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Python : The title to this may be confusing , but basically I want to be able to do the following : Expected behavior would be that it would open up a python terminal session , then open up xkcd comic 353 , print 'this is so meta ' to the command line , and finally exit the python command line.Basically , I want to be ... | Input python commands on the python command line |
Python : I tried to stress my server a little , and something weird happened . I 'm using mod_wsgi , with basic script plugged in : I tried to stress it a little with simple `` hit it all I can '' : And weird thing happened - wget thrown at me reports about error 500 on server.when I checked out apache logs , this is w... | mod_wsgi fails under pressure |
Python : My script loops through each line of an input file and performs some actions using the string in each line . Since the tasks performed on each line are independent of each other , I decided to separate the task into threads so that the script does n't have to wait for the task to complete to continue with the ... | What is the safest way to queue multiple threads originating in a loop ? |
Python : I have a Python pandas DataFrame in which each element is a float or NaN . For each row , I will need to find the column which holds the nth number of the row . That is , I need to get the column holding the nth element of the row that is not NaN . I know that the nth such column always exists.So if n was 4 an... | For each row , what is the fastest way to find the column holding nth element that is not NaN ? |
Python : I 've got a problem with removing \n in my program here is the code tried using .rstrip and other variants but it does nothing for my , this is the result i getthe problem is when i call children [ `` Patricia '' ] i get [ ] , because it recognizes only children [ `` Patricia\n '' ] <code> with open ( filename... | removing \n in dictionary |
Python : a follow-up question on this question : i ran the code below on python 3.5 and python 3.6 - with very different results : as stated in the previous question this raises TypeError : type object got multiple values for keyword argument ' b'on python 3.6. but on python 3.5 i get the exception : KeyError : 0moreov... | In-place custom object unpacking different behavior with __getitem__ python 3.5 vs python 3.6 |
Python : I receive next warning using SciPy fmin_bfgs ( ) optimization in the NeuralNetwork . Everything should be clear and simple , following Backpropagation algorithm.1 Feed Forward training examples.2 Calculate Error term for each Unit.3 Accumulate gradient ( for the first example , I 'm skipping regularization ter... | SciPy optimization Warning in the Neural Network |
Python : I 'm playing with django ( I 'm a quite new beginner ) and while surfing the web I read it could be possible to keep our internal camelCase naming conventions inside the mySQL database and also for the models ' name inside models.pyWell , after some days I can conclude it 's better to leave things as they were... | Django migration with `` -- fake-initial '' is not working if AddField referes to `` same '' column |
Python : Hi i have written regex to check where ther string have the char like - or . or / or : or AM or PM or space .The follworig regex work for that but i want to make case fail if the string contain the char other than AMP .import reOutput : Edited : Validate ( { 'Date ' : '12122010 ' } ) Date 12122010 False ( Expe... | Regex to check date |
Python : Retrieving the order of key-word arguments passed via **kwargs would be extremely useful in the particular project I am working on . It is about making a kind of n-d numpy array with meaningful dimensions ( right now called dimarray ) , particularly useful for geophysical data handling.For now say we have : Wh... | How to retrieve the original order of key-word arguments passed to a function call ? |
Python : I feel like I want an `` Everything '' keyword in Python that would have the following properties : Any boolean test of the form x in Everything would always return True , regardless of x.Any attempt to iterate it , such as for x in Everything would raise an exceptionMy motivation is that I would like to have ... | A Python `` Everything '' keyword that always returns True for membership tests |
Python : I find myself often wanting to structure my exception classes like this : I have only seen this pattern used in Django ( DoesNotExist ) and it makes so much sense . Is there anything I 'm missing , why most people seem to favor top-level Exceptions ? editI would use these classes for versatile granularity , e.... | Are python Exceptions as class attributes a bad thing ? |
Python : I am working on fitting statistical models to distributions using matplotlib 's hist function . For example my code fits an exponential distribution using the following code : Which runs fine , but when I modify it to do the same thing for a uniform distribution between a & b , The code crashes , with ValueErr... | What specific requirements does the function passed to scipy.optimize.curve_fit need to fulfill in order to run ? |
Python : I have created a form widget that is automatically adding a add new record section at the top of the form , which i do not want to be there . can someone tell me how to disable this ? I just want to display the variables not the add form.forms.pyadmin.pychange_view.htmlpage that is loaded : <code> class Templa... | Django - Remove add new record from form widget > |
