new component with its
own unique look. Figure 8 shows a combo box that has a radio button
as its renderer.
"ComboBox with a radio button renderer" />
Figure 8. ComboBox with a radio button renderer
To see the theme that defines the look of our demo, you
will need the Resource Editor on your computer. "#launch">Launch either the Resource Editor that comes with the
LWUIT download or the one integrated into the Sprint Toolkit. Once
the Resource Editor opens, select File -> Open to
locate and open the resource file. The Resource Editor will show
SDTheme1 on the left panel under Themes.
Clicking SDTheme1 will display the details of the theme
on the right panel as shown in Figure 9.
Figure 9. The theme for the demo
The first point to note is that there is one entry at the bottom
that appears in bold letters. All such entries are the defaults.
In our example, the only component-specific font setting is for the
soft button -- the Exit button at left bottom corner.
The fonts for the form title and the combo box
string are not defined. These fonts will be rendered as per the
default setting.
In our earlier example, we saw that the selection color for the
text had to be set in the renderer. In the present example, we know
the rendering is actually being done by a checkbox renderer. So the
background and foreground colors have been defined for checkboxes
and, indeed, the colors for rendering the text and the text
background (both for the focussed and non-focussed states) are as
per these definitions. This can be seen in Figure 10.
"Foreground and background colours" />
Figure 10. Foreground and background colors
In the figure above we can also see the effect of checkbox
transparency value of 127 (semi-transparent). The three unselected
entries in the drop-down list have a dark tint because of this
transparency setting. You can experiment with this value to see how
these backgrounds change. Incidentally, when you make a change in
the theme, it is not necessary to rebuild the application. Just
save the resource file and click Run.
When a new theme is installed, all applicable styles are updated
except those attributes that have been manually altered by using
one of the accessor methods of the
Style class
discussed earlier. However, if you want the
new theme to be effective even for the attributes that have been
manually changed, then use one of the setters in
Style
that take two arguments, the second one being a Boolean variable.
For example:
[/prettify][/prettify]
[prettify] setFgColor(int fgColor, boolean override);
If the Boolean argument is set to
true when an attribute
is manually changed, then the values specified in the new theme will
override the manually set value too. The code will look like
this:
[/prettify][/prettify]
[prettify] thiscomponent.getStyle().setFgColor(0xff0000, true);
Painter
The
Painter interface allows the background of a
component to look the way you want. Recall our discussion on
style where we had seen that one of the attributes was "#bgp">background painter. In this section we shall see how a
simple background painter can be used.
Referring to our demo screenshot, the
color of the background on which the text has been drawn cannot be
changed through style or theme. The reason for this becomes clear
when we analyze the structure of a combo box, as shown in Figure 11,
and the sequence of rendering it.
"Structure of our combo box" />
Figure 11. Structure of our combo box
When a combo box needs to be redrawn (say, because it has just
received focus), the following sequence of events takes place.
- The obsolete combo box is deleted. This is done by drawing a
filled rectangle of the same size and with a transparency of 0
(fully transparent).
- Then the checkbox selection and the text are drawn.
- Next the combo button is drawn.
- And finally, the combo border is drawn.
We see now that the combo background is not redrawn after the
first step. So this part remains a fully transparent layer and it
is the form background that shows through. You can change the form
background color in the theme and you will see that this color
also becomes the combo background color.
If we now want to have a different color (or a pattern or an
image) on the combo background, we need to use a
Painter. We shall see what a simple painter looks like
and how to use it.
12345678901234567890123456789012345678901234567890123456789012345
-->
[/prettify][/prettify]
[prettify] public class ComboBgPainter implements Painter { private int bgcolor; public ComboBgPainter(int bgcolor) { this.bgcolor = bgcolor; } public void paint(Graphics g, Rectangle rect) { //probably redundant //but save the current colour anyway int color = g.getColor(); //set the given colour g.setColor(bgcolor); //get the position and dimension //of rectangle to be drawn int x = rect.getX(); int y = rect.getY(); int wd = rect.getSize().getWidth(); int ht = rect.getSize().getHeight(); //draw the filled rectangle g.fillRect(x, y, wd, ht); //restore colour setting g.setColor(color); } }
The code is simple enough -- all it does is draw a filled
rectangle using the color passed to the constructor. The rectangle
is drawn at the position and with the dimensions defined by
rect.
What we now have to do is hook up the painter to the combo box
that needs to have its background painted. We do it by adding the
highlighted line after the code instantiating the two combo boxes.
Note that only one combo box will have its background painted.
[/prettify][/prettify]
[prettify] //create two comboboxes with these items ComboBox combobox = new ComboBox(items); ComboBox combobox2 = new ComboBox(items2); //set the painter combobox.getStyle().setBgPainter (new ComboBgPainter(0x4b338c));
Figure 12 shows that the background of the combo box on the left
has been painted as expected. If we had wanted to paint the
background of the other combo box too, we would have used the same
painter. As a matter of fact, we could create an instance of the
painter and set the same instance on all combo boxes.
"Combo box with painted background" />
Figure 12. Combo box with painted background
Conclusion
We have seen how we can use
Style,
Theme, and
Painter to create a set of
visually attractive and uniform components with the LWUIT platform.
Recently LWUIT has been open sourced. A detailed study of the
source code is a very fascinating experience and will develop the
kind of insight required for proper utilization of this library and
also for interesting experimentation.
Resources
- src_codes.zip: Source code and
resource file for the demo applications.
- " "">
An Introduction to Lightweight User Interface Toolkit (LWUIT)": A bird's-eye view of LWUIT.
- Lightweight User
Interface Toolkit (LWUIT) project home: Has a link for source
code.
- ";jsessionid=4C6B6439C2D7FED7FC8067E0EB400D24?tab=1">
LWUIT download bundle
- Sprint Wireless Toolkit 3.3.1 can be downloaded from "">
here.
- Login or register to post comments
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- 20600 reads | https://today.java.net/pub/a/today/2008/09/23/using-styles-themes-painters-with-lwuit.html | CC-MAIN-2015-40 | refinedweb | 3,545 | 62.38 |
This is a continuation from the previous module... Program examples compiled using Visual C++ 6.0 (MFC 6.0) compiler on Windows XP Pro machine with Service Pack 2. Topics and sub topics for this Tutorial are listed below. You can compare the standard C file I/O, standard C++ file I/O and Win32 directory, file and access controls with the MFC serialization. So many things lor! Similar but not same. Those links also given at the end of this tutorial.
Figure 8: The file extension used is myext.
Figure 9: AppWizard step 6 of 6 for MYMFC17 project, using a CFormView class.
Figure 10: MYMFC17 project summary.
Figure 11: MYMFC17 dialog and its controls, similar to MYMFC16.
Figure 12: Message mapping for IDC_EDIT_CLEAR_ALL.
Figure 13: Message mapping for IDC_ CLEAR.
Figure 14: Adding member variables.
Figure 15: Adding and modifying Clear All menu properties.
Figure 16: Adding and modifying toolbar buttons properties.
Figure 17: Messages mapping for toolbar buttons.
Serialization has been added, together with an update command UI function for File Save. The header and implementation files for the view and document classes will be reused in example MYMFC18 in the next module. All the new code (code that is different from MYMFC16) is listed, with additions and changes to the AppWizard-generated code and the ClassWizard code in orange if any. A list of the files and classes in the MYMFC17 example is shown in the following table.
CStudent Class
The following steps show how to add the CStudent class (Student.h and Student.cpp).
Figure 19: Creating and adding new files for CStudent class to the project.
Figure 20: Creating and adding Student.cpp file to the project.
Listing 1: CStudent class.
The use of the MFC template collection classes requires the following statement in StdAfx.h:
#include <afxtempl.h>
The MYMFC17 Student.h file is almost the same as the file in the MYMFC17 project except the header contains the macro:
DECLARE_SERIAL(CStudent)
instead of:
DECLARE_DYNAMIC(CStudent)
Listing 2.
and the implementation file contains the macro:
IMPLEMENT_SERIAL(CStudent, CObject, 0)
instead of:
IMPLEMENT_DYNAMIC(CStudent, Cobject)
Listing 3.
The virtual Serialize() function has also been. | https://www.tenouk.com/visualcplusmfc/visualcplusmfc11sdia.html | CC-MAIN-2020-05 | refinedweb | 360 | 61.43 |
Hi,
I'm trying to compare two text files (outputs from a database and corresponding spatial table in a GIS) to check for errors. Basically, i'm assuming that the output from the database is correct and any missing/repeat numbers in the spatial table will be errors and should be reported. I've written the part of the program that searches for a specific number in the spatial output and returns the errors, but i can't work out how to change the number it's searching for.
Here's what i've done so far:
#include <string> #include <fstream> #include <iostream> #include <stdlib.h> using namespace std; fstream DBinput("DB.txt", ios::in); fstream SPinput("SP.txt", ios::in); fstream output("Errors.txt", ios::out); int i = 0; string correct; string word; void count(void); void SPcompare(void); void main(void) { while(DBinput >> correct) { //////// Presumably this is where the 'find number to search for' part should come in //////// SPcompare(); } } void SPcompare(void) { while(SPinput >> word) { count(); } if(i == 0) output << "Error - '" << word << "' has no matches in spatial database" << '\n'; else if(i > 1) output << "Error - '" << word << "' has " << i << " matches in spatial database" << '\n'; } void count(void) { if(word == "5") i++; }
As you can see, so far it only searches for how many times the specific number 5 appears in the SP.text file.
What i'd like it to do is read the DB.txt file, find the first number to search for, then find out how many times it appears in SP.txt, then move on to the next number in DB and repeat until the end, generating a txt file output of all the errors. The SP.txt file has every number containted within inverted commas, and the DB.txt file has each number at the beginning of a new line follow by a lot of " delineated text/
Any help would be greatly appreciated, as would any 'you're making this a lot more complicated that it needs to be, here's how you can solve your problem in fifteen seconds' :)
P.S apologies for length | https://www.daniweb.com/programming/software-development/threads/9434/help-with-error-checking-code | CC-MAIN-2017-43 | refinedweb | 350 | 65.66 |
Difference between revisions of "Creating Live Path Effects"
Latest revision as of 22:05, 28 February 2012
Instructions for making Live Path Effects.
Contents
How does LPE work?.
Groundwork
It is best to put your new effect in the /live_effects directory. Copy lpe-skeleton.cpp and lpe-skeleton.h to your files (say lpe-youreffect.cpp and lpe-youreffect.h), and rename everything from skeleton to your name.
In effect-enum.h: Add your effect to the enumeration: "enum EffectType". This way, Inkscape knows how to refer to your effect.
In effect.cpp:
-Add #include "live_effects/lpe-youreffect.h" (below //include effects )
-Add your effect to the "const Util::EnumData<EffectType> LPETypeData[INVALID_LPE]" array. This way, Inkscape knows how to tell the user what the name of the effect is and also how to write its name to SVG.
-Tell inkscape how to create it by inserting it in
... Effect* Effect::New(EffectType lpenr, LivePathEffectObject *lpeobj) ... case YOUREFFECT: neweffect = (Effect*) new LPEYourEffect(lpeobj); break; ... ...
.:
1) void doEffect (SPCurve * curve)
2) std::vector<Geom::Path> doEffect_path (std::vector<Geom::Path> & path_in)
3) Geom::Piecewise<Geom::D2<Geom::SBasis> > doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > & pwd2_in)
It is easy to replace the standard doEffect function with yours. Let's say you want to create your effect with the path types of the 3rd function. You have to declare that one for your effect in lpe-youreffect.h: they are already writting down in there, you just have to un-comment the one you want, and you can delete the other doEffect functions. You must do the same in lpe-youreffect.cpp.
The first 2 doEffect_xxxs receive the full <svg:path>, the 3rd (_pwd2) only continuous paths. What happens is that the default std::vector<Geom::Path> doEffect_path function splits the path into continuous parts (if there are more) and calls doEffect_pwd2 for each path part; then it combines the results again into its output std::vector<Geom::Path>. If you do not want this behavior but would like to use _pwd2, you must set the 'concatenate_before_pwd2' boolean to true in the constructor of your effect (see for example LPEBendPath).
A "copy" effect has already been put in the .cpp file, you have to spice that up to make it do what you want. It is best to have a look at the doEffect functions of other effects and lpe-skeleton.cpp to see what is possible and how to implement something!
Parameter types:
Your effect can have any number of parameters that you'd like. You have to define them in the .h file. "RealParam number" is already there in the skeleton file; you can delete this if you do not want that kind of parameter ofcourse. That is the location where you can put the parameters that you want.
You also have to initialise and register them, so Inkscape knows about them. This you should do in the .cpp file:
// initialise your parameters here: number(_("Float parameter"), _("just a real number like 1.4!"), "svgname", &wr, this, 1.2)
The arguments are respectively, the name of the parameter in the UI, the tooltip text, the name of the parameter in SVG, 2 parameters that you don't have to bother about (they are always the same), and finally the default value. You can also omit the default value.
And these lines register your parameter:
// register all your parameters here, so Inkscape knows which parameters this effect has: registerParameter( dynamic_cast<Parameter *>(&number) );
Available parameter types
Check the /live_effects/parameter dir for more up-to-date info; perhaps some parameter types were added! You have to include the .h file that belongs to the parameter type in your own .h file to be able to use that parameter type.
- ScalarParam: a number of type 'gdouble'.
include "live_effects/parameter/parameter.h"
(see lpe-slant.cpp to learn how to use this type)
- PathParam: a parameter that is a path. This is a single path! If the input for this parameter are multiple paths, it is converted to just one path.
include "live_effects/parameter/path.h"
(see lpe-skeletal.cpp to learn how to use this type)
- EnumParam: a parameter that lets the user choose between a number of options from a dropdown box.
include "live_effects/parameter/enum.h"
(see lpe-skeletal.cpp to learn how to use this type)
- BoolParam:
include "live_effects/parameter/bool.h"
- RandomParam:
include "live_effects/parameter/random.h"
This gives a random value between 0 and the value set by the user. See how to use it in lpe-curvestitch.cpp)
- PointParam: a parameter that describes a coordinate on the page.
include "live_effects/parameter/point.h"
The parameters will automatically appear in the Live Path Effects dialog!
LPE on group : get the entire bounding box
Some effects, such as Bend Path, need the information of the size of the entire Bounding Box of the item on which the effect is applied.
How to get the Bounding box of the item ?
in lpe-YourEffect.h :
#include "live_effects/lpegroupbbox.h"
Then inherit from GroupBBoxEffect :
class LPESkeleton : public Effect, GroupBBoxEffect {
Now we can use the original_bbox(SPLPEItem *) method. When it is called, it stores the bounding box dimensions in Geom::Interval boundingbox_X and Geom::Interval boundingbox_Y. So let's call it before the calculation of the effect :
- Overload the doBeforeEffect method
lpe-YourEffect.h :
virtual void doBeforeEffect (SPLPEItem *lpeitem);
lpe-YourEffect.cpp :
void LPEBendPath::doBeforeEffect (SPLPEItem *lpeitem) { original_bbox(lpeitem); }
And to set defaults values :
- the reset Defaults method lpe-YourEffect.h :
virtual void resetDefaults(SPItem * item);
lpe-YourEffect.cpp :
void LPEBendPath::resetDefaults(SPItem * item) { original_bbox(SP_LPE_ITEM(item)); } | https://wiki.inkscape.org/wiki/index.php?title=Creating_Live_Path_Effects&diff=cur&oldid=26704 | CC-MAIN-2021-25 | refinedweb | 936 | 50.12 |
a group. It allows them to offer their unique attributes too. This not only makes for a rich domain, but also one that can evolve with the business needs.
When a Java class extends another, we call it a subclass. The one extended from becomes a superclass. Now, the primary reason for this is so that the subclass can use the routines from the superclass. Yet, in other cases the subclass may want to add extra functionality to what the superclass already has.
With method overriding, inheriting classes may tweak how we expect a class type to behave. And as this article will show, that is the foundation for one of OOP's most powerful and important mechanisms. It is the basis for polymorphism.
What is Method Overriding?
Generally, when a subclass extends another class, it inherits the behavior of the superclass. The subclass also gets the chance to change the capabilities of the superclass as needed.
But to be precise, we call a method as overriding if it shares these features with one of its superclass' method:
- The same name
- The same number of parameters
- The same type of parameters
- The same or covariant return type
To better understand these conditions, take a class
Shape. This is a geometric figure, which has a calculable area:
abstract class Shape { abstract Number calculateArea(); }
Let's then extend this base class into a couple of concrete classes — a
Triangle and a
Square:
class Triangle extends Shape { private final double base; private final double height; Triangle(double base, double height) { this.base = base; this.height = height; } @Override Double calculateArea() { return (base / 2) * height; } @Override public String toString() { return String.format( "Triangle with a base of %s and height of %s", new Object[]{base, height}); } } class Square extends Shape { private final double side; Square(double side) { this.side = side; } @Override Double calculateArea() { return side * side; } @Override public String toString() { return String.format("Square with a side length of %s units", side); } }
Besides overriding the
calculateArea() method, the two classes override
Object's
toString() as well. Also note that the two annotate the overridden methods with
@Override.
Because
Shape is abstract, the
Triangle and the
Square classes must override
calculateArea(), as the abstract method offers no implementation.
Yet, we also added a
toString() override. The method is available to all objects. And since the two shapes are objects, they can override
toString(). Though it is not mandatory, it makes printing out a class' details human-friendly.
And this comes in handy when we want to log or print out a class' description when testing, for instance:
void printAreaDetails(Shape shape) { var description = shape.toString(); var area = shape.calculateArea(); // Print out the area details to console LOG.log(Level.INFO, "Area of {0} = {1}", new Object[]{description, area}); }
So, when you run a test such as:
void calculateAreaTest() { // Declare the side of a square var side = 5; // Declare a square shape Shape shape = new Square(side); // Print out the square's details printAreaDetails(shape); // Declare the base and height of a triangle var base = 10; var height = 6.5; // Reuse the shape variable // By assigning a triangle as the new shape shape = new Triangle(base, height); // Then print out the triangle's details printAreaDetails(shape); }
You will get this output:
INFO: Area of Square with a side length of 5.0 units = 25 INFO: Area of Triangle with a base of 10.0 and height of 6.5 = 32.5
As the code shows, it is advisable to include the
@Override notation when overriding. And as Oracle explains, this is important because it:
...instructs the compiler that you intend to override a method in the superclass. If, for some reason, the compiler detects that the method does not exist in one of the superclasses, then it will generate an error.
How and When to Override
In some cases, method overriding is mandatory - if you implement an interface, for example, you must override its methods. Yet, in others, it is usually up to the programmer to decide whether they will override some given methods or not.
Take a scenario where one extends a non-abstract class, for instance. The programmer is free (to some extent) to choose methods to override from the superclass.
Methods from Interfaces and Abstract Classes
Take an interface,
Identifiable, which defines an object's
id field:
public interface Identifiable<T extends Serializable> { T getId(); }
T represents the type of the class that will be used for the
id. So, if we use this interface in a database application,
T may have the type
Integer, for example. Another notable thing is that
T is
Serializable.
So, we could cache, persist, or make deep copies from it.
Then, say we create a class,
PrimaryKey, which implements
Identifiable:
class PrimaryKey implements Identifiable<Integer> { private final int value; PrimaryKey(int value) { this.value = value; } @Override public Integer getId() { return value; } }
PrimaryKey must override the method
getId() from
Identifiable. It means that
PrimaryKey has the features of
Identifiable. And this is important because
PrimaryKey could implement several interfaces.
In such a case, it would have all the capabilities of the interfaces it implements. That is why such a relationship is called a "has-a" relationship in class hierarchies.
Let us consider a different scenario. Maybe you have an API that provides an abstract class,
Person:
abstract class Person { abstract String getName(); abstract int getAge(); }
So, if you wish to take advantage of some routines that only work on
Person types, you'd have to extend the class. Take this
Customer class, for instance:
class Customer extends Person { private final String name; private final int age; Customer(String name, int age) { this.name = name; this.age = age; } @Override String getName() { return name; } @Override int getAge() { return age; } }
By extending
Person using
Customer, you are forced to apply overrides. Yet, it only means that you have introduced a class, which is of type
Person. You have thus introduced an "is-a" relationship. And the more you look at it, the more such declarations make sense.
Because, after all, a customer is a person.
Extending a Non-final Class
Sometimes, we find classes that contain capabilities we could make good use of. Let us say you are designing a program that models a cricket game, for instance.
You have assigned the coach the task of analyzing games. Then after doing that, you come across a library, which contains a
Coach class that motivates a team:
class Coach { void motivateTeam() { throw new UnsupportedOperationException(); } }
If
Coach is not declared final, you're in luck. You can simply extend it to create a
CricketCoach who can both
analyzeGame() and
motivateTeam():
class CricketCoach extends Coach { String analyzeGame() { throw new UnsupportedOperationException(); } @Override void motivateTeam() { throw new UnsupportedOperationException(); } }
Extending a final Class
Finally, what would happen if we were to extend a
final class?
final class CEO { void leadCompany() { throw new UnsupportedOperationException(); } }
And if we were to try and replicate a
CEOs functionality through another class, say,
SoftwareEngineer:
class SoftwareEngineer extends CEO {}
We'd be greeted with a nasty compilation error. This makes sense, as the
final keyword in Java is used to point out things that shouldn't change.
You can't extend a
finalclass.
Typically, if a class isn't meant to be extended, it's marked as
final, the same as variables. Though, there is a workaround if you must go against the original intention of the class and extend it - to a degree.
Creating a wrapper class that contains an instance of the
final class, which provides you with methods that can change the state of the object. Though, this works only if the class being wrapped implements an interface which means that we can supply the wrapper instead of the
final class instead.
Finally, you can use a Proxy during runtime, though it's a topic that warrants an article for itself.
A popular example of a
final class is the
String class. It is
final and therefore immutable. When you perform "changes" to a String with any of the built-in methods, a new
String is created and returned, giving the illusion of change:
public String concat(String str) { int otherLen = str.length(); if (otherLen == 0) { return this; } int len = value.length; char buf[] = Arrays.copyOf(value, len + otherLen); str.getChars(buf, len); return new String(buf, true); }
Method Overriding and Polymorphism
The Merriam-Webster dictionary defines polymorphism as:
The quality or state of existing in or assuming different forms
Method overriding enables us to create such a feature in Java. As the
Shape example showed, we can program it to calculate areas for varying shape types.
And more notably, we do not even care what the actual implementations of the shapes are. We simply call the
calculateArea() method on any shape. It is up to the concrete shape class to determine what area it will provide, depending on its unique formula.
Polymorphism solves the many pitfalls that come with inadequate OOP designs. For example, we can cure anti-patterns such as excessive conditionals, tagged classes, and utility classes. By creating polymorphic hierarchies, we can reduce the need for these anti-patterns.
Conditionals
It is bad practice to fill code with conditionals and
switch statements. The presence of these usually points to code smell. They show that the programmer is meddling with the control flow of a program.
Consider the two classes below, which describe the sounds that a
Dog and a
Cat make:
class Dog { String bark() { return "Bark!"; } @Override public String toString() { return "Dog"; } } class Cat { String meow() { return "Meow!"; } @Override public String toString() { return "Cat"; } }
We then create a method
makeSound() to make these animals produce sounds:
void makeSound(Object animal) { switch (animal.toString()) { case "Dog": LOG.log(Level.INFO, ((Dog) animal).bark()); break; case "Cat": LOG.log(Level.INFO, ((Cat) animal).meow()); break; default: throw new AssertionError(animal); } }
Now, a typical test for
makeSound() would be:
void makeSoundTest() { var dog = new Dog(); var cat = new Cat(); // Create a stream of the animals // Then call the method makeSound to extract // a sound out of each animal Stream.of(dog, cat).forEach(animal -> makeSound(animal)); }
Which then outputs:
INFO: Bark! INFO: Meow!
While the code above works as expected, it nonetheless displays poor OOP design. We should thus refactor it to introduce an abstract
Animal class. This will then assign the sound-making to its concrete classes:
abstract class Animal { // Assign the sound-making // to the concrete implementation // of the Animal class abstract void makeSound(); } class Dog extends Animal { @Override void makeSound() { LOG.log(Level.INFO, "Bark!"); } } class Cat extends Animal { @Override void makeSound() { LOG.log(Level.INFO, "Meow!"); } }
The test below then shows how simple it has become to use the class:
void makeSoundTest() { var dog = new Dog(); var cat = new Cat(); // Create a stream of animals // Then call each animal's makeSound method // to produce each animal's unique sound Stream.of(dog, cat).forEach(Animal::makeSound); }
We no longer have a separate
makeSound method as before to determine how to extract a sound from an animal. Instead, each concrete
Animal class has overridden
makeSound to introduce polymorphism. As a result, the code is readable and brief.
If you'd like to read more about Lambda Expressions and Method References shown in the code samples above, we've got you covered!
Utility Classes
Utility classes are common in Java projects. They usually look something like the java.lang.Math's
min() method:
public static int min(int a, int b) { return (a <= b) ? a : b; }
They provide a central location where the code can access often-used or needed values. The problem with these utilities is that they do not have the recommended OOP qualities. Instead of acting like independent objects, they behave like procedures. Hence, they introduce procedural programming into an OOP ecosystem.
Like in the conditionals scenario, we should refactor utility classes to introduce polymorphism. And an excellent starting point would be to find common behavior in the utility methods.
Take the
min() method in the
Math utility class, for instance. This routine seeks to return an
int value. It also accepts two
int values as input. It then compares the two to find the smaller one.
So, in essence,
min() shows us that we need to create a class of type
Number - for convenience, named
Minimum.
In Java, the
Number class is abstract. And that is a good thing. Because it will allow us to override the methods that are relevant to our case alone.
It will, for instance, give us the chance to present the minimum number in various formats. In addition to
int, we could also offer the minimum as
long,
float, or a
double. As a result, the
Minimum class could look like this:
public class Minimum extends Number { private final int first; private final int second; public Minimum(int first, int second) { super(); this.first = first; this.second = second; } @Override public int intValue() { return (first <= second) ? first : second; } @Override public long longValue() { return Long.valueOf(intValue()); } @Override public float floatValue() { return (float) intValue(); } @Override public double doubleValue() { return (double) intValue(); } }
In actual usage, the syntax difference between
Math's
min and
Minimum is considerable:
// Find the smallest number using // Java's Math utility class int min = Math.min(5, 40); // Find the smallest number using // our custom Number implementation int minimumInt = new Minimum(5, 40).intValue();
Yet an argument that one may present against the approach above is that it is more verbose. True, we may have expanded the utility method
min() to a great extent. We have turned it into a fully-fledged class, in fact!
Some will find this more readable, while some will find the previous approach more readable.
Overriding vs Overloading
In a previous article, we explored what method overloading is, and how it works. Overloading (like overriding) is a technique for perpetuating polymorphism.
Only that in its case, we do not involve any inheritance. See, you will always find overloaded methods with similar names in one class. In contrast, when you override, you deal with methods found across a class type's hierarchy.
Another distinguishing difference between the two is how compilers treat them. Compilers choose between overloaded methods when compiling and resolve overridden methods at runtime. That is why overloading is also known as compile-time polymorphism. And we may also refer to overriding as runtime polymorphism.
Still, overriding is a better than overloading when it comes to realizing polymorphism. With overloading, you risk creating hard-to-read APIs. In contrast, overriding forces one to adopt class hierarchies. These are especially useful because they force programmers to design for OOP.
In summary, overloading and overriding differ in these ways:
Conclusion
Method overriding is integral to the presentation of Java's OOP muscle. It cements class hierarchies by allowing subclasses to possess and even extend the capabilities of their superclasses.
Still, most programmers encounter the feature only when implementing interfaces or extending abstract classes. Non-mandatory overriding can improve a class' readability and consequent usability.
For instance, you are encouraged to override the
toString() method from the class
Object. And this article displayed such practice when it overrode
toString() for the
Shape types -
Triangle and
Square.
Finally, because method overriding combines inheritance and polymorphism, it makes an excellent tool for removing common code smells. Issues, such as, excessive conditionals and utility classes could become less prevalent through wise use of overriding.
As always, you can find the entire code on GitHub. | https://stackabuse.com/method-overriding-in-java/ | CC-MAIN-2021-21 | refinedweb | 2,576 | 55.64 |
On 19.Jul.2001 -- 07:33 PM, Torsten Curdt wrote:
>
> What do you mean by "get back"? What I was thinking of was:
I was refering to the form in which the posted form parameters are
represented for further processing. Currently, every form element
corresponds to a request parameter. XForms require each entire form to
correspond to one request parameter. If the suggested names for
elements are used, they're like
"formName/elementName/subElementName". From this one DOM object can be
constructed to hold all parameters of a form, just like XForms
expects. That would enable to delegate validation to xerces but is a
bit more costly.
> > > When a subpage is chosen to be viewed an intance of
> > > an DOMObject referring to the xform id needs to be
> > > looked up. If there is none, one needs to be created
> > > and registered. (Just like the Components in the ComponentManager)
> > > Creation means also passing the SAX events from the
> > > xform:instance data to the DOMObject. Now the DOMObject
> > > holds the expected XForm structure.
> >
> > I don't quite get what you're at. If this object contains the instance
> > data -- which is likely to be different for every invocation as partly
> > filled in forms return -- why should an instance get looked up?
>
> I want to save the DOMObject instances inside the session.
> Simplified:
>
> xform = (DOMObject)session.get("formid");
> if(xform == null){
> xform = new DOMObject();
> xform.setLexicalHandler(lexicalhandler);
> xform.setContentHandler(contenthandler);
> }
OK.
> Some kind of manager would be probably better?!
No idea.
> > If that's the caching concern again, I strongly believe that that is a
> > different concern and should be handled otherwise. E.g. if it's a XSP
> > that generates the form, it's up to cocoon to cache this request and
> > deliver a cached copy.
>
> Now I'm wondering where you are up to... ;)
Caching should be done locally only if we know a lot better how to do
it than cocoon. Otherwise we should rely on cocoon to do the caching.
> > > * Selection of the subpage based on the validation results
> >
> > See other reply.
>
> Could you please outline how you would want to do this?
> I don't really see the problem about this one.
I think we agree that this is independant of forms. I would suggest an
action that knows how many subpages exists (through a session
attribute or a parameter?). So the sitemap would read like
if validation == OK
if 0 < requestedPage < lastPage
showPage ( requestedPage )
else
showPage ( currentPage )
fi
else
showPage(currentPage)
fi
Where showPage(subpage) is a call to generate.
BTW something similar could be achieved with the
FilterTransformer. Output all subpages and the FilterTransformer
filters all but the current one from the output.
> > > Then I would propose a XFormTransformer that will
> > > extract the selected subpage fragment and add the
> > > value to the xform elements. Here is an example of
> > > what should come out of the transformer:
> >
> > What would that be exactly? Fill in the blanks in a form with values
> > from the instance data, like the SQLTransformer?
>
> yes
I hope a stylesheet would do, but I don't know for sure. Of course if
you intent to do calculations and look up you'd need your own
transformer. But that I fear would be quite application specific. Or
at least I wouldn't see it at the core of a forms package.
Your concern here is how to integrate with forms. Well, you could do
<form>
<instance>
<name><replace-me</name>
</instance>
</form>
And replace with a transformer.
> > With XSP as well.
> > > * taglib would mean to but multiple (sub)pages into
> > > one XSP page - I'm always afraid of the 64k limitation
> > > of XSP pages
> >
> > AFAIK this limitation is a per method limit. So putting each sub page
> > in a different method would circumvent it.
>
> Hm.. got me. I must admit I feel just more flexible and
> safer not to run into compile time / run time problems.
> Why would you want to go for a logicsheet?
I think it's the most flexible way to do. But I'm not religious on
that.
> > Again this is not compliant. But it is a problem to conform to it
> > here. What about different error conditions? Currently
> > FormValidatorAction offers a number of constraints that each may be
> > invalid. XForms specs only one arbitrary complex constraint returning
> > a boolean.
>
> What's the compliant method? I must have missed it in the spec.
That's the problem, there isn't one. XForms does not talk about error
messages :-(
> > > * DBMS comboboxes
> > I still think it's not a form issue. If you're not happy with your
> > DBMS caching the data, well, create an alternative way to contact the
> > DBMS and do the caching in that component like the descriptor caching
> > is done. After all, this might come in handy with other issues as
> > well.
>
> But still there is the output problem then!
What output problem? Is this again, that I think XSP and you think
transformer? It would be no very nice to have to employ a dozen
specialized transformers... but then cocoon2 is all about putting
pieces together. That's what I like so much about it. Like shell
programming in UNIX ;-)
> > > * output definition
> > > I think what is not quite clear (at least for me)
> > > from the XForms spec is what "output" means
> > > on selections aka choices. Is it the value
> > > or the text? Both is needed! So how do you specify
> >
> > I think as with HTML it's the value. If you'd need the text, add that
> > to the value as well.
>
> Arrrgh... NO! This becoming a real ugly hack then!!
> (not talking about weak browser implementation that
> might be swamped with long i18n text as values - just
> a fear)
I see. Shoping cart &c. List of purchased items, not nice to look up
their description more than once. But there's not much we could do
about it. If the HTML reads
<option value="123456">Some really long description of item</option>
The browser will return "123456" only. What could a forms package do
to this?
> > > * subpage navigation
> > Name the submit button as you like.
>
> No. There is a difference! Submitting
> a subpage is different from submitting
> the xform!! Submitting the xform means
> "placing the order" while submitting
> a subpage is a navigation inside the
> xform.
Right. But if we think about this in terms of HTML it boils down to
name the submit button a long the lines of "continue..." or "subpage 2
caption". If the device were XForms compliant, we wouldn't have to
deal with sub pages at all. Ah, that's probably a plus for a
FilterTransformer based solution.
> What about putting the whole multipage
> navigation thing into it's own namespace?
> Like:
> So we would have both topics separated.
Agreed.
> But we need a way to report the result
> of the form submission (success/failed)
> to the sitemap. Also a failed submit
> need to show the last page again.
Sure. We'll see. | http://mail-archives.apache.org/mod_mbox/cocoon-dev/200107.mbox/%3C20010720154621.H27405@bremen.dvs1.informatik.tu-darmstadt.de%3E | CC-MAIN-2015-14 | refinedweb | 1,161 | 75.5 |
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Hello maintainers,
If noone objects I'll add the following MACROS to
config/cmake/config/vxl_utils.cmake and test apply changes to vul/vil
to use them. I have attached the vxl_utils.cmake and a generated
test_include.cxx for your quick inspection.
--- First Macro
Motivated by the recent problem in vul's test_url.cxx with APPLE, I
tested a MACRO (attached below) that I have for generating the TEST
code for CMake in vul and vil (not in the io,algo subdirs, yet). In
summary, you don't need the test_driver.cxx that is currently
generated, and it replaces the ADD_EXECUTABLE/ADD_TEST commands with
the single line:
GENERATE_TEST_DRIVER(vul vul_test_sources vul vpl testlib vcl)
In case you need arguments passed, I've used the following convention
that works in vil:
SET(test_file_format_read_args ${CMAKE_CURRENT_SOURCE_DIR}/file_read_data)
SET(test_stream_args ${CMAKE_CURRENT_SOURCE_DIR}/file_read_data)
SET(test_convert_args ${CMAKE_CURRENT_SOURCE_DIR}/file_read_data)
SET(test_blocked_image_resource_args ${CMAKE_CURRENT_SOURCE_DIR}/file_read_data)
GENERATE_TEST_DRIVER(vil vil_test_sources vil vpl vul testlib vcl)
That is create a variable named after the file containing the test +
"_args" to hold the arguments.
I also had to manually change all tests to have a function with the
signature as in the following code, but in most cases this could be
done by redefining TESTMAIN:
//TESTMAIN(test_math_value_range);
int test_math_value_range(int, char*[])
{
testlib_test_start("test_math_value_range");
test_math_value_range();
return testlib_test_summary();
}
--- Second Macro
I have also created a GENERATE_TEST_INCLUDE, which replaces the two
lines adding the test_include.cxx file in the CMakeLists.txt, but also
generates the actual test_include.cxx. The command looks like:
GENERATE_TEST_INCLUDE(vil vil_sources "vil/")
#ADD_EXECUTABLE( vil_test_include test_include.cxx )
#TARGET_LINK_LIBRARIES( vil_test_include vil )
The way I generate it is that I take the vil_sources variable (from
the upper dir) and scan it for *.h files, then include it twice in the
generated test_include.cxx with the prefix "vil/" appended. Sample
output is appended for vil.
My only reservation with this is that I don't know if people have
manually added things to test_include.cxx that would need special
treatment. Also, it will add everything with a *.h extension including
impl things like:
#include <vil/file_formats/vil_png.h>
in vil (which is not a bad thing for a test, I guess).
----
Please, let me know any concerns or suggestions you may have.
--Miguel
Yes, I had the same problem. From the sourceforge website:
( 2006-07-13 09:23:52 - Project CVS Service, Project Shell Service,
Project Subversion (SVN) Service, SourceForge.net Web Site ) A
recent kernel exploit was released that allowed a non admin user to
escalate privileges on the host pr-shell1. We urge all users who
frequent this host to change their password immediately and check
their project group space for any tampering. As a precaution, we have
blocked access to all project resources by password until the user
resets their password. After the password has been reset, project
resources should be accessible within 5 minutes.
I changed my password and I can access CVS again.
--Matt Leotta
On 7/14/06, Miguel A. Figueroa-Villanueva <miguelf@...> wrote:
> Hello maintainers,
>
> Is anyone else having problems with the cvs developer access to vxl?
> It's giving me a permission denied error...