Python : such asI want to know , when does python combine the constant string as the CONST.If possible , please tell me which source code about this at cpython ( whatever 2.x , 3.x ) . <code> In [ 9 ] : dis.disassemble ( compile ( `` s = '123 ' + '456 ' '' , `` < execfile > '' , `` exec '' ) ) 1 0 LOAD_CONST 3 ( '12345... | When does python compile the constant string letters , to combine the strings into a single constant string ? |
Python : I want to define constraint specification language based on Python . For example : Here IntVar is a class describing a variable that can assume any integer value , and Constraint is a class to represent constraints . To implement this I can just overload operator < by defining method __lt__ for class IntVar.Su... | Defining new semantics for expressions in Python |
Python : Could n't really find it , but probably it 's me not knowing how to search properly : ( Just wanted to find out what the name is for : type of construct ? <code> [ x for x in some_list ] | What is the name for [ x for x in some_list ] type of construct in python ? |
Python : I understand that one way to work with the digits of a number in Python is to convert the number to a string , and then use string methods to slice the resulting `` number '' into groups of `` digits '' . For example , assuming I have a function prime that tests primality , I can confirm that an integer n is b... | Is using ` str ` the correct idiom for working with digits in Python |
Python : I am trying to use Mutagen for changing ID3 ( version 2.3 ) cover art for a bunch of MP3 files in the following way : However , the file ( or at least the APIC tag ) remains unchanged , as checked by reading the tag back . In the system file explorer , the file does show an updated Date modified , however . Ho... | Mutagen 's save ( ) does not set or change cover art for MP3 files |
Python : Consider the following list of day-of-week-hour pairs in 24H format : and two time points , e.g . : Start : End : Say we need to know how many hours there are between these two datetimes ( either rounding up or down ) for each of the day-of-week-hour pairs specified above.How can I approach this problem in Pyt... | Counting day-of-week-hour pairs between two dates |
Python : I started learning how to use theano with lasagne , and started with the mnist example . Now , I want to try my own example : I have a train.csv file , in which every row starts with 0 or 1 which represents the correct answer , followed by 773 0s and 1s which represent the input . I did n't understand how can ... | numpy array from csv file for lasagne |
Python : I 'd like to add a polynomial curve to a scatter plot that is rendered using a callback.Following is my callback function which returns the scatter plot.Resulting plot : I am able to add a polyfit line using sklearn.preprocessing.Is there a way to do this in plotly ? <code> @ app.callback ( Output ( 'price-gra... | Plotly : How to add polynomial fit line to plotly go.scatter figure using a DASH callback ? |
Python : Lets assume I have a ( text ) file with the following structure ( name , score ) : And so on . My aim is to sum the scores for every name and order them from highest score to lowest score . So in this case , I want the following output : In advance I do not know what names will be in the file.I was wondering i... | Efficiently processing data in text file |
Python : In the python idle : But when I put the code in a script and run it , I will get a different result : Why did this happen ? I know that is compares the id of two objects , so why the ids of two objects are same/unique in python script/idle ? I also found that , if I use a small int , for example 1 , instead of... | Different behavior in python script and python idle ? |
Python : I want to run tests with multiple builds of a product running them once . Here is example of the code : The first iteration works well , but on the start of the second one an error appears : What is happening ? What result runner calls ? And why does it fail ? Any ideas how to solve the problem ? <code> import... | How to run the same TestSuite multiple times unittest texttestrunner |
Python : I was looking into how Python represents string after PEP 393 and I am not understanding the difference between PyASCIIObject and PyCompactUnicodeObject.My understanding is that strings are represented with the following structures : Correct me if I am wrong , but my understanding is that PyASCIIObject is used... | Python > = 3.3 Internal String Representation |
Python : Using Spacy , I extract aspect-opinion pairs from a text , based on the grammar rules that I defined . Rules are based on POS tags and dependency tags , which is obtained by token.pos_ and token.dep_ . Below is an example of one of the grammar rules . If I pass the sentence Japan is cool , it returns [ ( 'Japa... | Named Entity Recognition in aspect-opinion extraction using dependency rule matching |
Python : I am trying to implement a NaN-safe shuffling procedure in Cython that can shuffle along several axis of a multidimensional matrix of arbitrary dimension.In the simple case of a 1D matrix , one can simply shuffle over all indices with non-NaN values using the Fisher–Yates algorithm : I would like to extend thi... | In-place shuffling of multidimensional arrays |
Python : I am trying to create f-distributed random numbers with given degree of freedoms d1 and d2 , and plot both a histogram with f-distributed random numbers , and plot an idealised f-distribution curve , but when I give small values to df 's , the histogram does not show up . I am new at statistics and matplotlib ... | Histogram does not show up in f-distribution plot |