>
> --Miguel
>
>
> -------------------------------------------------------------------------
> Using Tomcat but need to do more? Need to support web services, security?
> Get stuff done quickly with pre-integrated technology to make your job easier
> Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo
>
> _______________________________________________
> Vxl-maintainers mailing list
> Vxl-maintainers@...
>
>
Hello maintainers,
Is anyone else having problems with the cvs developer access to vxl?
It's giving me a permission denied error...
--Miguel | http://sourceforge.net/p/vxl/mailman/vxl-maintainers/?viewmonth=200607&viewday=14&style=flat | CC-MAIN-2014-52 | refinedweb | 598 | 57.67 |
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java netbeans i am making project in core java using Netbeans. Regarding my project i want to know that How to fetch the data from ms-access... using netbeans
Struts - Struts
used in a struts aplication.
these are the conditions
1. when u entered into this page the NEXT BUTTON must disabled
2. if u enter any text
Struts Validator Framework - lab oriented lesson
already been built using Struts, it may be that only a combination of Struts...,
right now.It may take some time before JSF completely replaces Struts.
Java... in our
modelapp.
Any typical struts-based application, will have
Struts Forward Action Example
about Struts
ForwardAction (org.apache.struts.actions.ForwardAction). The ForwardAction is one of the Built-in Actions
that is shipped with struts framework... Struts Forward Action Example
... with that project.i have an idea do create webpage using netbeans 6.8 version
Open Source Web Frameworks in Java
Open Source Web Frameworks in Java
Struts
Struts Frame work.... Struts is maintained as a part of Apache Jakarta
project and is open source. Struts Framework is suited for the application
of any size. Latest
Need Project
Need Project How to develop School management project by using Struts Framework? Please give me suggestion and sample examples for my project
Struts Hibernate Integration
and you can download and
start working on it for your project or to learn Struts...
In this section we will write Hibernate Struts Plugin Java code...
Struts Hibernate
Struts Validation - Struts
Struts Validation Hi friends.....will any one guide me to use the struts validator...
Hi Friend,
Please visit the following links:
http | http://roseindia.net/tutorialhelp/comment/80816 | CC-MAIN-2014-42 | refinedweb | 1,934 | 67.25 |
1.1 anton 1: \ create a documentation file 2: 1.6 ! anton 3: \ Copyright (C) 1995: 21: 22: \ the stack effect of loading this file is: ( addr u -- ) 23: \ it takes the name of the doc-file to be generated. 24: 25: \ the forth source must have the following format: 1.2 pazsan 26: \ .... name ( stack-effect ) \ [prefix-] wordset [pronounciation] 1.1 anton 27: \ \G description ... 28: 1.3 crook 29: \ The output is a file of entries that look like this: 30: \ make-doc [--prefix]-entry name stack-effect ) wordset [pronounciation] 1.1 anton 31: \ description 32: \ 33: \ (i.e., the entry is terminated by an empty line or the end-of-file) 34: 35: \ this stuff uses the same mechanism as etags.fs, i.e., the 36: \ documentation is generated during compilation using a deferred 37: \ HEADER. It should be possible to use this togeter with etags.fs. 38: 39: \ This is not very general. Input should come from stream files, 40: \ otherwise the results are unpredictable. It also does not detect 41: \ errors in the input (e.g., if there is something else on the 42: \ definition line) and reacts strangely to them. 43: 44: \ possible improvements: we could analyse the defining word and guess 45: \ the stack effect. This would be handy for variables. Unfortunately, 46: \ we have to look back in the input buffer; we cannot use the cfa 47: \ because it does not exist when header is called. 48: 49: \ This is ANS Forth with the following serious environmental 50: \ dependences: the variable LAST must contain a pointer to the last 51: \ header, NAME>STRING must convert that pointer to a string, and 52: \ HEADER must be a deferred word that is called to create the name. 53: 54: 55: r/w create-file throw value doc-file-id 56: \ contains the file-id of the documentation file 57: 58: s" \ automatically generated by makedoc.fs" doc-file-id write-line throw 59: 1.3 crook 60: : >fileCR ( c-addr u -- ) 61: doc-file-id write-line throw ; 62: : >file ( c-addr u -- ) 63: doc-file-id write-file throw ; 64: 1.1 anton 65: : \G ( -- ) 1.3 crook 66: source >in @ /string >fileCR 1.1 anton 67: source >in ! drop ; immediate 68: 69: : put-doc-entry ( -- ) 70: locals-list @ 0= \ not in a colon def, i.e., not a local name 71: last @ 0<> and \ not an anonymous (i.e. noname) header 72: if 1.3 crook 73: s" " >fileCR 74: s" make-doc " >file 1.2 pazsan 75: >in @ >r 76: [char] ( parse 2drop 77: [char] ) parse 78: [char] \ parse 2drop 79: >in @ 80: bl word dup c@ 81: IF 82: dup count 1- chars + c@ [char] - = 83: IF 1.3 crook 84: s" --" >file 85: count >file drop 1.2 pazsan 86: ELSE 87: drop >in ! 88: THEN 89: ELSE 90: drop >in ! 91: THEN 1.3 crook 92: last @ name>string >file 93: >file 94: s" )" >file 1.1 anton 95: POSTPONE \g 1.2 pazsan 96: r> >in ! 1.1 anton 97: endif ; 98: 99: : (doc-header) ( -- ) 100: defers header 101: put-doc-entry ; 102: 103: ' (doc-header) IS header | https://www.complang.tuwien.ac.at/cvsweb/cgi-bin/cvsweb/gforth/doc/makedoc.fs?annotate=1.6;f=h;only_with_tag=v0-6-1 | CC-MAIN-2021-49 | refinedweb | 531 | 75.81 |
This section documents all changes and bug fixes that have been applied in MySQL Cluster Manager 1.4.2 since the release of MySQL Cluster Manager version 1.4.1.
Functionality Added or Changed
Agent: To allow easy detection of an incomplete agent backup, an empty file named INCOMPLETE is created in the folder in which the backup is created when the
backup agentscommand begins, and is deleted after the backup is finished. The continuous existence of the file after the backup process is over indicates that the backup is incomplete. (Bug #25126866)
Agent: MySQL Cluster Manager can now recover automatically a failed mysqld node, as long as the data directory of the node is empty when recovery is attempted; if that is not the case, after cleaning up the data directory manually, users can now manually run
start process
--initialto rebuild the mysqld node's data directory. (Bug #18415446)
Agent: The
show statuscommand now reports progress when the new
--progressor
--progressbaroption is used.
Agent: A new command,
update process, imports a process back into the control of mcmd after it has lost track of the process's status due to different reasons (for example, it has been restarted manually outside of MySQL Cluster Manager). For more details, see the description for the command.
Agent: When a custom
FileSystemPathvalue was used for a data node, the
list backupsand
restore clustercommands failed, as the backup directory could not be found. (Bug #25549903)
Agent: In some situations, a certain mcmd agent took too long to process event messages that a synchronization timeout occurred among the agents. This was because the agent went into a mutex contention for file access, which this fix removes. (Bug #25462861)
Agent: The
collect logscommand reported success even if file transfers were incomplete. This fix adds checks for file transfer completion and reports any errors. (Bug #25436057)
Agent: An ndbmtd node sometimes (for example, at a rolling restart of the cluster) sent out a large amount of event messages, and it might take too long for an mcmd agent to process them that the agent lagged behind on its readiness for the next command, resulting in a synchronization timeout among the mcmd agents. This fix drastically reduced the amount of event messages sent out about an ndbmtd node, thus reducing the chance of a synchronization timeout under the situation. (Bug #25358050)
Agent: A management node failure might trigger mcmd to quit unexpectedly on Windows platforms. (Bug #25336594)
Agent: Multiple errors thrown by the
backup agents,
rotate log, and
change log-levelcommands could potentially overwrite each other, causing a lost of error information. (Bug #25134452)
Agent: The
collect logscommand hung when TCP connections could not be established between the agent that initiated the command and the other agents. This fix makes the command timeout after the situation persists for more than 30s. Also, a new mcmd option,
--copy-port, has been added, by which users can specify the TCP port number to be used for log copying. (Bug #25064313)
Agent: The
.mcmfile created by the
import config --dryruncommand sometimes have certain configuration settings missing from it. (Bug #24962848)
Agent: A
restore clustercommand would fail if MySQL Cluster Manager did not have write access to the
BackupDataDirof each data node. The unnecessary requirement has now been removed. (Bug #24763936)
Agent: If a
stop clusteror a
stop processcommand had failed, a restart on some of the processes might fail with the complaint from mcmd that those processes were already stopped, even if they were actually running. That also made it impossible to reconfigure those processes when
StopOnErrorwas true. This happened because the failed
stopcommand had left those processes' metadata in an incorrect state. With this fix, the process restart is allowed despite the value of
StopOnError. (Bug #24712504)
Agent: Hostnames referenced in the error messages returned by mcmd were always in lower case. With this fix, the hostname is always referred to as it is; moreover, mcmd now always refers to a hostname or the IP address used in creating the cluster. (Bug #21375132)
Agent: A
restore clustercommand hung, when an mcmd agent failed and the other agents kept waiting to receive messages from it. With the fix, the other agents detect the failure and return an error to the user. (Bug #16907088)
Agent: When a cluster was being started, if a data node failed shortly after it was started and mcmd was still in the process of starting an SQL node, even if the SQL node was started successfully at the end, mcmd might forever lose connection to the SQL node. It happened when the user
mcmdrequired for the mcmd agent did not get created on the SQL node. With this fix, the user
mcmdis always created on the SQL node despite a failure of the
start clustercommand. (Bug #13436550) | https://dev.mysql.com/doc/relnotes/mysql-cluster-manager/1.4/en/mcm-news-1-4-2.html | CC-MAIN-2017-13 | refinedweb | 800 | 57 |
#include <OSLindoSolver.h>
Inheritance diagram for LindoSolver:
Definition at line 50 of file OSLindoSolver.h.
the LindoSolver class constructor
the LindoSolver class destructor
solve results in an instance being read into the Knitro data structrues and optimized
Implements DefaultSolver.
buildSolverInstance is a virtual function -- the actual solvers will implement their own solve method -- the solver instance is the instance the individual solver sees in its api
Implements DefaultSolver.
invoke the Lindo API solver
read the OSiL instance variables and put these into the LINDO API variables
read the OSiL instance constraints and put these into the LINDO API constraints
create the LINDO environment and read the problem into the internal LINDO data structures
LINDO does not handle constraints with upper and lower bounds this method is part of kludge where we add a new variable to handle the bounds.
read the quadratic terms in the model
read the nonlinear terms in the model
use this for debugging, print out the instance that the solver thinks it has and compare this with the OSiL file
Lindo's generalized error Reporting function.
m_osilreader is an OSiLReader object used to create an osinstance from an osil string if needed
Definition at line 124 of file OSLindoSolver.h.
declare an instance of the LINDO environment object
Definition at line 138 of file OSLindoSolver.h.
declare an instance of the LINDO model object
Definition at line 141 of file OSLindoSolver.h.
m_iErrorCode is a variable for LINDO error codes
Definition at line 144 of file OSLindoSolver.h.
because LINDO API does not take row ranges we need some extra suff m_miSlackIdx indexes the rows that get additional slack variable
Definition at line 148 of file OSLindoSolver.h.
m_iNumberNewSlacks is the number of slack variables to add
Definition at line 151 of file OSLindoSolver.h.
m_mdRhsValue is used to the store the constraint rhs if we do not use row upper and lower bounds
Definition at line 156 of file OSLindoSolver.h.
m_mcRowType - E for equality, L for less than, G for greater than -- used if we do not store rows using upper and lower bounds
Definition at line 161 of file OSLindoSolver.h.
m_mdLb holds an array of variable lower bounds.
Definition at line 166 of file OSLindoSolver.h.
m_mdUb holds an array of variable upper bounds.
Definition at line 171 of file OSLindoSolver.h.
m_mdLhs holds an array of the constraint lower bounds.
Definition at line 176 of file OSLindoSolver.h.
m_mdRhs holds an array of the constraint upper bounds.
Definition at line 181 of file OSLindoSolver.h.
m_mmcVarName holds an array of char arrays.
Definition at line 186 of file OSLindoSolver.h.
m_msVarName holds an array of variable std::string names.
Definition at line 191 of file OSLindoSolver.h.
m_msConName holds an array of constraint std::string names.
Definition at line 196 of file OSLindoSolver.h.
m_vcVarType holds an array of variable types (character), e.g.
'C' for continuous type, 'I' for integer type, 'B' for binary type, 'S' for std::string type).
Definition at line 202 of file OSLindoSolver.h.
m_mdObjConstant holds an array of objective function constants.
Definition at line 206 of file OSLindoSolver.h.
osrlwriter object used to write osrl from and OSResult object
Definition at line 209 of file OSLindoSolver.h. | http://www.coin-or.org/Doxygen/CoinAll/class_lindo_solver.html | crawl-003 | refinedweb | 542 | 55.54 |
How do I verify a
download?
This release fixes a few critical bugs and introduces the "now playing" feature window. This release, unlike other releases, only features the gmpc core; plugins and libmpd from... 0.19.0 are compatible
Avuton Olrich (2):
Modify version string to post-release version 0.19.95
gmpc version 0.19.1
Qball Cow (34):
GMPC 0.19.0 is the latest (at 19-09-09).
A. Klitzing (11):
Fix some issues with translation
Add possibility to press "enter" to create playlists
Revise mutex usage for metadata handling
Hotfix to German translation
Add 'search button' to artist-view in meta-data-browser
Use same order of stored playlists on context menu as in playlist-view
Add tooltip to similar artists in metadata-browser
Correct copy+paste mistake with Disc/Genre
Make 'Replace' translatable again in metadata-browser
Fix possible memory leak
Fix a seldom crasher if iter is NULL
Avuton Olrich (10):
Modify version string to post-release version 0.18.95
gmpc version 0.18.96
Modify version string to post-release version 0.18.97
gmpc version 0.18.98
Modify version string to post-release version 0.18.99
gmpc version 0.18.100
Modify version string to post-release version 0.18.101
gmpc version 0.18.102
Modify version string to post-release version 0.18.103
gmpc version 0.19.0
Mark Lee (3):
Fix typos.
Update i18n files.
Remove curl support.
Martijn Koedam (3):
Add some stuff creating bundle on mac
Merge branch 'master' of git://repo.or.cz/gmpc
Add missing file
Qball Cow (563):
Remove 'close unzip stream'
Remove 'close unzip stream'
On mmkey initialization show errors using playlist3_show_mes instead of popup windows
Remove printf in GmpcImage
Remove printf's from GmpcRating
[Bug: 2135] Remove check that does not print ':' when minute == 0
Change Directory -> Path and include filename
Add next song tooltip to the next button.
Remove paused from next song tooltip
Remove unused functions pl3_cover_art_button_pressed
Fix some warnings by casting string to (guchar *)
[GmpcEasyCommand] add seek support
Create GmpcPluginParent and access everything using that.
Add initial support for G:Object based plugins. Add vala test plugin.
Extend the example plugin
Add bug-information window (see bug 2147)
[BugInformation] Hide internal plugins, fix typos, fix warnings (compile/runtime)
[BugInformation] If connected include mpd information
Quick test to avoid crash when mpd crashes when fetching a block of playlist rows
[BugInformation] Style compilation flags, remove 2 non-interresting ones
Turn GmpcEasyCommnad into a GmpcPluginBase
Change namespace of new plugin
Remove unused cat-tree parametes (PL3_CAT_PRC and PL3_CAT_ICON_SIZE)
Mark more unused stuff deprecated
Change bug-information icon
Add Tool menu item
Move URL Fetcher to tool menu
Make tool_menu_update available to plugins
Fix some compile warnings
Create a gmpc-plugin.vapi file and use that.
Add an accelgroup to fullscreeninfo
Trying to fix library
[GmpcPlugin] Add default functions for get/set enabled and
Make gmpc-plugin.* depend on gmpc/libmpd vapi.
Turn playlist3-messages into a gobject plugin. (in C)
[Plugin] Fix the check if it is an internal plugin for GmpcPluginBase
Playlist3MessagePlugin updates
PluginClass: Remove global variable, and get parent_class dynamic
Playlist3MessagePlugin pull old global variables into Object, write wrapper for backwards compatibility
Remove a commented line
Add some (untested) code to load
Fixing loading new-type plugin
Remove printf's
Add get_translation_domain() to the plugin
Add translation_domain string to GmpcPluginBase class.
Update translations again
Pull 'playlist' out of playlist3-current-playlist
[PlayQueue] Turn this into a full fledged GmpcPluginBase Gobject.
Fix crasher\n
Move some internal plugin functions to plugin-internal.h
Include gmpc-plugin.h in plugin.h
Include runtime version
Add update_languages.sh script that runs intltool-date. don't translation gmpc --version
Update some doc.
Update translations from launchpad
Fix support for having no working NLS
Use gnome's autogen.sh
Add i18n header to gmpc-mpddata-treeview
add dummy
Try to determine ui path from XDG_PATHS
Try to determine icon path from XDG_PATHS
Try to use XDG dir on windows
Windows does not like default fallback encoding used by g_convert_*, use - instead
Revert to g_filename_from_utf8, if that fails, fallback to g_convert_
Remove TreeSearchWidget
Remove trying to printf connect
GmpcPluginBase make translation_domain a weak reference.
Better error reporting (via GError) if a plugin fails to load
Don't use glib 2.18 function when glib is older.
fix stupid check
Fix compile warning.. (const gchar ** to const gchar * const *)
fix compile warning in vala generated file
Fix compile warning.. (const gchar ** to const gchar * const *)
Fix compile warning
Wild shot in the dark at mixed sync/async downloader
Small fix
lower automake to 1.7
updates
Breaking more stuff
Fixing small things
Fix some scaling
failing
Comment the code a bit
Extra debug
Quick and dirty fix for broken headers
Keep thread around, instead off spawning it constantly
Add some m4 files (testing)
Fix 2 typos in configure.ac
add danish translation
[Configure] make NLS required
Make a somewhat working cover selector
Updates
[MetaData] Validate iter after moving to next entry
[Gmpc.MetaData.get_list] Allow cancelling off the query.
[ValaTestPlugin] Allow editing of artist image, include extra info
Add function to make vala wrapper happy (it cannot take a goffset (used by libsoup))
[GmpcTestPlugin] Don't destroy windows before all entries are cancelled
First cancel queries, then removes current downloads
Allow user to change query
Add option to attach user_data to GEADAsyncHandler
Give the right FETCHING signal
Remove qlib
Fallback for not loading stylized cover
Add fallthrough for loading images
Update some translation stuff
Fix compile warnings, error checking and more
Make query button sensitive again if all queries + downloads are done
UI improvements to the cover-selector gui
Avoid crash on --clean-cover-db
show progress when setting cover
Reduce compile warnings
Remove threading from metadata system
Only query enabled plugins
Remove locking from config system.
Add the code for lyric selector
If easy_download fails, don't hang metadata fetching.