Python : When reading the book 'Effective Python ' by Brett Slatkin I noticed that the author suggested that sometimes building a list using a generator function and calling list on the resulting iterator could lead to cleaner , more readable code.So an example : Where a user could callorand get the same result.The sug... | Is it efficient to build a list with a generator function |
Python : In python : <code> > > > a = b or { } | What is the official name of this construct ? |
Python : I have an autobahn Websocket Server with the typical onX functions in it 's protocol . My problem is that I ca n't find a way to exit onX , while keep doing the various stuff that I wanted to do when the specific message arrived . More specifically in my onMessage function , I sometimes perform an HTTP request... | Autobahn , leave onMessage block |
Python : I have : and then I get an error : If I set the two sizes to be the same , then the error goes away . But I 'm wondering if my input_size is some large number , say 15 , and I want to reduce the number of hidden features to 5 , why should n't that work ? <code> def __init__ ( self , feature_dim=15 , hidden_siz... | With a PyTorch LSTM , can I have a different hidden_size than input_size ? |
Python : I have a buffer object in C++ that inherits from std : :vector < char > . I want to convert this buffer into a Python string so that I can send it out over the network via Twisted 's protocol.transport.write.Two ways I thought of doing this are ( 1 ) making a string and filling it char by char : and ( 2 ) maki... | Python buffer copy speed - why is array slower than string ? |
Python : I am aware that regular queryset or the iterator queryset methods evaluates and returns the entire data-set in one shot .for instance , take this : QuestionIn both methods all the rows are fetched in a single-go.Is there any way in djago that the queryset rows can be fetched one by one from database.Why this w... | Fetching queryset data one by one |
Python : After encountering some probable memory leaks in a long running multi threaded script I found out about maxtasksperchild , which can be used in a Multi process pool like this : Is something similar possible for the Threadpool ( multiprocessing.pool.ThreadPool ) ? <code> import multiprocessingwith multiprocessi... | Is it possible to set maxtasksperchild for a threadpool ? |
Python : My project looks like this : The contents of the .py files are shown below : main.pyc/run_project.pyc/z/the_module.pyc/z/y/the_module_module.pyc/z/y/the_support_function.pyGitHub repo to make replication easier : running-pycharm-project-at-cmdThe problem : in Pycharm load up the project with running-pycharm-pr... | How do I replicate the way PyCharm is running my Python 3.4 project at the command line ? |
Python : I have made a small script in Python to solve various Gym environments with policy gradients.What should be passed backwards to calculate the gradients ? I am using gradient ascent but I could switch it to descent . Some people have defined the reward function as totalReward*log ( probabilities ) . Would that ... | What Loss Or Reward Is Backpropagated In Policy Gradients For Reinforcement Learning ? |
Python : Simple repro : This question has an effective duplicate , but the duplicate was not answered , and I dug a bit more into the CPython source as a learning exercise . Warning : i went into the weeds . I 'm really hoping I can get help from a captain who knows those waters . I tried to be as explicit as possible ... | Why does setting a descriptor on a class overwrite the descriptor ? |
Python : With SQLAlchemy , I 'm finding that sometimes I mis-type a name of an attribute which is mapped to a column , which results in rather difficult to catch errors : Is there a way to configure the mapped class so assigning to anything which is not mapped to an SQLAlchemy column would raise an exception ? <code> c... | How do I raise an exception when assigning to an attribute which is NOT mapped to an SQLAlchemy column ? |
Python : I am running to of the following programs . Importantly , imagine that there is mymodule.py file in the directory where both these programs are located.The first : The second : The first snippet raises ImportError as expected ( after all , the directory where mymodule is located is not in path ) . The second s... | Difference between exec behavior when module is imported or not |
Python : I was looking at the source code for the built-in argparse._AppendAction , which implements the `` append '' action , and puzzled over the way it is implemented : To break it down : _ensure_value is like dict.setdefault for attributes . That is , if namespace has an attribute with the name self.dest then it is... | Please explain reasoning behind code snippet from argparse module |
Python : Reading the Django docs , it advices to make a custom creation method for a model named Foo by defining it as create_foo in the manager : My question is that why is the previous one preferred to simply overriding the base class 's create method : Imo it seems that only overriding create will prevent anyone fro... | Why define create_foo ( ) in a Django models.Manager instead of overriding create ( ) ? |
Python : I 'm trying to use the __defaults__ attribute of a function object to get default values for arguments . It works for this case : but for this it does n't : Why does test.__defaults__ contain None ? How can I get the default value for the parameter in this case ? <code> > > > def test ( x , y=1 ) : pass ... > ... | How can I access the default value for a keyword argument in Python ? |
Python : I have created a simple custom MultiValueField and MultiWidget for the purpose of entering a date of birth but allowing separate entry of the day , month and year . The rationale is that the app is for entry of historical data , so one or more of these fields could be unknown . There is also a checkbox that di... | Django Custom MultiWidget Retaining Old Values |
Python : Using the snippet below , I have added tab completion to the python interpreter.However , I have encountered a weird behaviour where after hitting TAB , the interpreter would give duplicates as such:108 possibilities ! min 2 , max 4 duplicates.Furthermore , if I subclass dict the total number of possibilities ... | Duplicate output on Python tab completion ( OsX 10.8 ) |
Python : Using MySQL , I am trying to have a table with a composite key of multiple fields.The issue is that some of the fields are large ( 255 - 1024 length ) , if I try to run the migration , I will get : Instead of increasing the DB 's key length ( or changing some other DB / table settings ) , I found out that I ca... | Django - limit key size on unique_together columns |
Python : I have a array of identifiers that have been grouped into threes . For each group , I would like to randomly assign them to one of three sets and to have those assignments stored in another array . So , for a given array of grouped identifiers ( I presort them ) : A possible output would beUltimately , I would... | Permutations over subarray in python |
Python : I used shap to determine the feature importance for multiple regression with correlated features . shap offers a chart to get the shap values . Is there also a statistic available ? I am interested in the exact shap values . I read the Github repository and the documentation but I found nothing regarding this ... | Shap statistics |
Python : if the customer sign in and he has permission to see the data that the admin has given to him , he will see the data after he sign in , but if the admin does n't give him permission , this message will appear You are not authorized to view this pagein my case no matter what the permission given the admin this ... | Django Group permission how to print it in template |
Python : The docs say that : Each class keeps a list of weak references to its immediate subclasses . This method returns a list of all those references still alive . But how does each class obtain a list of weak references to its subclasses in the first place ? In other words , when I createhow does A find out that B ... | How is __subclasses__ method implemented in CPython ? |
Python : I 'm getting desperate because I ca n't seem to find a solution for what I thought would be used by everyone out there.I want to test a simple login with selenium and pytest with a live_server url . According to pytest-django doc , a simple fixture called live_server should do the trick ( https : //pytest-djan... | Selenium login test does n't accept pytest fixtures for login or refuses to connect |
Python : I have a Python package that only runs on Python 2 . It has the following classifiers in its setup.py : However , if I create a virtualenv with Python 3 , pip happily installs this package.How do I prevent the package being installed ? Should my setup.py throw an error based on sys.version_info ? Can I stop pi... | How do I mark a Python package as Python 2 only ? |
Python : Set-upI 'm using PyDrive 2.0 to connect to the Google Drive API.The working directory /Users/mypath/access_google_drive contains the client_secrets.json , which looks like , where I replaced the real client_id and client_secret with xxx.IssueWhen the browser ( Safari 14.0 ) shows Gdrive api link wants to acces... | PyDrive 2.0 – AuthenticationError : No code found in redirect |
Python : I want a code that deletes all instances of any number that has been repeated from a list.E.g . : I have tried to remove the duplicated elements in the list already ( by using the `` unique '' function ) , but it leaves a single instance of the element in the list nevertheless ! I went through a lot of StackOv... | How to delete all instances of a repeated number in a list ? |
Python : I 've been working on some Python code to be able to get links to social media accounts from government websites , for a research into ease with which municipalities can be contacted . I 've managed to adapt some code to work in 2.7 , which prints all links to facebook , twitter , linkedin and google+ present ... | Using multiple web pages in a web scraper |
Python : I would like to handle a NameError exception by injecting the desired missing variable into the frame and then continue the execution from last attempted instruction.The following pseudo-code should illustrate my needs.Read the whole unittest on repl.it NotesAs pointed out by ivan_pozdeev in his answer , this ... | How to continue a frame execution from last attempted instruction after handling an exception ? |
Python : Consider a sequence of coin tosses : 1 , 0 , 0 , 1 , 0 , 1 where tail = 0 and head = 1.The desired output is the sequence : 0 , 1 , 2 , 0 , 1 , 0Each element of the output sequence counts the number of tails since the last head.I have tried a naive method : Question : Is there a better method ? <code> def time... | Count number of tails since the last head |