Remove printf's
Deprecate old get_image function
Delete by id again, instead off position
[Bug:2198] Color client widgets (recursively) correctly. (draw background as STATE_SELECTED, so set fg and text to STATE_SELECTED color too)
Align text to the left and top
[Bug:2193] Fix search-as-you-type in file browser
[GmpcTestPlugin] Change alignment
avoid unneeded style-sets
Fix header coloring less cpu intensive
[CurrentPlaylist] Fix missing ! in crop function
Allow user to select biography and album info in metadata selector
[bug:2205] Set "Gnome Music Player Client" tooltip on the GtkStatusIcon
[bug:2205] Destroy notification when gmpc disconnects.
Don't try to copy NULL value.
Another test-fix
Add MetaData object plus creation, copy and destruction functions
Add some (incomplete) vala bindings for MetaData
Add some (incomplete) vala bindings for MetaData (fix return types)
Make the test-plugin use the MetaData object
Correction interper MetaData fields.
Wrap text in gmpc-test-plugin
Make metadata fetching use MetaData internally
Add extra asserts
Add a .gitignore file.
Add plugin-internal.h to EXTRA_DIST
Make gob build system more robust
Fix password dialog checkbox, don't disconnect when it is hit. update available tags when permission changes
Don't update tags when no combobox available
Don't send password, libmpd will do it.
Fix passing right uri to downloader
Fix passing right uri to downloader
First try compile time path. Then, one by one, try looking for the dir in xdg data dir, like: <xdg-data-dir>/gmpc/icons/
If volume is -1, disable volume control
Add help support to GmpcEasyCommand
Add a --with-extra-version= option, to set revision manually
Add easy-command command list to help->help easy command
Make proxy set code read the correct config values.
implement consume and single mode.
Make consume/single insensitive when not supported
[GmpcEasyCommand] Add crossfade and output enable/disable
[GmpcEasyCommand] Made list sortable, and enable search-as-you-type
[Bug:2236] Add EasyCommand: Stop after current song.
[Bug:2237] Add EasyCommand: Repeat current song.
[Bug:2223] Add EasyCommand: Crop current song.
GmpcEasyCommand close easy-command window when looses focus
[Bug:2240] Add update database command.
[Bug:2241] Support PLUGIN_DIR envioronment
Try to make plugin data path function more robust
If copy paste, copy paste wisely.
Update advanced-search regex on connect and permission change
Add help message to multimedia bind preferences pane
Update translations
Deprecate and remove the temporary (get_uris) api, fix markup bug in test-plugin
Add right mouse entries for metadata editor.
Fix wrong warning
[GmpcMetaTextView] Add support for (inline) editing of the lyric/album info/biography
always default to non-editable
Allow search-and-replace string in weblinks format, some sites require
Fix build
Fix build
Let expose fallthrough
Show Next: <song> in notification.
Italic the next song song text
[Notification] Show number of remaining songs instead of cover when in consume mode and less then 100 songs left
Remove debug printf that could print an out-of-bound value.
Put remaining songs number in overlay over image.
[Bug:2270] Allow seeking in tooltip.
[Bug:2269] Reshow buttons if visible.
Store music directory per profile
Make url_fetcher support entering of mpd supported url-handlers
Try to be more precise with getting extension
Remove printf
Fix several unitialized pointers and small memory leaks?
Remove the blocking easy-download api
Also support 'local' files in url_fetcher
Use url_fetcher for parsing drag and drop urls
Reset timeout on seek
use g_fopen() instead of fopen().
[PlayQueue] reduce search timeout to 250ms.
Add test for config system.
Extend the config test
Fix showing of extension. || -> &&
Add a scripts folder
Add gmpc-favorites, test version
GmpcFavorite: Remove visible window from event box, Fix possible translation errors. Add to Metadata Browser
[GmpcFavorites] change favorite -> Favorite
[GmpcFavorites] Do some nice-ish highlight effects
[GmpcFavorites] Remove printfs
Makefile: fixing pointless builds.
[GmpcFavorites] small fix
Add a GmpcMpdDataModel test.
Extend the test
Update so it works with newer vala. (still needs patched vala)
Fix many compile warning and change read to the correct fread
Fix param type (char * -> const char *) in plugin_load()
Fix overlapping entry over buttons
Vala updates
Use icons in entry when using Gtk 2.16 or up
Update translations from launchpad and fix make distcheck
Avoid having process_itterate called one time to often, add printing of debug messages
Make the gmpc-favorites hide when not playing. comment the code
Rewrite gmpc-liststore-sort.gob to gmpc-liststore-sort.vala
Add GtkTransition.h to all vala files and lower gtk dependency
dos2unix gtktransition.h
Make all vala use gtktransition.h except gmpc-plugin
Change gmpc-connection.gob to gmpc-connection.vala
Remove gmpc-signals.
Change gmpc_image to gmpc-image
Change gmpc_rating to gmpc-rating
Show the cached result in the metadata browser
Add missing vala files.
Similar song with less round-trips to mpd and case insensitive
Also include artists not in the db
Remove duplicate code
Remove false comment
Initial implementation of MetaData based metadata_cache
Fix crasher
Reverse the list, so it comes out in the order stored.
-add MEAT_DATA_SIMILAR to MetaDataType
Fix overlap in define value and update vapi file
Remove lock again :-P
[Bug:2296] Check before albumartist if it is suported
Using sqlite as metadata database
Remove old code
Use MetaData throughout mpd, not the old path stuff
Fix not showing of metadata in GmpcMetaImage if MetaDataResult == UNAVAILABLE and using delayed show
Correctly convert callbacks to MetaData
Make playlist3-metadata-browser similar song view support both text_vector as text_list
Extra error reporting when loading preferences-mmkeys ui
Remove the requires field from preferences-mmkeys.ui
use transation to insert lists
Validate keys as utf-8 before storing/loading values
try to fix the match_data function and stop after giving unavailable signal
GmpcMetaTextView: if editing a text file store result inside the db.. support text files from db
GmpcMEtaTExtView: support DATA_CONTENT_HTML, and stip tags. (needs work? html parse?)
Don't try to look in cache with to little information
Don't try to set cache with to little information
fix crasher because MetaData is not set
Add gmpc-connection.h to install
Make gmpc-text-plugin pass MetaData objects instead of path strings
Fix Crasher when loading gif file. (vala set length to -1 instead of real length)
Match signedness of type
Try to fix crasher from 2312
Re-introduce the --clean-cover-db
Cleanup gmpc-clicklabel
More GmpcClickLabel cleanup
Document and 'Seal' GmpcClickLabel
Cleanup GmpcStatsLabel
Use g_log_ for meta_data_cache debugging
Include copyright notice in metadata_cache.c/h
Remove exposing of internals of gmpcPluginBase from metadata.c
Include sqlite3 (runtime/compile time) version in bug information
Add function --bug-information to commandline, showing the dialog
Remove 'bug-information' information from --version
Use g_option_* instead of custom commandline parser
Remove unneeded wrapper function
Add meta_data_is_* functions
Translate old 'debug-level' to g_log level and filter out g_log messages
Don't reset metadata plugin cound when --disable-plugins is used
In automatic metadata fetching store everything, beside online uri, in the MetaDataCache
Remove false todo entry in file
Remove extra {}
BugInformation: Don't show 'Plugin' head when no plugin is loaded
Fix large-ish memory leak in advanced-search
Add copyright notice to advanced_search.c/h
Fix compile warnings in sm.c caused by gcc marking define'd strings as const char * instead of char *
Fix compile warning in mmkeys (C90 comp.)
Fix compile warning in main.c
Fix compile warnings metadata_cache
Fix compile warnings metadata.c
Fix gmpc-easy-download compile warnings
[MetaDataCache] use meta_data_is_* wrapper
Fix wrong detection of same album in info2_fill_album_view
Fixing a one-off buffer overflow.
Add --log-filter options, allowing you to show debug output of selected domains.
Fix small leak caused by invalid gdk vapi
Try to avoid extra separators
Make path/directory clickable in MetaData Browser. A click will jump to the dir in the directory browser
Use clicked signal on GmpcClickLabel instead of low-level button press event
MetaDataBrowser: make directory label on AlbumButton also click-able
FileBrowser: when opening @ path center the selected row
gmpc_get_metadata_filename call with the edited version
Try to avoid false updates
fail
debug output
blaat
Re-indent the stupid metadata.c file. using vim.
Remove unused meta_commands
Quick printf to track creation/destruction of meta_thread_data
Move from AsyncQueue to Queue
cleanup and comment what is happening
Implement a quick and dirty gmpc-easy-command test.
Improving the gmpc-easy-download test.
Extra output
Fix MpdDataModel test
Mark 'new-style' internal plugins as internal
Rename the preferences add/remove in the GmpcPluginPreferencesIface and remove preferences pane in test plugin
[Tag2 Browser] When a column is added always reset the whole browser
[Tag2Browser] Fix several problems with showing cover art
Try to improve correctness gmpc_mpddata_model_set_mpd_data_slow() might fix samtihen issue?
Don't check albumartist if tag not supported
Don't store empty images
broken and untested quick and dirty new gmpc_mpddata_set_mpd_data_slow function
[MetaData] fix race if new item was added between process_itterate() removing last item and the last g_idle_add was handled
Merge branch 'master' of git://repo.or.cz/gmpc
Fix compile warnings and debug output
Do sqlite integrity check on startup and set synchronous mode to normal
Set synchronous off
Fix song-link double calling open_uri and wrong escaping.
[GmpcMpdDataModel] try to fix samtihen crasher
[GmpcMpdDataModel] Make the images list available at the time of row insertion.
Add GmpcMetaDataPrefetcher.
cleanup
GmpcEasyDownloader: Only store data when http status is 200. if status changes clear out previous stored data and reset zlib
Grab entry box, if available
Grab focus to text entry
sync
Fix compilation using strict(er) rules
[GmpcMetaImage] Add 'scale-up' property
Export GmpcConnection to plugins, needed to use the GObject based plugin api
Remove the ugly combo from the tag browser
vpane->hpane and iconview -> treeview
Set rules hint on playlist list
Change layout tag browser
[TagBrowser] make pref and tag browser be in sync again
Add cancel button
Add --spawn to gmpc-remote (expiremental)
Update gmpc translation
Add more log domains.
Add g_log to sm.c
Take 100ms extra before trying to hide to tray
Bump timeout from 100 -250ms
remove printf's
Remove printf's from tag browser
Make GmpcPluginMetaDataIface work
Fix vala binding
[PlayQueue] Move quick filter to the bottom.
[PlayQueue] Remove double focus
[PlayQueue] Make pressing the Browser key focus the tree (most cases F1)
Make entry in 'new playlist dialog' activate default widget (save)
Don't print seconds in total time. Don't show % counted
Add FastForward and Rewind keybinding, and fix catching keys when numlock is enabled
Correction on previous commit
Remove printf
KEy up/down on filter entry makes treeview grab focus
Add 1/8 done metadata2 plugin
[MetaData2] Dump most ready-to-use widgets into place
Add more information, put large texts into a more/less widget
Make the more/less behave more correct.
Implement the 2nd click is unselect.
Also show songs when only artist selected
Add filter entries
Workaround GTK warning on exit
[MetaData2] Add add/replace play buttons
[MetaData2] If no item selected, show current playing song.
Add favored to metadata browser
trying to fix
Add more sizes off the application icon.
[MetaDataBrowser2] Store position in category tree
[MetaDataBrowser2] Use this.get_name() instead of hardcoded name in config category
[MetaData2] Do the same filter hiding as in the tag browser
[MetaData2] reset filters on reload
[Playlist] Re-order the way the favored button is added to header, so it stays on the right position after collapsing view
Increase timeout on every failed try
[MetaData2] Add Rating.
Small binding update
Add room for more metadata types.
[MetaData2] Add option to jump to artist X.
[MetaData2] Make similar artist button
Add META_SONG_GUITAR_TAB,, make it known to the metadata_cache
Add support for guitar tabs in the metadata selector
Fix metadata match function and add guitar tab to metadata2
Use monospace font for text-view
Show correct fetching message for guitar tabs
Add Now playing browser, remove old metadata browser. Add glue code to make old api use new metadata browser
Remove the old metadata browser source file
[Now Playing] show logo instead of white screen
Print unknown instead of (null)
Add similar song, db query in idle time
Add menu to similar song
Possible fix 2368 by splitting in 2 columns
[2370] Fix for bug.
Add tool menu entry with ctrl-i keybinding
[GmpcMetaWatcher] Fix signal prototyping. (bug 2374)
[MetaData2] Sort the album list on the left by date
Show date in album list
Try to add support for automake-1.11 in gnome-autogen script.
[Metadata2] Use albumartist tag to find all songs in album (when available)
Adding song list to album view.
[MetaData2] Add button to open directory in file browser
[MetaData2] Add link to find browser for searching songs with same title
[MetaData2] Add artist/album treeview context menu for add/replace
Make vala files compile with vala 0.7.3
Fix some more vala compile issues/warnings
Allow dragging of slider
Metadata Browser 2 -> Metadata Browser
Only use monospace in guitar-tab
Add right mouse menu and row-activate in album-view song list
Select song when clicked on header.
Add missing include
[Metadata2] Make the scrolled window follow the focus of the container it contains.
[Metadata2] Make labels selectable
[GmpcMetaTextView] Set curser at the beginning after filling text view
[Bug:2388] Fixing no border on treeview tooltip.
[Bug:2386] Added page-up/page-down keys.
[MetaImage] Make tooltip size slightly larger
[MetaImage] set black border 6 pixel
[GmpcProgress] make update instant like totem.
use step increment and try to fix building on hardy
Add config flags for similar artist, album information, artist information, similar songs, lyrics and guitar-tabs
Add preferences pane that allows the user to disable metadata. Bug:2391
Add several sizes of the media-audiofile icon.
Remove old media-audiofile file.
Remove old metadata browser from potfiles.in
Remove Encoding=UTF-8 from gmpc.desktop as it is implicit now
Make gmpc.desktop pass desktop-file-validate
[MetadataBrowser2] Remove lots of duplicate code
Allready -> already.
Infinished widget for tooltips on tag treeviews. bug 2389
Add tooltips to tag browser/metadata browser
Remove printf
Obey the show-songlist tooltip setting for GmpcMpdDataTreeViewTooltip
Trying to fix some scrolling crap
Export the gmpc-mpddata-treeview-tooltip header for plugins
[Gmpc.Widget.More] Remember last state as set by unique_id
[GmpcMetaDataBrowser2] Don't follow focus, causes odd behauviour
Allow double-click to jump to position.
Small updates
Make the play_queue_plugin take a uid as param.
[GmpcMetaTextView] Pressing Escape cancels the editing
Move the Server menu entry mnemonic to the r. trying to avoid collision
Add support for the (in memory) api of libxspf
Sync paned position between file, playlist editor, metadata and tag browser
change url_fetcher -> url-fetcher
Remove edit_markup
advanced_search -> advanced-search
change metadata_cache -> metadata-cache
Add initial eggsmclient support.
Remove old sm stuff
Make eggsmclient work on osx?
Connect quit signal to session manager
Remove old session-manager hints
[Bug:2403] Possible fix for non-consistent context menu behauviour
Fix for bug 2404, add right context-menu entries
Fix for bug report 2403b
Move play_path from Gmpc.Misc -> Gmpc.MpdInteraction
Test implementation forward/back buttons: Bug 2402
Fix small thing
Work around the fact that older gtk do not have gtk_menu_item_set_label
Reverse order of history list as requested in bug:2402
[Metadata2] Add artist/album buttons for quicker navigation
[Metadata2::History] Do pointer compare instead of content compare
Add some test code to have anice tooltip on tray-icon. (thx to malept)
Show only the popup, not the real tooltip too
Remove eggtrayicon.
Show the notification dialog on mouse over on the tray-icon (Gtk 2.16 and up), even when disabled
[MetadataSelection] change Set cover -> _Set
Try to improve similar artist display time
Update to newer vala
[TrayIcon2] Fix closing #endif using to much code
Fix small compile warning
Line-out the buttons on the right in the metadata browser
Remove some empty rows
Generate C code from previous commit (thx MiserySalin)
Bug:2315 Remove controls in now playing
Pack the widgets in the main interface slightly different
Trying to fix borders
Trying to fix borders (again)
Merge branch 'master' into 0.18.1
[TrayIcon] Don't set volume on scroll event when mpd either does not allow it, or mixer does not support it.
Make the remove_duplicate more bulletproof. first compare song->file
Bug:2424 Fix tag browser
Merge branch 'master' of git://repo.or.cz/gmpc
Remove extra copy paste crap from the license.
[MetaData2] Update the browser if db gets reloaded
Only show the text in the popup if connected
On mouse over always position the notify at the tray-icon
Make GDK_Menu work in GmpcMpdDataTreeView
Add ar, th translation and update other translations.
use AM_MAINTAINER_MODE, fix compile warnings.
A Hack to add a slow delay to showing the tooltip (workaround for gtk but 516130)
Trying to improve timeout
Sort before adding
Add keybinding metadata2 (and go menu entry) and fix icon now-playing
Remove duplicate code, allow metadata/now playing to be disabled.
Add right-mouse play entry to metadata2::albumview song list. (first item context menu should match double click)
Add single/consume to easy command window.
[GmpcEasyCommand] Remove printfs and unused code
EasyCommand: Make internal variable private, add quick description.
[MetaData2] Add description
Try to speed up Similar ARtist view.
Add a status-icon-hbox hbox to the glade file
Add main_window_add_status_icon function and repeat/random implementation
Add stock_repeat,stock_shuffle icon so no dependency on gnome icon theme is added.
Increase contrast, unref pixbuf
Small cleanup
Don't create artist 'buttons' you aren't going to use. Limit results to 30
Small test with no artist image
Adding a small metadata_cache test program.
Add extra entry
Improve the artist/album matching algorithm used by similar artist. (qsort(m) + O(n) instead of O(n*m). Seems faster..
Small update
Fix menu key when first item is selected.
Remove empty files
Remove printfs
Add --fullscreen commandline option
Fixing a memory leak in vala
Fix a tiny memory leak
Add vallgrind sh
Fix for bug 2445 and change binding for better C generation.
Update translations from launchpad
Translate plugin title in preferences menu
Only use g_dgettext with glib 2.18
Don't colorshift but set image sensitive/insensitive
Move wrongly placed mpd_freeSong()
Use next/previous button on the mouse to go forward/back in metadata browser 2
Move updating icon to the status_icon bar.
Disable all multimedia keybindings by default (fresh install)
Add support for showing last modified entry in song info.
Remove the sub Makefiles on src/
Fix compile warnings
Make gcc more happy
Adjust for new vala
Also export gmpc-profiles.h again.
Use casefold instead of down.
Trying to fix make distcheck
Trying to fix stuff for win32
Small vapi update
Update translations
[Bug:2471] Re-hovering the slider should remove old tooltip.
remove printfs
Move log handler up so all logs are catched by it
Add + and - to the more/less widget.
Merge branch 'master' of git://repo.or.cz/gmpc
Bug:2473 Fitt gmpc to Fitt's law.
Remove mtime
Remove unneeded hack for windows
Make GmpcDataModel test use g_test framework.
Fix crasher when doing right click on artist in metadata browser.
Include vala/vapi files in make dist.
[TrayIcon] Fix bug 2481
Remove printfs and fix vala files
Grab focus to entry box when switching to search browser
[url fetcher] Close the dialog after adding a non-http type
Also close when parsing a local file.
[url-fetcher] Allow parse_uri function to stop loop. (hack need real fix)
Change stupid check order
User (1):
Abort when no working gettext implementation is found
qball (2):
Add first version of the pane-size-group
Also add files to panedsizegroup | https://launchpad.net/gmpc/+download | CC-MAIN-2016-18 | refinedweb | 4,258 | 50.77 |
Character datatypes are used to hold only 1 byte of character. It holds only one character in a variable. But we need to have more features from this character datatype as we have words / sentences to be used in the programs. In such cases we create array of characters to hold the word / string values and add null character ‘\0’ to indicate the end of the string.
Suppose we have a string ‘C Pointer to be stored in a variable in the program. Then we create an array of character to hold this value. Hence we declare and initialize it as follows:
char chrString [] = {‘C’,’ ’,’P ’,’o ’,’i ’,’n ’,’t ’,’e ’,’r ’,’s’,’\0’};
OR
char chrString [] = “C Pointers”; // Double quotes are used instead of above representation
We can observe from above declaration and diagram that it is also an array like any other array that we have already discussed. Hence we can have pointers to these character arrays too like other array pointers. When the pointers are used for character array or strings, then it is called as string pointers. It works similar to any other array pointers. When we increment or decrement string pointers, it increments or decrements the address by 1 byte.
Let us try to understand string pointer using a program. Consider the program below. chrString and chrNewStr are the two strings. First string is initialized to ‘C Pointers’ where as second string is not. String Pointers chrPtr and chrNewPtr are initialized to chrString and chrNewString respectively. Initially chrPtr will point to the first character of the string chrString. In the while loop below we can see that each character pointed by the chrPtr (‘C Pointers’) is compared with NULL and loop is executed till the end – till null ‘\0’ is encountered. Inside the loop, each character of the pointer is displayed and the pointer is incremented by 1 to point to next character. In the next step, the each character is copied to another pointer chrNewPtr. At the same time, both the pointers are incremented to point to next character. Here we can see increment operator is used along with ‘*’, i.e.;*chrPtr++. The compiler will split it as *chrPtr and chrPtr++; which means it will first assign the value pointed by current address in chrPtr and then it will be incremented to point to next address. Hence it copies character by character to another pointer and is not overwritten nor is same value copied. When chrPtr reaches its end, it encounters ‘\0’. Hence the while loop terminates without copying ‘\0’ to new pointer. Hence we explicitly terminate the new string by assigning ‘\0’ at the end. Thus when we print the value of new string, chrNewStr, it gets the value copied to chrNewPtr pointer. Hence it displays the copied value.
#include <stdio.h> int main() { char chrString[] = "C Pointers"; char chrNewStr[20]; char *chrPtr; char *chrNewPtr; chrPtr = chrString; // Pointer is assigned to point at the beginning of character array chrString chrNewPtr = chrNewStr; //Assign pointer chrNewPtr to point to string chrNewStr printf("String value pointed by pointer is :"); while (*chrPtr!= '\0') { printf("%c", *chrPtr); // displays the value pointed by pointer one by one *chrNewPtr++ = *chrPtr++; // copies character by character to new pointer } *chrNewPtr = '\0'; printf("New copied string pointer is :"); puts(chrNewStr); return 0; } | https://www.tutorialcup.com/cprogramming/string-pointers.htm | CC-MAIN-2021-39 | refinedweb | 549 | 62.27 |
ASF Bugzilla – Bug 49273
Font.getCharSet return byte is error
Last modified: 2010-05-25 12:26:06 UTC
Sample XSSFont.getCharSet:
public byte getCharSet() {
CTIntProperty charset = _ctFont.sizeOfCharsetArray() == 0 ? null : _ctFont.getCharsetArray(0);
int val = charset == null ? FontCharset.ANSI.getValue() : FontCharset.valueOf(charset.getVal()).getValue();
return (byte)val;
}
//When val great 127,then (byte)val is negative!
//So return type is should change to int
Any chance you could upload a file with a character set outside the 0-127 range? That can then be used as part of a unit test for the change.
(In reply to comment #1)
> Any chance you could upload a file with a character set outside the 0-127
> range? That can then be used as part of a unit test for the change.
ok,I upload a xlsx file.When character set is GB2312(character set value is 134),Scene is occur!
Created attachment 25434 [details]
It is have GB2312 charact set
Thanks for the sample file. Fix and unit test added in r948089. | https://bz.apache.org/bugzilla/show_bug.cgi?id=49273 | CC-MAIN-2016-40 | refinedweb | 172 | 68.36 |
Mike Diehl had a recent blog post about debugging Windows Services. As I've been doing quite a bit of this lately, I thought I might jump in with some more information on Windows Services and the fun that is debugging them.
Debugging Service Startup
When a Windows Service is installed into the Service Control Manager, it doesn't start running until it's either started manually or if the installer StartType property is set to "Automatic" then after the system reboots. What this means to your debugging is that you can't simply install the service and attach the Visual Studio debugger to the process as there isn't one to attach to until after you start the service. However, once you start the service if you have a bug such as an exception in the service's initialization you won't get the debugger attached to the process before it's too late. So then, how do you debug the service class' initalization? Using the System.Diagnostics.Debugger.Lauch() method.
{
#if
System.Diagnostics.Debugger.Launch();
#endif ...
This method pops up the following screen asking you which instance of the debugger it should use to debug the application.
Note that I have placed the Debugger.Launch method call inside a "#if DEBUG" compiler directive. DEBUG is a predefined directive that is automatically added when the application is compiled in Debug mode. Therefore, while I am working on the application the Debugger.Launch method will be called, but when I switch to Release mode the C# compiler will skip that command. This will keep you from having to remember to remove all of your Debug code (not that you shouldn't be doing that anyway).
Debugging After Startup
After the service has intialized and the OnStart override has been executed the service will begin its work. If you've used the method listed above to start the Debugger when the service starts up you can then create breakpoints in Visual Studio or you can put Debugger.Break() methods into your code where you want the debugger to stop code execution.
You can however choose to debug a service that is already running, by attaching the Visual Studio Debugger to the process. Click on the Debug menu option and select "Processes". This will bring up the following window listing the processes currently running on the machine.
Select the process you want to debug and hit the 'Attach..." button. The next window asks what types of programs you want to debug. Make sure the "Common Language Runtime" option is checked and hit OK. You are now debugging that process. If the EXE is compiled in Debug mode and the PDB file is in the same directory as the EXE, you should see the source code for your service. Just set your breakpoints and you're off and debugging.
Recompiling The Service
When the Service Control Manager tells the service to stop, the process for the service should finish up any work and end gracefully. As long as this is happening and no threads are left running, you should be able to simply recompile your service in place without reinstalling it. However, if you do leave any residue running Visual Studio will give a build error saying that the EXE file cannot be copied because access is denied, file in use by another process. This is a design issue so if you find that after stopping your service you still cannot access the EXE file, you should debug the application to make sure you have cleaned up all of the resources and threads.
Execution Permissions
I tested every version of the Account property settings and no setting would prevent me from debugging the application. Therefore, you should not need to add any users or groups to the "Debugger Users" group on your machine. My testing on this was pretty quick though and so there could be some instances where this might be required.
Hope this information helps in your Windows Service Debugging
I've been working on my "super duper mucho excellente" windows service project and the obvious questions
If you are taking time out to read this post, you have probably experienced the pain of debugging windows
Pingback from dave-smith.net » Windows Service Development
PLR articles is another method of marketing your products through outsourcing
Most large rental truck fleets have offices in most major cities as well as larger size towns, something most of the large professional moving companies don t have. This makes it much easier to find, deal with, rent and finally return the rental truck
Lately I have been trying to find a good and simple way if debugging a Windows Service Project most ways | http://weblogs.asp.net/paulballard/archive/2005/07/12/419175.aspx | crawl-002 | refinedweb | 788 | 58.32 |
Aug 28, 2011 04:34 PM|Doggy8088|LINK
Hi,
I just saw on this issue on Stackoverflow: . The web.config's httpRuntime executionTimeout is not working when using ASP.NET MVC.
I also tested on ASP.NET MVC 2 and ASP.NET MVC 3 website on IIS6 and IIS7 and that is all the same result. It seems like ASP.NET MVC "forgot" to implement a executionTimeout feature. Does anyone who can confirm this?
Thanks!
Sep 02, 2011 11:42 AM|imran_ku07|LINK
This is due to the fact that timeout state in ASP.NET MVC is off due to various reasons.
So just adding this before your complex tasks will make executionTimeout work in ASP.NET MVC as well,
System.Web.HttpContext.Current.GetType().GetField("_timeoutState", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic).SetValue(System.Web.HttpContext.Current, 1);
But this will not work in Medium trust application. Also see this thread.
Edit: Also note that the timer is fired in every 15 seconds.
Sep 03, 2011 01:03 PM|Doggy8088|LINK
Hi Imran,
Can you tell some or one of the reasons? I couldn't figure it out.
Thanks.
Sep 03, 2011 03:13 PM|imran_ku07|LINK
Doggy8088
Hi Imran,
Can you tell some or one of the reasons? I couldn't figure it out.
Thanks.
<httpRuntime executionTimeout="1"/> <compilation debug="false" targetFramework="4.0"> <system.webServer> <handlers> <add verb="*" path="*.sample" name="HelloWorldHandler" type="WebFormViewWithRazorLayout.Controllers.HelloWorldAsyncHandler"/> </handlers> namespace WebFormViewWithRazorLayout.Controllers { public) { Thread.Sleep(20000);) { Thread.Sleep(20000); } } class AsynchOperation : IAsyncResult {; } }); } }
Run this application. You will not get any request timeout exception.
Now just replace IHttpAsyncHandler with IHttpHandler, you will get a request timeout exception.
Another reason (which may be not as guinine) is that MVC is built with testability in mind. So if async timeout is become on, than you can easily end the request by calling Response.End, which may defeat the purpose of MVC. BTW, this is just my weak openion.
All-Star
15531 Points
Microsoft
Moderator
Sep 08, 2011 06:09 PM|ricka6|LINK
Execution timeout is unsupported in asynchronous ASP.NET pipelines (which is what MVC is).
We're looking into addressing this in MVC 4.
Sep 09, 2011 11:33 AM|Doggy8088|LINK
Thanks!
All-Star
49988 Points
Sep 09, 2011 02:53 PM|bruce (sqlwork.com)|LINK
the techicial reason timeout don't work with async handlers is pretty easy to understand. timeout are done with a watchdog timer (either async or seperate thread). when the timeout fires, and the request is still running how do you stop it? with a standard handler you just do a response.end which kills the long running thread and return response to client. with an async handler, you can not kill the thread because it may be processing another request (the point of using async request). the best you could do is to mark the thread as suspect, and kill it the next time its returned to the pool or was running the timeout request.
Dec 10, 2011 02:18 AM|imran_ku07|LINK
DalSOft
Please can you confirm if this has been fixed in MVC 4.
MVC 4 has not been released yet. MVC 4 still in a preview stage and at this stage it has not been fixed.
8 replies
Last post Dec 10, 2011 02:18 AM by imran_ku07 | http://forums.asp.net/t/1715081.aspx | CC-MAIN-2014-42 | refinedweb | 559 | 61.02 |
JSON is easy to work with and has become the standard data format for virtually everything. Although originally derived from the JavaScript scripting language, JSON is now a language-independent data format and code for parsing and generating JSON data is readily available in many programming languages.
At Stackify, we use JSON extensively for REST APIs, serializing messages to queues, and much more. We have compiled a list of some common JSON performance tips. While we use .NET for most of our services, most of these tips apply to other programming languages as well.
1. You may need multiple JSON libraries for optimal performance and features
In ASP.NET the most popular JSON library is Json.NET (Newtonsoft). But ServiceStack, FastJsonParser (System.Text.Json) and even the built in DataContractJavascriptSerializer may be faster or provide specific features you may need depending on the scenario.
This is based on my own testing and I encourage you to do the same. If you do a lot of parsing and really care about performance, FastJsonParser is a lot faster than anything else I have tried. I highly recommend it. Here are my results from doing some simple benchmarks from a test app (View on GitHub).
Fastest serializer: ServiceStack
Fastest parser: FastJsonParser
Overall most features and flexibility: Json.NET
I haven’t tested it myself but I have also heard good things about Jil which is designed entirely for speed by StackExchange’s team.
2. Use streams whenever possible
Most JSON parsing libraries can read straight from a stream instead of a string. This is a little more efficient and preferred where possible.
Improved Performance using JSON Streaming
3. Compress your JSON
Since JSON is just simple text, you can expect to get up to 90% compression. So use gzip wherever possible when communicating with your web services.
4. Avoid parsing JSON if you don’t need to
This may seem obvious, but it necessarily isn’t. For web apps that receive JSON and simply write it to a queue, database, or other storage, try not to ever parse the JSON if you can. When using something like ASP.NET Web API, don’t define your methods expecting specific classes as incoming data and instead read the post body so ASP.NET never parses the JSON.
For Stackify’s services we use header values for authentication, so in some scenarios, we never even need to analyze the body of the message. We can just queue it and let our background services do further validation of the data later.
[HttpPost] public async Task MyMethod() // no method parameters here! { //Read raw json as a string from the body of the HTTP post, and don’t parse it string results = await Request.Content.ReadAsStringAsync(); //Then write the data as a string to a queue or somewhere }
5. Serialize/Deserialize Larger vs Smaller JSON Objects
In some use cases, you may receive a large object array that you have to break up into smaller pieces. For example, at Stackify as part of our error & log management tool, we can receive some large JSON messages of log statements. We queue the log messages as they come in and there is a maximum message size for the queue. In the first version of our code, we were looping through the array and kept serializing one log messages at a time because the final output could only be up to a certain size to queue. We were able to do some optimization of this logic and it made a pretty significant difference in server CPU usage.
6. Use pre-defined typed classes
If at all possible, make sure you have a class that matches the JSON structure you are working with. Parsing generic JSON to a JSON.net JObject or generic dictionaries with FastJson is slower (~20%) than reading that data in to a defined class type. This is likely because a lot more meta data is tracked with the generic Json.NET’s JObject, JArray, JValue objects.
Newtonsoft.Json.JsonConvert.DeserializeObject<List<MyType>(jsonData); //faster with typed object Newtonsoft.Json.JsonConvert.DeserializeObject(jsonData); //slower with generic JObject result
7. Customize the Web API’s JSON Parser
By default Web API uses Json.NET. If you want to use a different one you can override it by making your own MediaTypeFormatter. In some scenarios you may also want to configure various special settings as well.
Learn how to use an alternate JSON serializer here.
Find info about Web API serialization settings here.
8. Don’t serialize all fields, null or default values
Check your JSON library settings to see how you can ignore specific fields, omit null values, etc. Most .NET libraries will use DataContract/DataMember attributes and settings.
Get Json.Net docs on the subject here.
9. Use shorter field names
Most libraries enable you to specify attributes on your classes to override the names of the fields as they are being serialized. This can allow you to make your field names much smaller when serialized but more human readable in your code. Using smaller field names can give you a 5-10% parsing performance boost and of course slightly smaller data packets being passed around.
Most libraries will honor DataMember attributes.
[DataContract] public class Monitor { [DataMember(Name = "id")] public int MonitorID { get; set; } }
10. Manual serialization or parsing could be faster… or slower
Some libraries, like Json.Net and ServiceStack have the ability to let you tailor the serialization and parsing as it occurs. They basically work like a tokenizer and read or write through the JSON one segment at a time. Depending on your use case it could be slower or faster to do this.
I experimented with using Json.Net and a JsonTextReader to improve JSON performance but found that it still didn’t come anywhere close to being as fast as the much easier to use FastJsonParser. This finding was pretty amazing to me.
11. Have you considered alternatives to JSON?
JSON isn’t the solution for everything. XML has gone out of favor as JSON has become the standard, but depending on your use case, it might still be a good fit for you, especially if you want to enforce a strong schema. Another option is BSON or MessagePack, which are types of binary-based object serialization. The only big downfall is they aren’t human readable or editable like JSON.
Here’s a good article about configuring Web API to support JSON, XML, and different XML settings:
Measuring JSON Performance Improvements
Isolated Testing
For basic testing, you can use Visual Studio’s built in performance analyzer with a simple console app. Grab a good sample of your JSON and do various serialize/deserialize tests tens of thousands of times in a loop and watch how long it takes, CPU, and memory usage.
View my benchmarking app on GitHub
Real World JSON Performance Testing
To measure real world impact of Stackify’s common JSON performance tips, you will want to track server CPU and page load times to compare before and after. You can use Retrace from Stackify to do this.
- | https://stackify.com/top-11-json-performance-usage-tips/ | CC-MAIN-2018-13 | refinedweb | 1,186 | 63.9 |
Parameter mixin for intensity normalization. More...
#include <vbl/vbl_ref_count.h>
#include <vbl/vbl_smart_ptr.h>
#include <vil/vil_image_view_base.h>
#include <vul/vul_timestamp.h>
#include <gevd/gevd_param_mixin.h>
Go to the source code of this file.
Parameter mixin for intensity normalization.
These parameters govern a linear normalization of intensity values from some arbitrary range to [0,1]. If the raw intensity range is the x-axis, and the normalized range is the y-axis, then two points, "high" and "low", are given. A line is fit to these two points, and the two x-coordinates where y==0 and y==1 are the intensity minimum and maximum clip points, imin_ and imax_. The context is that the y-coordinates of high and low points are found by histogramming the source image, and picking the (say) 5% and 95% points.
The defaults are interpreted by the normalize() routine as a no-op: no normalization is performed.
Modifications: MPP Mar 2003, Ported to VXL
Definition in file vifa_norm_params.h.
Definition at line 101 of file vifa_norm_params.h. | http://public.kitware.com/vxl/doc/development/contrib/gel/vifa/html/vifa__norm__params_8h.html | crawl-003 | refinedweb | 173 | 51.95 |
TCO18 Beijing Regionals Round Editorials
TCO18 Beijing Regionals Round was held on 26th May 2018. Thanks to [ltdtl] and [lg5293] for the editorials.
Level Easy JumpingJackDiv1
Jack (the frog), starting at position 0 on day 0, jumps to the east once every day except on every k-th day. When Jack jumps, it moves from position x to position x+dist. You are asked where Jack will be on day n (after Jack jumps on that day, if at all).
Here, we can just simulate according to the problem statement, which would run in O(n) time.
[java]
public class JumpingJackDiv1 {
public int getLocationOfJack(int dist, int k, int n) {
int res = 0;
for (int day = 1; day <= n; day++) {
if (day % k != 0) res += dist;
}
return res;
}
}
[/java]
Bonus: If the limit on n was much larger (say, 10^18), the solution above may time out.
From day 1 to day n (inclusive), Jack would jump (n – floor(n/k)) times because Jack will skip jumping on day k, day 2k, day 3k, …, day floor(n/k)*k. This gives a solution that runs in O(1) time.
[java]
public class JumpingJackDiv1 {
public int getLocationOfJack(int dist, int k, int n) {
return dist * (n – n/k);
}
}
[/java]
Level Medium WordAndPhraseDiv1
We can use dp and process characters from left to right. The main thing we need to remember as we are moving along is whether the last character we processed is a period or not.
Thus, we have dp[i][0] = number of ways to make string of prefix i without the last character being a period, and dp[i][1] = number of ways to make string of prefix i with the last character becoming a period.
As we are processing, if we encounter a underscore character, we can either choose to turn it to a period or not (and we need to check that the beginning of the next word doesn’t begin with a digit).
This solution works in O(n) time.
[java]
public class WordAndPhraseDiv1 {
public int mod = 1000000007;
public int findNumberOfPhrases(String w) {
int n = w.length();
long[][] dp = new long[n+1][2];
dp[0][0] = 1;
dp[0][1] = 0;
for (int i = 0; i < n; i++) { dp[i+1][0] = (dp[i][0] + dp[i][1]) % mod; if (i>0 && w.charAt(i) == ‘_’ && i+1 < n && !Character.isDigit(w.charAt(i+1)))
dp[i+1][1] = dp[i][0];
}
return (int)dp[n][0];
}
}
[/java]
Alternative solution:
Almost identical to the solution above, but one may have noticed that the number of ways to replace underscores by periods are the Fibonacci numbers. For instance, given ‘___’ (3 underscores), there are five ways: {___, .__, _._, __., ._.}. Using this fact, we just need to count the number of contiguous underscores, and multiply the Fibonacci numbers.
One tricky part is, however, to handle corner cases.
(1) When the input string begins with an underscore.
(2) When contiguous underscores are followed by a digit.
For case (1), if the input string begins with an underscore, it cannot be replaced by a period.
For case (2), any underscore followed by a digit cannot be replaced by a period.
Hence, in both cases, we can simply decrease the number of contiguous underscores we counted originally, and still multiply the Fibonacci numbers as explained earlier.
This approach works in O(n) time.
[java]
public class WordAndPhraseDiv1 {
static final long MOD = 1000000007L;
public int findNumberOfPhrases(String w) {
int n = w.length(), i, j, val;
long[] fib = new long[1024];
fib[0] = 1;
fib[1] = 2;
for(i = 2; i < n; i++) fib[i] = (fib[i-1] + fib[i-2])%MOD;
long ans = 1L;
for(i = 1; i < n; i++) { // Ignore the first char of w (w[0]).
if(w.charAt(i) != ‘_’) continue;
for(j=i; j < n && w.charAt(j) == ‘_’; j++); val = (j-i) – ((j==n || (w.charAt(j)>=’0′ && w.charAt(j)<=’9′)) ? 1 : 0);
ans = (ans * fib[val])%MOD;
i=j-1;
}
return (int) ans;
}
}
[/java]
Level Hard MaxNiceMatrixDiv1
Let’s rescale the problem from [a,b] to [0, b-a] for now. For the general input (with range [a,b]), we can simply add the value of a to every term at the end.
If there are k distinct rows, then the sum of each column is at least 0+1+…+(k-1) = k*(k-1)/2
The sum of the whole matrix is at least c * (k * (k-1) / 2)).
On the other hand, we know the sum of each row is exactly b-a, so the sum of the whole matrix is (b-a) * k.
Thus, we have c * k * (k-1) / 2 <= (b-a) * k.
Simplifying gives k <= 2 * (b-a) / c + 1.
We will explicitly construct a matrix to show that k = floor( (2*(b-a) )/c ) + 1 is always possible.
For c = 2 (two columns), this is pretty easy. Use 0, 1, …, k-1 in the first column (from row 0 to row k) and (b-a), (b-a)-1, …, (b-a) – (k-1) in the second column. The sum of each row is exactly (b-a). For instance, when c = 2 and k = 3:
0 (b-a)
1 (b-a)-1
2 (b-a)-2
Every column has distinct numbers, the numbers range between 0 and b-a, inclusive, and each row’s numbers sum up to exactly b-a.
When c is even, this idea can be generalized fairly easily. For the first c-1 columns, simply use the numbers from 0 to k-1 in increasing order for columns 0, 2, 4, …, c-2, and the numbers from k-1 to 0 in decreasing order for columns 1, 3, 5, …, c-3.
For instance, if c = 6 and k = 4, we would have:
0 3 0 3 0 ?
1 2 1 2 1 ?
2 1 2 1 2 ?
3 0 3 0 3 ?
It is easy to see that the sum of the first (c-2) numbers in each row is the same, and because of the second-to-the-last column, the sum of the first (c-1) numbers in each row is an arithmetic sequence. In this example, it is 6, 7, 8, 9. The last column is uniquely determined because each row’s sum must be equal to b-a (recall we ‘scaled’ the numbers from [a, b] to [0, b-a]). You can also easily show that the numbers found this way never exceeds b-a.
When c is odd, things get a bit trickier. We’ll still use the same idea as earlier, but this time we will need to pre-fill the first c-2 columns. For instance, if c = 7 and k = 4, we would have:
0 3 0 3 0 ? ?
1 2 1 2 1 ? ?
2 1 2 1 2 ? ?
3 0 3 0 3 ? ?
Again, the sum of the first c-2 numbers in each row forms an arithmetic sequence (the common difference is +1). The trick is to complement this sequence by another arithmetic sequence (whose common difference is -2). More specifically, starting from k-2 at row 0, we would use k-2, k-4, k-6, …, until this hits 1 or 0 depending on the value of k. Then, at the next row, we start from k-1, using k-1, k-3, and so on.
Using the same example as above (c = 7 and k = 4) we then have:
0 3 0 3 0 2 ?
1 2 1 2 1 0 ?
2 1 2 1 2 3 ? (*)
3 0 3 0 3 1 ?
Notice that now the sums of the first c-1 numbers in four rows are distinct, and therefore the last column (which is uniquely determined from the first c-1 columns) will not have duplicates.
For concreteness, it remains to show that the above solution works for all input values. It’s rather easy to prove this claim when c is even, so let us give a concise version for the case when c is odd.
Each cell must have a value between 0 and b-a, inclusive. Except for the last column, this is trivially true because of the way we choose the numbers. Numbers in the last column never exceed b-a (because we subtract the sum of the other c-1 non-negative numbers from (b-a)). To show that these numbers are non-negative as well, consider row q (where q= floor(k/2)) where the sum of the first c-1 numbers is the largest. In the example above, it’s marke with (*).
This row contains the numbers {q, k-q, q, k-q, …, k-q, q, k-1}. Summing these up yields (k * (c-3)/2 + floor(k/2) + k-1); recall that k = floor(2*(b-a)/c) + 1. With a bit of work, you can show that the sum is no greater than b-a. This bound is sharp; in the above example, for instance, pick b = 11 and a= 0 (which gives us k = floor(2*(b-a)/7) + 1 = 4). Row q (where q = floor(k/2) = 2), we have the sum (2+1+2+1+2+3 = 11) that is equal to b-a.
Lastly, we choose distinct numbers within each column except for the last column; for the last column we simply subtract the sum of the other c-1 values from (b-a). By showing that the sums are distinct, we can prove that the matrix we find is indeed a nice matrix.
Here is a reference solution, using the idea explained above.
This solution runs in linear time (in the size of the output matrix, of course), O((n/c)*c) = O(n) where n = b-a.
[java]
public class MaxNiceMatrixDiv1 {
public int[] getMaxMatrix(int a, int b, int c) {
int n = b-a, m = (n*2)/c + 1, x = m-2, idx = 0;
int[] ret = new int[m*c];
for(int i = 0; i < m; i++) {
int sum = 0;
for(int j = 0; j < c-2; j++) { // alternate [0,m-1] and [m-1,0].
if(j%2 == 0) ret[idx++] = i;
else ret[idx++] = m-1-i;
}
if(c%2 == 0) ret[idx++] = i;
sum = (m-1)*(c/2 – 1) + i;
if(c%2 == 1) { // when c is odd.
ret[idx++] = x;
ret[idx++] = n – sum – x;
x-=2;
if(x < 0) x = m-1;
} else { // when c is even.
ret[idx++] = n – sum;
}
}
for(int i = 0; i < idx; i++) ret[i] = ret[i] + a;
return ret;
}
}
[/java] | https://www.topcoder.com/blog/tco18-beijing-regionals-round-editorials/ | CC-MAIN-2019-09 | refinedweb | 1,768 | 79.09 |
Getting Started With Ruby On Rails
- By Jan Varwig
- March 19th, 2009
- 63 Comments.
I’m taking this approach because Rails is almost 5 years old now and has become very complex. There are a lot of “Create-your-own-blog-in-5-minutes”-type tutorials out there already, and rather than adding another one, I wanted to provide this kind of rough overview to help you decide whether to take this adventure.
You may want to take a look at the following related posts:
The Idea Behind Rails
Ruby on Rails was created by David Heinemeier Hansson as a kind of byproduct of Basecamp’s development at 37signals in 2004. Basecamp was built in Ruby because Hansson found PHP and Java not powerful or flexible enough. It was quite an obscure language back then, without the large eco-system available today. To make development easier, Hansson rolled his own Web development framework, based on simple ideas that had proven successful elsewhere. Rails is founded on pragmatism and established paradigms instead of exotic new ideas. And that’s what made it so successful.. Ruby will only get faster. As the saying goes, you don’t have a performance problem until you have a performance problem, and all this talk should not scare you yet. You haven’t even started. ;)
Now, before I introduce you to the framework, let’s get started with Ruby.
A Gem From Japan
Ruby on Rails owes not only half its name but its entire feel and flexibility to “Ruby,” that neat little language from Japan.
Ruby came out in 1995 and was developed by Yukihiro Matsumoto, or “Matz” as he’s called in the community. Version 1.0 was released in 1999 and slowly gained recognition in the west from then on.
A key point in the spread of Ruby was the release of “Programming Ruby,” also called the “Pickaxe” (a reference to its cover illustration), by the Pragmatic Programmers. “Programming Ruby” was the first comprehensive English guide to the language and API.
Ruby was designed with simple principles in mind. Matz took the most successful and powerful elements from his favorite programming languages — Perl, Smalltak and Lisp — and combined them into one language with easy syntax. One goal was to make Ruby feel “natural, not simple” and to create a language “that was more powerful than Perl, and more object-oriented than Python.” This results in Ruby’s core principle: Everything is an object.
Objects
Let’s stop here and examine this. Really, everything is an object in Ruby.
True and
false are objects, literals are objects, classes are objects. You can call a method on a numeric literal:
>> 5.next => 6
Operators in Ruby are nothing but methods:
>> 5 * 10 => 50 >> 5.*(10) # times-operator called as a method (dot-notation) => 50 # with a parameter (in parentheses)
Ruby is extremely flexible and open. Almost everything about it can be changed or manipulated at runtime:
- You can add and remove methods and variables to and from objects.
- You can add and remove methods and variables to and from classes.
- You can truly manipulate any class this way, even core classes like
Stringand
Integer!
Here’s an example:
>> "hi".repeat(4) NoMethodError: undefined method `repeat' for "hi":String >> class String # Open the string class and add the method >> def repeat(i) >> self * i >> end >> end => nil >> "hi".repeat(4) # Call it again on a fresh String literal => "hihihihi" # And there it is!
Here, I defined the method
repeat on the String core class, and it was immediately available on a string literal.
And he who giveth, taketh away:
>> class String # Open up the method again >> undef_method :repeat # And remove the method >> end => String >> "hi".repeat(4) # Try to call it NoMethodError: undefined method `repeat' for "hi":String
I could have also done this with predefined methods. They are no more “special” than the methods we have defined.
Let’s review the definition of
repeat in the above example for some more interesting tidbits. Note that we’re not saying
return anywhere in the body. That is because in Ruby, methods always implicitly return the value of their last expression. You could of course always jump out of a method by using
return before reaching the last statement, but you don’t have to. The expression we’re returning is
self * i.
Self is equal to
this in Java and
$this in PHP and always refers to the current object. The times-operator on a string repeats the string as often as told by the second operand/parameter,
i in this case.
Loops
You rarely see manual iterations in Ruby, like
for or
while loops. Instead, Collections come with their own iterators that you can pass blocks to, which are executed for every element in the collection:
a = "Hey " [1, 2, 3].each do |num| puts a * num end # Outputs: # Hey # Hey Hey # Hey Hey Hey
What you see here is an array literal containing numbers. On that array, the
each method is called, an iterator that takes a block and calls the block for every element in the array. The block starts with the
do, followed by a list of its parameters enclosed in pipe symbols. Here we have one parameter called
num that will take on the value of the array element in each iteration. Inside the block, we’re simply outputting the result of a * num. The definition of
* on Strings is to repeat the string accordingly. We could have put the String inside the Block, but I wanted to demonstrate that blocks have access to their surrounding scope.
Syntax
Ruby likes to keep the syntax clean and friendly. You can see this in the above examples. Although heavily influenced by Perl, Ruby doesn’t have Perl’s excessive use of special characters. You can use semicolons to end lines, but you don’t have to (and no Ruby programmer does). You don’t need to surround method parameters with braces in unambiguous situations (although it is recommended you do so if they enhance readability), and you especially don’t need to provide empty braces around an empty parameter list. That’s what makes accessors look so much like native properties.
Blocks are framed by
do and
end. You should only use equivalent curly braces if your blocks don’t span several lines. The only significant use of special characters is found at variable declaration. Variables in Ruby are prefixed with special characters to indicate their scope. Variables starting with a lowercase letter are local variables. Variables starting with an uppercase letter are constants. (This means that all classes are constants, too, since classes start with uppercase letters.) Instance variables start with an
@. Class variables that are shared among all instances of a class start with
@@. Finally, global variables all start with a
$.
You’ll often find methods ending in
? or
!. These are not special characters. It is merely conventional in Ruby to use question marks for methods that query an object for a Boolean condition, like
Array#empty?, or exclamation marks for methods that are destructible:
>> a = [5, 1, 9, 2, 7] # Create an array and store it in a => [5, 1, 9, 2, 7] >> a.sort # sort merely returns a new, sorted array => [1, 2, 5, 7, 9] >> a => [5, 1, 9, 2, 7] # a still is in its original order >> a.sort! # sort! instead sorts the original array => [1, 2, 5, 7, 9] >> a => [1, 2, 5, 7, 9] # a was changed
Conditionals
Conditionals in Ruby are very similar to other programming languages, with two notable exceptions. First, it’s possible to put a conditional after the statement it protects to make the code more readable:
execute_dangerous_operation() if user.is_authorized? # is equal to if user.is_authorized? execute_dangerous_operation() end
Secondly, Ruby has not only an
if but an
unless. This is a syntactic nicety for when you want to check for the absence of a condition in a more readable manner:
unless user.is_admin? user.delete else raise "Can't delete admins" end
Symbols
Sometimes you’ll see names starting with a
: (colon). These are a very special feature of Ruby called symbols. Symbols can be used to index hashes or mark states in a variable like you would with an ENUM in C. They are very similar to Strings but also very different. The point about symbols is that they don’t really occupy space in memory, and the same symbol literal always resolves to the exact same symbol:
>> "a".object_id # object_id returns Ruby's internal identifier for an object => 3477510 >> "a".object_id => 3475550 # a new object on the heap >> :a.object_id => 184178 >> :a.object_id => 184178 # the same literal refers to the exact same Symbol object
You’ll find them very often as parameters to methods, where they indicate how a method should work,
User.find(:all) #find all users User.find(:first) #find the first user
or as pointers to methods and variables (see the
undef_method example in the “Objects” paragraph above).
Classes and Modules
Ruby supports single inheritance only, but for added flexibility it supports a feature called Mixins. In Ruby, it’s possible to define Modules that contain Methods and constants and to include these modules in a class via the
include method. This way, you can extend the functionality of a class very easily.
Many of Ruby’s core classes even use this mechanism.
Array and
Hash, for example, both include the
Enumerable module to provide a lot of convenience methods for iterating over their contents.
Often, Modules pose certain requirements to classes that include them. The
Enumerable Module, for example, requires classes to provide at least an
each method and an implementation of
<=>, too, if its sorting features are to be used.
Modules also serve other purposes. Most importantly, they can be used to organize code into namespaces. Because classes are constants (which means you can’t assign another class to the same name), they can be stored in modules. These modules can then be nested to form namespaces.
These paragraphs probably won’t enable you to write Ruby programs, but you should be able to understand the code samples in this article now. If you want to explore Ruby a little, try the great interactive tutorial at Try Ruby2, or take a peek at one of the books listed at the end of this article. If you just want to see some more code samples, check out the Wikipedia page on Ruby3.
In the second part of this tutorial we will get rolling with Ruby on Rails, install the engine, take a closer look at Rails’ inner workings and discover main advantages of Ruby on Rails. Please stay tuned.
(al)
Footnotes
- 1
- 2
- 3(programming_language
↑ Back to top Tweet itShare on Facebook | http://www.smashingmagazine.com/2009/03/getting-started-with-ruby-on-rails/ | CC-MAIN-2015-32 | refinedweb | 1,798 | 63.7 |
au3scr 0 Posted January 18, 2009 (edited) Hi , I am trying to make function that returns dir size 1-st msgbox (in func) shows right data,but second msgbox (in source it is beforefunc) shows me wrong info, it always shows 0 (zero) how I can make that secont msg box show right information? $sourcedir = "C:\windows" $ProgramSize = 0 _getsize($sourcedir,$ProgramSize) MsgBox(1,1,$ProgramSize) Func _getsize ($sourcedir,$ProgramSize) $ProgramSize = Round((DirGetSize($sourcedir) / 1024 )/1024,0) MsgBox(1,1,$ProgramSize) Return $ProgramSize EndFunc and How I could use it in If sentences later? i wanna do something like: IF _getsize() < 30 then _extraFunc endif I have never made any if sentences with funcs. Edited January 18, 2009 by au3scr Share this post Link to post Share on other sites | https://www.autoitscript.com/forum/topic/87920-need-functions-help-same-problem-but-different-func/ | CC-MAIN-2018-47 | refinedweb | 130 | 50.7 |
#include <ctime>
#include <iostream>
#include <cstdlib>
using namespace std;
int main()
{
int num = 0;
int num2 = 0;
int user = 0;
int answer1 = 0;
int count = 0;
srand(unsigned(time(0)));
for(int i=1 ; i<=5 ; i++)
{
num = (rand()%8)+ 2;
num2= (rand()%8)+ 2;
answer1=num*num2;
cout<<"\nWhat is "<<num<<" x "<<num2<<endl;
cin>>user;
if(answer1==user)
cout<<"Correct!\n";
count++;
if(answer1!=user)
cout<<"Wrong! -> "<<num<<" x "<<num2<<" = "<<answer1;
}
cout<<"\nYou got "<<count<<" out "<<"5 right!\n";
system("pause");
return 0;
}
//I have this started for the below assignment. Can anyone please provide insight as to why I cant build on this solution.
Write a program that keeps generating two random numbers between 1 and 10 and asks the user for the product of the two numbers, e.g.: "What is 4 x 6?". If the user answers correctly, the program responds with "Right!"; otherwise, it displays: Wrong! 4 x 6 = 24.
Begin by asking the user how many questions to ask. Generate as many pairs of numbers as specified and get the answers from the user for each. If at any time, both numbers are the same as last time, generate two new numbers before asking for the answer. Continue generating 2 new numbers until at least one is different from last time.
After presenting the number of pairs of numbers specified and getting the answers, display how many the user got right; e.g.: You got 4 of 5 right. Then, ask if he or she wants to play again, like so: "Do you want to play again? [y/n]". If the user answers with 'y' or 'Y', it again reads the number of questions to ask and generates that many pairs of numbers and reads the answers like before. If the answer is n or N, it quits generating numbers. If the answer is anything but y, Y, n or N, it tells the user to enter one of those letters until it is.
When the user decides to quit and has got less than 75% of all the questions right, the program displays the multiplication table (1x1 through 10x10) before terminating.
After displaying the table, randomly generate two numbers between 1 and 10, display their product and first number and ask the user to guess the second as more practice. For example, the program will generate 7 and 9 and will display 63 and 7 and the user must guess the second number (i.e.: 9). Do this 3 times. Do not repeat code. Use a loop to do this 3 times.
Use a nested for loop to display the table; a bunch of cout statements will not be acceptable. You must also use a loop for any part that calls for repetition such as generating 5 pairs of numbers.
The following is a sample interaction between the user and the program:
Enter the number of questions to ask: 5
1. What is 3 x 9? 27
Right!
2. What is 2 x 7? 14
Right!
3. What is 8 x 9? 63
Wrong! 8 x 9 = 72
4. What is 6 x 3? 21
Wrong! 6 x 3 = 18
5. What is 2 x 9? 18
Right!
You got 3 out of 5 right which is 60%.
Play agian? [y/n] n
Forum Rules | http://forums.codeguru.com/showthread.php?536775-C-assistance-for-my-beginner-class&p=2116281&mode=threaded | CC-MAIN-2015-32 | refinedweb | 553 | 82.85 |
Bench Signbit Check vs Float Check
Last updated on
Floats have a bit dedicated to if the value is a negative or not, I was wondering how much performance difference was checking the bit vs a function that compares against zero.
#include <stdint.h> #include <stdio.h> #include <stdlib.h> #if 0 int sign(float a) { return a >= 0.f ? 1 : 0; } #else int sign(float a) { return !((*(uint32_t*)&a >> 31) & 0xFF); } #endif #define COUNT (1 << 13) int main() { volatile int seed = 123; srand(seed); float data[COUNT] = {0}; int i; for(i = 0; i < COUNT; ++i) { data[i] = ((float)(rand() % 1000) - 500.f) / 10000.f; } int result = 0; uint64_t start = __builtin_ia32_rdtsc(); for(i = 0; i < COUNT; ++i) { result += sign(data[i]); } uint64_t end = __builtin_ia32_rdtsc(); printf("Result: %d Time: %d\n", result, (int)(end - start)); return 0; }
build and go
cc signbit.c -O2 && ./a.out
Results
Signbit seems to win out in all cases, but this is small enough where we can really say there is no difference. Unless you have a use case which has you doing millions of these its really not going to be worth it. | https://blog.cooperking.net/posts/2019-06-10-bench_float_signbit_vs_check/ | CC-MAIN-2021-39 | refinedweb | 190 | 69.41 |
The Simple Way to Parse JSON Responses Using Groovy and Katalon Studio
Many people have asked how to retrieve information from JSON responses and parse the JSON format in Katalon Studio. Check out this post to learn more!
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Many people in the Katalon forum have asked about retrieving information from JSON responses and parsing the JSON format in the Katalon Studio. In this post, I will show a simple way on how to do so. Let's get started.
JSON Response Example
Suppose we have the following JSON response, and we want to parse and retrieve its data:
{"menu": { "id": "file", "tools": { "actions": [ {"id": "new", "title": "New file"}, {"id": "open", "title": "Open File"}, {"id": "close", "title": "Close File"} ], "errors": [] }}}
JsonSlurper
We use this Groovy helper class to parse JSON strings. We need to create a new instance of
JsonSlurper and call the
JsonSlurper.parseText method. Here is the sample code:
import groovy.json.JsonSlurper String jsonString = '''{"menu": { "id": "file", "tools": { "actions": [ {"id": "new", "title": "New File"}, {"id": "open", "title": "Open File"}, {"id": "close", "title": "Close File"} ], "errors": [] }}}''' JsonSlurper slurper = new JsonSlurper() Map parsedJson = slurper.parseText(jsonString)
The parsed JSON response is now stored in a variable called
parsedJson. In our case, it is the
Map data structure, but sometimes it may be something else.
JsonSlurper also provides a couple of
JsonSlurper overloading methods, which can be used if your JSON input is
File ,
Reader ,
InputStream , or a URL other than String. For further information, please refer to the JsonSlurper documentation.
Get a Key Value
Let's say you want to get a value of id from the JSON response above. JSON is a structured document, so you can get any element using its absolute path. Check out this example:
String idValue = parsedJson.menu.id String idValue2 = parsedJson.get("menu").get("id")
As you can see, there are two ways to get it. One is to access
Map objects using the dot notation (.). The other is to use
get methods from
Map ,
List , and
Set as you do in Java.
Basically, the
parsedJson variable is a type of
Then. To get the inner
Map, you call
parsedJson.
menu is the String key. This method returns the inner
Map on which you can call other get methods until you reach your key.
Verify if a Key Is Present in JSON
If you want to verify if a selected key is present in a JSON response, you can use the similar code as below:
import com.kms.katalon.core.util.KeywordUtil String getSelectedKey = parsedJson.menu.id if(getSelectedKey == null) { KeywordUtil.markFailed("Key is not present") }
It is a simple check for the null — if the given key is not found, null is returned. But, there is one special case when this code won’t work, that is, if key “id” has value null in your JSON. For such cases, you should use more robust code:
boolean isKeyPresent = parsedJson.get("menu").keySet().contains("id") if (!isKeyPresent) { KeywordUtil.markFailed("Key is not present") }
You get all keys from the "menu" object and then check if it contains the key you are looking for.
Get an Array Element
Your JSON response may also contain arrays. Like any array in Java or Groovy, you can access an array element using
arrayName[index].
For example, we can get the "title" value of the first object in the "actions" array as below
String idValue = parsedJson.menu.tools.actions[0].title String idValue2 = parsedJson.get("menu").get("tools").get("actions").get(0).get("title")
In this example, we access the item with the index of 0, the first item in the array (the index is zero-based).
Get an Array Element Based on Some Condition
A more usual case is when you want to get the exact array element based on some specific condition. For example, you get the "title" value of an object whose "id" is "Open." You can do using the following:
def array1 = parsedJson.menu.tools.actions String onlickValue1 = "" for(def member : array1) { if(member.id == 'Open') { onlickValue1 = member.title break } }
I used the for-each loop in this case. This loop checks every item in the array until the condition is met. If so,
onlickValue1 is assigned to the item's title.
JSON Data Types
The JSON format supports a few data types, such as
String,
number,
Boolean, and
null . If you are not sure what the data type is, you can just use the keyword
def.
def myVar = ‘get value from json here’.
A rule of thumb is that a
String value is enclosed in quotes, numbers unquoted (floating point may be present as well), and Boolean. But, initializing a variable using
def is always a good choice when you are not sure about its type.
Conclusion
This tutorial offers a few basic best practices for working with JSON strings in Katalon Studio. JSON is the most common format returned from API/Web Services. When you perform API testing, you likely have to deal with JSON responses. Hopefully, these practices are useful for your API testing!
Published at DZone with permission of Marek Melocik. See the original article here.
Opinions expressed by DZone contributors are their own. | https://dzone.com/articles/the-simple-way-to-parse-json-responses-using-groov | CC-MAIN-2021-43 | refinedweb | 875 | 65.42 |
NB-IoT in Austria
Hello,
i am trying to connect to NB-IoT in Austria. The APN data is from my provider A1. I would like to send some sensor data over NB-IoT to test it.
when i try to attach it fails everytime.
Do you have any advice for me how can I attach the modem and how could I send/receive data? I didn't find many documentation about that..
Thank you.
My Code:
import pycom import socket import time from network import LTE from SI7006A20 import SI7006A20 # Disable WiFi from network import WLAN wlan = WLAN() wlan.init() # Disable Heartbeat pycom.heartbeat(False) pycom.rgbled(0x0) lte = LTE() lte.send_at_cmd('AT+CFUN=0') # disable modem lte.send_at_cmd('AT!="clearscanconfig"') # clear scanned frequencies lte.send_at_cmd('AT!="addscanfreq band=20 dl-earfcn=6300"') # set scanned frequency lte.send_at_cmd('AT+CGDCONT=1,"IP","try.a1.net"') # set APN (Access Point Name) lte.send_at_cmd('AT+COPS=?') # scan available networks lte.send_at_cmd('AT+CFUN=1') # enable modem while not lte.isattached(): print("attaching...") pass lte.connect() while not lte.isconnected(): print("connecting...") pass # now use socket as usual...```
@dommei That's means: "not registered, MT is not currently searching an operator to register to". At my device, it toggles between 2,0 and 2,2. The response you need is 2,1 or 2,5.
The AT command set document is here:
@robert-hh
hey again, now i have
2,0 as return value
any advice now? thank you
If a lack of band 8 support, this is the same problem that I have with Vodafone Australia!
I am waiting for a response to my RMA request.
Peter.
@dommei 2,4 means:
2: scanning with unsolicited messages enabled
4: unknown (e.g. out of E-UTRAN coverage)
So: not attached
@robert-hh The return value of AT+CEREG? is 2.4
@dommei What is the result of:
lte.send_at_cmd('AT+CEREG?')
You may have to wait for a while, until the device attaches, and obviously you need a specific SIM for NB-IoT.
Edit: Looking at the press announcement, it is likely that they use Band 8 (900 MHz band). This is not supported by the Pycom devices yet. You have to send them back to Pycom for an fix. See this post:
yes Austria not Australia...
The APN data is from the provider and they said they activated NB-IoT in my area. The bad thing is that they didn't test it with pycom devices.. so thats the reason why i ask here for help :)
@tuftec said in NB-IoT in Austria:
@robert-hh ha ha!!!
My bad.
Cheers.
There are quite a few jokes about that.
@robert-hh ha ha!!!
My bad.
Cheers.
Hi Dom,
Firstly, you need Band 8 support for Vodafone Australia. This is currently not supported in the existing FiPy firmware. There is an upgrade coming, but you might need to srnd your FiPy back to Pycom. See annocements elsewhere in the forum.
Secondly, you need to contact Vadafone to obtain correct SIMs and access details.
Good luck.
Cheers.
Peter. | https://forum.pycom.io/topic/3846/nb-iot-in-austria | CC-MAIN-2019-09 | refinedweb | 514 | 77.23 |
SCS web serviceAnitallica Apr 14, 2017 1:53 AM
Hi everyone,
I have seen, in a software that can manage AMT machines, a reference to a "SCS Web service" URL that could be used to retrieve a list of AMT devices that the SCS is aware of.. does anyone know if this feature (still) exists, and if yes, how it can be configured? I didn't find anything resembling this in the Intel documentation, or in my SCS installation.
All I found from the Intel documentation was a reference to an AMTConfServer.exe, which I don't have.. I installed the SCS 11.1 from a SCS_download_package_11.1.0.75 downloaded from Intel, installed it from the RCS folder, and under Program Files I have a folder Intel containing Console, License, and Service. No AMTConfServer. What am I missing?
Thanks in advance!
1. Re: SCS web servicemichael_a_intel Apr 17, 2017 11:55 AM (in response to Anitallica)
Hello Anitallica,
A few years ago, we had a utility called AMTConfServer.exe, however, it was replaced with RCSServer.exe. To retrieve a list of AMT devices that SCS is aware of, SCS needs to be installed in database mode and you're running as a user that has rights to the Intel_RCS_Systems namespace, you can query WMI for this information directly using Powershell:
Get-WmiObject -computername = "RCSFQDN" -Namespace Root\Intel_RCS_Systems -Class RCS_AMT | where {$_.AMTFqdn -like "*.DOMAINSUFFIX"} | Format-Table AMTFqdn, AMTVersion
(Alternatively, easier to see) Get-WmiObject -computername = "RCSFQDN" -Namespace Root\Intel_RCS_Systems -Class RCS_AMT | where {$_.AMTFqdn -like "*.DOMAINSUFFIX"} | Format-Table AMTFqdn, AMTVersion
Please let us know if this helps.
2. Re: SCS web serviceAnitallica Apr 18, 2017 10:59 AM (in response to michael_a_intel)
Thanks Michael,
I was hoping there would still be a way similar to the old AMTConfServer.exe web interface, since we already have an implementation for that.. is there any documentation on how that old web interface looked like, and what it displayed?
For the new RCSServer.exe, is there any other way to get the machine list, other than querying WMI?
Thanks.
3. Re: SCS web servicemichael_a_intel Apr 20, 2017 11:54 AM (in response to Anitallica)
Hello Anitallica,
My apologies for the delayed response, it's not without reason. I've reached out internally for anything related to AMTConfServer.exe and i have had no luck. And I am not aware of an alternative method of querying WMI.
Regards,
Michael
4. Re: SCS web serviceAnitallica Apr 21, 2017 2:59 AM (in response to michael_a_intel)
No worries Michael, thank you very much for your effort!
Best regards,
Anita | https://communities.intel.com/thread/113329 | CC-MAIN-2018-43 | refinedweb | 433 | 56.25 |
Jul 26, 2006 02:00 PM|tusharb|LINK
I am upgrading a VS 2003 ASP.NET project to VS 2005.
I have converted it to a Web Site Project and also to an Web Application Project.
I have used the old System.Web.Mail namespace in the project and ConfigurationSettings.AppSettings[] at several places.
I get several compilers warnings (coz these are old/deprecated API's) on the Web Application project but none whatsoever on the Web Site project.
Don't know why ?? Any ideas.
Thanks a lot for ur help
0 replies
Last post Jul 26, 2006 02:00 PM by tusharb | https://forums.asp.net/t/1011826.aspx?Missing+Compiler+warning+on+Web+site+project | CC-MAIN-2017-34 | refinedweb | 103 | 78.04 |
You'll find an example showing how to use the File and Directory classes on the CD-ROM. This example is called copier, and it lets you create a directory and then copy a file to that new directory. As discussed in the In Depth section of this chapter, to use the File and Directory classes, I first import the System.IO namespace, then use the Directory class's CreateDirectory method to create a new directory, using the path the user has entered into a text box. Then I use an Open File dialog box to determine what file the user wants to copy, and use the File class's Copy method to actually copy the file:
Imports System.IO Public Class Form1 Inherits System.Windows.Forms.Form 'Windows Form Designer generated code Private Sub Button1_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button1.Click Try Directory.CreateDirectory(TextBox1.Text) Catch MsgBox("Could not create directory.") Exit Sub End Try MsgBox("Directory created.") End Sub Private Sub Button2_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button2.Click Try If OpenFileDialog1.ShowDialog <> DialogResult.Cancel Then File.Copy(OpenFileDialog1.FileName, TextBox1.Text & "\" & _ OpenFileDialog1.FileName.Substring(_ OpenFileDialog1.FileName.LastIndexOf("\"))) End If Catch MsgBox("Could not copy file.") Exit Sub End Try MsgBox("File copied.") End Sub End Class
And that's all it takes—I didn't need to open the file, or even create objects of the File and Directory classes. You can see the results of this code after the files has been copied to the new directory in Figure 13.4. | http://www.yaldex.com/vb-net-tutorial-2/library.books24x7.com/book/id_5526/viewer.asp@bookid=5526&chunkid=0795030825.htm | CC-MAIN-2018-26 | refinedweb | 273 | 52.26 |
I'm getting errors on lines 8 & 43. I can't figure out what I'm doing wrong here (besides beating my head against the desk.)
#include <iostream> using namespace std; { try { if (num1 < 0) throw low; if (num2 < 0) throw low; if (num3 < 0) throw low; if (num4 < 0) throw low; if (num1 > 100) throw high; if (num2 > 100) throw high; if (num3 > 100) throw high; if (num4 > 100) throw high; catch (...) { cout << "Number out of range." << endl; } } int main() { int num1, num2, num3, num4; int avg; cout << "Enter four numbers to be averaged." << endl; cout << "\nNumbers must be between 0 and 100." << endl; avg = (num1 + num2 + num3 + num4)/4; cout << "The average is: " << avg << endl; } return 0; } | https://www.daniweb.com/programming/software-development/threads/36777/exception-handling | CC-MAIN-2017-34 | refinedweb | 119 | 88.67 |
import "upspin.io/dir/server/tree"
Package tree implements a tree whose nodes are DirEntry entries.
blocks.go tree.go watch.go
Tree is a representation of a directory tree for a single Upspin user. The tree reads and writes from/to its backing Store server, which is configured when instantiating the Tree. It uses a Log to log changes not yet committed to the Store.
New creates an empty Tree using the server's config and the set of logs for a user. Config is used for contacting StoreServer, defining the default packing and setting the server name. All fields of the config must be defined. If there are unprocessed log entries in the Log, the Tree's state is recovered from it. TODO: Maybe New is doing too much work. Figure out how to break in two without returning an inconsistent new tree if log is unprocessed.
Close flushes all dirty blocks to Store and releases all resources used by the tree. Further uses of the tree will have unpredictable results.
Delete deletes the entry associated with the path. If the path identifies a link, Delete will delete the link itself, not its target.
If the returned error is upspin.ErrFollowLink, the caller should retry the operation as outlined in the description for upspin.ErrFollowLink. (And in that case, the DirEntry will never represent the full path name of the argument.) Otherwise, the returned DirEntry will be nil whether the operation succeeded or not.
Flush flushes all dirty dir entries to the Tree's Store.
List lists the contents of a prefix. If prefix names a directory, all entries of the directory are returned. If prefix names a file, that file's entry is returned. List does not interpret wildcards. Dirty reports whether any DirEntry returned is dirty (and thus may contain outdated references).
If the returned error is upspin.ErrFollowLink, the caller should retry the operation as outlined in the description for upspin.ErrFollowLink. (And in that case, only one DirEntry will be returned, that of the link itself.)
Lookup returns an entry that represents the path. The returned DirEntry may or may not have valid references inside. If dirty is true, the references are not up-to-date. Calling Flush in a critical section prior to Lookup will ensure the entry is not dirty.
If the returned error is ErrFollowLink, the caller should retry the operation as outlined in the description for upspin.ErrFollowLink. Otherwise in the case of error the returned DirEntry will be nil.
OnEviction implements cache.EvictionNotifier.
Put puts an entry at path p into the Tree. If the entry exists, it will be overwritten.
If the returned error is ErrFollowLink, the caller should retry the operation as outlined in the description for upspin.ErrFollowLink (with the added step of updating the Name field of the argument DirEntry). Otherwise, the returned DirEntry will be the one put.
PutDir puts a DirEntry representing an existing directory (with existing DirBlocks) into the tree at the point represented by dstDir. The last element of dstDir must not yet exist. dstDir must not cross a link nor be the root directory. It returns the newly put entry.
String implements fmt.Stringer.
func (t *Tree) Watch(p path.Parsed, sequence int64, done <-chan struct{}) (<-chan *upspin.Event, error)
Watch implements upspin.DirServer.Watch.
Package tree imports 15 packages (graph) and is imported by 1 packages. Updated 2019-05-18. Refresh now. Tools for package owners. | https://godoc.org/upspin.io/dir/server/tree | CC-MAIN-2019-47 | refinedweb | 577 | 68.57 |
Not sure why, finally just sent it through queues, but would like this to work.
Here is the source code for what does not work. I have patched a since wave to the I2S and can see that it works. I have also done notefrequency on the USB input and know that it works, and since I have used queues and that works it is just the AudioConnection.
#include <Audio.h>
#include <Wire.h>
#include <SPI.h>
#include <SD.h>
#include <SerialFlash.h>
// GUItool: begin automatically generated code
AudioInputUSB usb1; //xy=226,133
AudioOutputI2S i2s1; //xy=399,126
AudioConnection patchCord1(usb1, 0, i2s1, 0);
AudioConnection patchCord2(usb1, 1, i2s1, 1);
// GUItool: end automatically generated code
void setup() {
// put your setup code here, to run once:
AudioMemory(60);
}
void loop() {
// put your main code here, to run repeatedly:
} | https://forum.pjrc.com/threads/62561-USB-input-to-I2S-output-does-not-work-for-Teensy4-1?s=164c9147f72a828120bfaf56f688477e | CC-MAIN-2020-45 | refinedweb | 137 | 65.83 |
We organize known future work in GitHub projects. See Tracking SPIRV-Tools work with GitHub projects for more.
To report a new bug or request a new feature, please file a GitHub issue. Please ensure the bug has not already been reported by searching issues and projects. If the bug has not already been reported open a new one here.
When opening a new issue for a bug, make sure you provide the following:
For feature requests, we use issues as well. Please create a new issue, as with bugs. In the issue provide
Before we can use your code, you must sign the Khronos Open Source.
See README.md for instruction on how to get, build, and test the source. Once you have made your changes:
clang-format -style=file -i [modified-files]can help.
Fixes you do this, the issue will be closed automatically when the commit goes into master. Also, this helps us update the CHANGES file.
The reviewer can either approve your PR or request changes. If changes are requested:
After the PR has been reviewed it is the job of the reviewer to merge the PR. Instructions for this are given below.
The formal code reviews are done on GitHub. Reviewers are to look for all of the usual things:
When looking for functional problems, there are some common problems reviewers should pay particular attention to:
We intend to maintain a linear history on the GitHub master branch, and the build and its tests should pass at each commit in that history. A linear always-working history is easier to understand and to bisect in case we want to find which commit introduced a bug.
The following steps should be done exactly once (when you are about to merge a PR for the first time):
It is assumed that upstream points to git@github.com:KhronosGroup/SPIRV-Tools.git or.
Find out the local name for the main github repo in your git configuration. For example, in this configuration, it is labeled
upstream.
git remote -v [ ... ] upstream (fetch) upstream (push)
Make sure that the
upstream remote is set to fetch from the
refs/pull namespace:
git config --get-all remote.upstream.fetch +refs/heads/*:refs/remotes/upstream/* +refs/pull/*/head:refs/remotes/upstream/pr/*
If the line
+refs/pull/*/head:refs/remotes/upstream/pr/* is not present in your configuration, you can add it with the command:
git config --local --add remote.upstream.fetch '+refs/pull/*/head:refs/remotes/upstream/pr/*'
The following steps should be done for every PR that you intend to merge:
Make sure your local copy of the master branch is up to date:
git checkout master git pull
Fetch all pull requests refs:
git fetch upstream
git checkout pr/1048
Rebase the PR on top of the master branch. If there are conflicts, send it back to the author and ask them to rebase. During the interactive rebase be sure to squash all of the commits down to a single commit.
git rebase -i master
Build and test the PR.
If all of the tests pass, push the commit
git push upstream HEAD:master
Close the PR and add a comment saying it was push using the commit that you just pushed. See as an example. | https://skia.googlesource.com/external/github.com/KhronosGroup/SPIRV-Tools/+/1cea3b7853c8914ed9c6428687562ad44ced5d5a/CONTRIBUTING.md | CC-MAIN-2019-51 | refinedweb | 546 | 62.88 |
On 02/25/2013 09:08 PM, Gao Yongwei wrote: > > I thinks it's better that if we can put dnsmasq args or options in a > conf file, so we can do some custom through this conf file. > I've added a Bug 913446 in redhat bugzilla,but seems no one take care > of this bug? This has been discussed extensively on the list before, and we specifically *don't* want to do it. Gene Czarcinski even submitted a patch that would do it, and that patch was rejected (and I *think* he agreed with our reasoning :-) The problem is that when you allow a user to silently subvert the config that is shown in libvirt's XML, and the system stops working, the user will send a plea for help to irc/mailing list (or open a ticket with their Linux support vendor), and the people they ask for support will say "show us the output of 'virsh net-dumpxml mynetwork'", which they will send, and then a comedy of errors will ensue until someone finally realizes that there is some "extra" configuration that the user isn't telling us about. There are two solutions to that: 1) add an element for the specific option you want to control in libvirt's network XML. Some knobs are already there, and others are being added. 2) add a private "dnsmasq" namespace to libvirt's network xml, with provisions for directly passing through dnsmasq commandline options from the xml to the conf file. This would be similar to what has already been done for qemu: The difference between these and the idea of simply allowing a user-written conf file is that everything about the network's config would then be available in "virsh net-dumpxml $netname". As far as the bug you've filed, it takes awhile for bugs to be triaged. (At a first glance, it seems reasonable to add such an option, since it is a standard part of the dhcp protocol. We might need to do something about specifying different units for the lease time.) | https://www.redhat.com/archives/libvir-list/2013-February/msg01608.html | CC-MAIN-2014-23 | refinedweb | 348 | 57.84 |
On Ubuntu 10.04 by default Python 2.6 is installed, then I have installed Python 2.7. How can I use
pip install
pip install beautifulsoup4
import bs4
No module named bs4
Use a version of
pip installed against the Python instance you want to install new packages to.
In many distributions, there may be separate
python2.6-pip and
python2.7-pip packages, invoked with binary names such as
pip-2.6 and
pip-2.7. If pip is not packaged in your distribution for the desired target, you might look for a setuptools or easyinstall package, or use virtualenv (which will always include pip in a generated environment).
pip's website includes installation instructions, if you can't find anything within your distribution. | https://codedump.io/share/d4E49ATDzks3/1/how-to-install-a-module-use-pip-for-specific-version-of | CC-MAIN-2017-34 | refinedweb | 126 | 68.47 |
Don't see any "onclick" events inside the p:lightBox
So I guess you could use the help of jQuery... The following should work just fine (add to your js file or script tag)
jQuery(document).delegate(".imagebox", "click", function (event) { light.hide(); });
jQuery(document).delegate(".ui-lightbox-content-wrapper", "click", function (event) { light.hide(); });
....delegate("#idOfLightBox ",....
<p:lightBox ...
You are welcome , I looked at the first primefaces showcase example that's why took that class as an anchor... (The Important part is the Idea behind...)
jsf 2 - Primefaces Lightbox: How to call hide()-method - Stack Overflo...
Since PrimeFaces 3.3, you'd need to explicitly set the lazy attribute of the repeating component to true in order to enable the support for LazyDataModel.
<p:dataTable ...
Arrrrgggghh...So thats the reason, I have built a small app that uses lazydatamodel using Primefaces 3.1. I was just following along when I encounter this in the latest 3.4 build.. Thanks as always BalusC..
You're welcome. Been there, done that ;)
I have version 3.5 and i already set lazy="true" in my dataTable. But still load() method in lazyDataModel is not getting called. Do you have any idea ?
Even with Datatable attribute lazy="true", some other Datatable attributes can inhibit lazy loading, causing UnsupportedOperationException with message "Lazy is loading not implemented", (generated by the load() stub in LazyDataModel). Try removing attributes such as sortMode and sortBy, and set paginator="true" rather than having it set by a bean property.
jsf 2 - PrimeFaces lazydatamodel load method not called - Stack Overfl...
Today I hit this exact same problem with PrimeFaces 5.1. In my case I had no nested forms and I was already setting the process attribute on the p:commandButton with the form elements I wanted to be processed. However this didn't work yet.
The "solution" was to add @this to the list of components to process, like this:
<p:commandButton
Without @this (which is not usually needed, since the button itself shouldn't need to be processed/validated) I found no way to make any of these to work inside a composite:
<p:commandButton action="#{bean.myAction}"...>
<p:ajax event="click" action="#{bean.myAction}"...>
<p:remoteCommand
By debugging the application, I saw that the validation and update model phases were correctly executed, but then in the invoke application phase no queued event was present and hence no action was performed. Actually, I could specify anything I liked inside the action and actionListener attribute values of <p:commandButton> without having either PrimeFaces or JSF complain in any way.
These, instead, do work as they should, but you don't have partial processing in place, so they may not be a viable solution:
<p:commandButton action="#{bean.myAction}" ajax="false"...>
<p:commandButton type="button"...>
<f:ajax event="click" action="#{bean.myAction}"...>
It must be a PrimeFaces bug.
button is not fired, if it is not processed. it makes sense.
It does not, since the "process" attribute indicates which other fields should be processed/submitted. Setting "@this" in the process attribute is not required for buttons outside a composite. And, if it were, it would be at least "redundant".
jsf 2 - PrimeFaces CommandButton Action not called inside Composite - ...
You seem to be expecting that the valueChangeListener method in the server side is called immediately when a change event occurs on the client side. This is not correct. It will only be invoked when the form is submitted to the server and the new value does not equals() the old value.
Add onchange="submit()" so that JavaScript will submit the form whenever you change the value:
This is however very JSF-1.x-ish and poor for user experience. It will also submit (and convert/validate!) all other input fields which may not be what you want.
Make use of an ajax listener instead, for sure if you are not interested in the actual value change (i.e. the old value is not interesting for you), but you're actually interested in the change event itself. You can do this using <f:ajax> or in PrimeFaces components using <p:ajax>:
<p:selectOneMenu <p:ajax <f:selectItems </p:selectOneMenu>
ValueChangeEvent
AjaxBehaviorEvent
Thanks. I was exxpecting the PrimeFaces component to do the submit() as part of the component's ajax behavior.
Your selcond solution worked very well for be, but only if i changed the <f:ajax to <p:ajax... also I think it's good to point out what the signature or the callback method should be. so in this case it would be public void accountValueChange(ValueChangeEvent event){...}
BalusC is spot on.Even more fun, although I am not sure if it is legit., is just to insert <p:ajax></p:ajax> inside the menu and leave the valueChangeListener attribute of the menu intact. For some reason the ajax will fire the valueChangeEvent when the item changes. I have tested this exhaustively to make an immediate change to a locale and it works a dream.
@Tim: The value change listener is fired when the submitted value differs from the initial value. All what ajax does is submitting the form. That's not so weird as you seem to imply. However, if you're not intersted in the change itself, but only in the newly submitted value, then a value change listener is the wrong tool for the job. See also stackoverflow.com/questions/11879138/
jsf 2 - How do I get PrimeFaces
to call valueChangeL...
When you used the composite component, was it already placed in a h:form tag? When you have nested forms, command button action isn't triggered.
Another issue can be the ajax parts that you are trying. Primefaces button has the update attribute, but the standard JSF one does not have that. It will do always a complete refresh of the page (except when nested in or f:ajax tag is used inside it)
jsf 2 - PrimeFaces CommandButton Action not called inside Composite - ......
You can't and shouldn't nest forms.
ClientMaster.xhtml
<ui:include </h:form>
</h:form> <ui:include
jsf 2 - primefaces commandbutton actionlistener not called - Stack Ove...
Your listener is not being called, as you probably have some validation errors. In the JSF Life-cycle Phase 3 is the "Process Validations" Phase, if this phase fails JSF will immediately jump to phase 6, which is "Render Response" Phase. So phase 5 "Invoke application" where the listener gets called, will be skipped.
Make sure that neither deviceBean nor inputControlGroupId is null and applies the given constraint.
#{deviceBean.inputControlGroupId}
Thanks Sonic, that seems to be on the right track. However neither deviceBean nor inputControlGroupId are null but the param doesn't always exist. The cgId viewparam is an optional input param so when it is not defined I am getting the issue but when it is defined I don't. Also why don't I get some validation exception? I can remove the validation tag as it is not too important in my case but would be nice to fully understand what is going on.
As cgId is an optional param you should render the validation tag only if this param has been set. You can do this by adding a corresponding <c:if/> test. As the variable has not been set, you will get a RuntimeException Nullpointer Exception, not a checked Validation Exception, when JSF tries to access this parameter in it`s validation phase. This is why your program crashes.
jsf 2 - PrimeFaces Poll listener not called - Stack Overflow
Your concrete problem is caused because you've turned off ajax by ajax="false". This will create a synchronous form submit which makes it impossible to fire an ajax request along. If you remove ajax="false", then it will likely work, but you've still a race condition if the one method depends on the result of the other. It's not defined which one would be executed first.
Better just use a single command component. You can use action and actionListener together. The action is intented for business actions. The actionListener is intented for preparing of business actions. If you need more action listeners, just nest a <f:actionListener> or perhaps a <f:setPropertyActionListener>.
<p:commandButton
Thanks Balus..I have tried by removing off ajax but it did not worked.
I also tried with single command component that you have suggested,but in this approach it is executing correlation method first followed by execute method..But I want to execute both methods at the same time not one by one...So is there any other way to execute both methods at the same time?
Why exactly would you want to do that? Do you realize that you need 2 threads for that? The above answer just executes the both methods in 1 enduser interaction.
Yes exactly..I need to threads that will run in parallel..But before implementing threading I am looking for some other option..How to run two bean methods simultaneously in JSF without implementing Threading.
Actually the problem is If I marge these two methods and create a single bean method that executes after click on submit button..it takes too much time to execute and load the xhtml page.To minimize this loading and execution time I converted this single method in two different methods.
jsf 2 - Call multiple bean method in primefaces simultaneously - Stack...
I had also problems with non-triggering commandButtons. In my case ajax and non-ajax reqeuests didn't work. 1. as described above - be sure to delete all form's in form's. easy done with composite usage. 2. if you have several buttons, try to use the flag "process". Helped in my case.
<p:commandButton
process="txtComment, @this" executes the setter method of inputText with id txtComment and the commandButton method.
jsf 2 - PrimeFaces CommandButton Action not called inside Composite - ...
<p:selectOneMenu <f:selectItems <f:ajax </p:selectOneMenu>
Or you can provide panel id or datatable id ,if you dont want torender the whole form, like:
<f:ajax
jsf 2 - How do I get PrimeFaces
to call valueChangeL...
RemoteCommand is a nice way to achieve that because it provides you a JavaScript function that does the stuff (calling backing bean, refreshing, submitting a form etc., everything that command link can do).
<p:remoteCommand <script type="text/javascript"> function customFunction() { //your custom code increment(); //makes a remote call } </script>
ajax - Using Primefaces JavaScript to call a JSF method on a bean on t...
<f:ajax
with
<p:ajax
And in general don't use f:ajax with primefaces components
jsf 2 - ajax call breaks primefaces calendar component - Stack Overflo...
<h:outputText <p:inputText <f:ajax </p:inputText>
jsf 2 - Fail to update h:outputText tag with (Primefaces) p:ajax call ...
Not when using native JSF or PrimeFaces. Your best bet would be to hook on session expiration instead.
If you happen to use the JSF utility library OmniFaces, then you can use its @ViewScoped. This will call the @PreDestroy when leaving the page referencing the view scoped bean.
import javax.inject.Named; import org.omnifaces.cdi.ViewScoped; @Named @ViewScoped public class Bean implements Serializable { @PreDestroy public void destroy() { // Your code here. } }
Under the covers, it works by triggering a navigator.sendBeacon() during the window beforeunload event with a fallback to synchronous XHR (which is deprecated in modern browsers supporting navigator.sendBeacon()).
Is there a way to call a method upon leaving a page with JSF or PrimeF...
What I've typically done is put a hidden p:commandLink on the page, then have Javascript call the click() event on it.
<p:commandLink
$('#hiddenLink').click();
Depends on whether those parameters are fixed or need to be adjusted client-side via javascript as well. If they don't change, you can use f:attribute. If they might change client-side, I've used h:inputHidden elsewhere on the form to push those along to the managed bean.
In my case, the element from <p:commandLink is NOT given the id "hiddenLink". Instead, it is given the id "j_idt5:hiddenLink". Therefore, I cannot find it.
ajax - Using Primefaces JavaScript to call a JSF method on a bean on t...
To rerun a script, simply re-render the tag that calls it. Assuming the form is re-rendered whenever it is "updated", this will do:
<script> function init () { $("#myspan").doSomething; } </script> <h:form <script type="text/javascript">init()</script> <span id="myspan" /> </h:form>
jsf - Automatically call javascript on update of some component in Pri...
You should not call any Expression Language directly into a non-JSF component. What you're looking for is for an <h:commandLink> instead:
<h:form> <h:commandLink <span style="...">logout</span> </h:commandLink> </h:form>
Where foo is a CSS class where you clear the default formatting for an <a>. Then, you can use the common HTML <span> component to apply the desired CSS to your logout text.
JSF/Primefaces span onClick automatically calls Backing Bean - Stack O...
If you use omnifaces @ViewScoped annotation in the backing bean the bean object is destroyed when you leave the view; so you can call a function when this happens using the @PreDestroy annotation in it.
Note: You must use omnifaces @ViewScoped annotation; with standard JSF @ViewScoped annotation the object isn't destroyed just by leaving the view, so pay attention to the import! | https://recalll.co/app/?q=jsf%202%20-%20Primefaces%20Lightbox%3A%20How%20to%20call%20hide%28%29-method%20-%20Stack%20Overflow | CC-MAIN-2019-43 | refinedweb | 2,228 | 65.62 |
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