Python : I have login history data from User A for a day . My requirement is that at any point in time the User A can have only one valid login . As in the samples below , the user may have attempted to login successfully multiple times , while his first session was still active . So , any logins that happened during t... | Compare current row value to previous row values |
Python : This question is spurred from the answers and discussions of this question . The following snippet shows the crux of the question : The questions I have are the following : Why was it decided that the bool value of NotImplemented should be True ? It feels unpythonic.Is there a good reason I am unaware of ? The... | Why is NotImplemented truthy in Python 3 ? |
Python : I have the following Pandas dataframe : and the following dict : I would now like to map all the entries in the lists in my dataframe using the dictionary . The result should be the following : How can this be done most efficiently ? <code> 1 [ `` Apple '' , `` Banana '' ] 2 [ `` Kiwi '' ] 3 None4 [ `` Apple '... | Convert elements of list in pandas series using a dict |
Python : I am working with an ORM that accepts classes as input and I need to be able to feed it some dynamically generated classes . Currently , I am doing something like this contrived example : While this works fine , it feels off by a bit : for example , both classes print as < class '__main__.Cls ' > on the repl .... | What is the least-bad way to create Python classes at runtime ? |
Python : How to terminate loop.run_in_executor with ProcessPoolExecutor gracefully ? Shortly after starting the program , SIGINT ( ctrl + c ) is sent.With max_workers equal or lesser than the the number of tasks everything works . But if max_workers is greater , the output of the above code is as follows : I would like... | How to terminate loop.run_in_executor with ProcessPoolExecutor gracefully ? |
Python : I need to find the intersection of a GeoDataFrame with itself through geopandas in QGIS . The code works perfectly in the Anaconda environment but it fails in the QGIS python.Shapefile is available at below link : https : //drive.google.com/file/d/1DQqg7Cf6AokyadkmOE8Y6k41tqDMXdmS/view ? usp=drivesdk Below is ... | geopandas overlay ( ) function not working in QGIS |
Python : I have a codebase where I 'm cleaning up some messy decisions by the previous developer . Frequently , he has done something like : ... This , of course , pollutes the name space and makes it difficult to tell where an attribute in the module is originally from.Is there any way to have Python analyze and fix t... | Reversing from module import * |
Python : I 'm working on a Python project where a previous developer placed a large portion of the code in the base __init__.py file . I would like to be able to move code out of the file to a new file in a subdirectory.So importing the spam module would use the code in foobar/eggs.py.I would like to keep 100 % compati... | Moving code out of __init__.py but keeping backwards compatibility |
Python : I want to make forward forecasting for monthly times series of air pollution data such as what would be 3~6 months ahead of estimation on air pollution index . I tried scikit-learn models for forecasting and fitting data to the model works fine . But what I wanted to do is making a forward period estimate such... | any workaround to do forward forecasting for estimating time series in python ? |
Python : Possible Duplicate : Do python 's variable length arguments ( *args ) expand a generator at function call time ? Let 's say you have a function like this : And you call it like that : Will the elements be called lazily or will the generator run through all the possibly millions of elements before the function ... | Are *parameters calls lazy ? |
Python : Given this file : http : //mtarchive.geol.iastate.edu/2019/02/18/mrms/ncep/GaugeCorr_QPE_01H/GaugeCorr_QPE_01H_00.00_20190218-150000.grib2.gz… I get different output depending on the software I use.andboth output : However : outputs -3 for all 24,500,000 records.I get the same result if I parse the file using ... | Possible bug in GDAL ? |
Python : Trying to find an efficient way to extract all instances of items in an array out of another.For exampleArray 1 is an array of items that need to be extracted out of array 2 . Thus , array 2 should be modified to [ `` 456 '' , `` 789 '' ] I know how to do this , but no in an efficient manner . <code> array1 = ... | Using arrays with other arrays in Python |
Python : I need to sum all the numbers in the list . If 0 occurs start subtracting , until another 0 , start adding . For example : This is what I 've tried : <code> [ 1 , 2 , 0 , 3 , 0 , 4 ] - > 1 + 2 - 3 + 4 = 4 [ 0 , 2 , 1 , 0 , 1 , 0 , 2 ] - > -2 - 1 + 1 - 2 = -4 [ 1 , 2 ] - > 1 + 2 = 3 [ 4 , 0 , 2 , 3 ] = 4 - 2 - ... | Sum numbers in a list but change their sign after zero is encountered |
Python : I just started learning Python and I 'm confused about this example : If to was initialized once , would n't to not be None the 2nd time it 's called ? I know the code above works but ca n't wrap my head around this `` initialized once '' description . <code> def append_to ( element , to=None ) : if to is None... | Python default params confusion |
Python : Does unit test library for python ( especially 3.x , I do n't really care about 2.x ) has decorator to be accessed only by root user ? I have this testing function.blabla function can only be executed by root . I want root user only decorator so normal user will skip this test : Does such decorator exist ? We ... | Unit test for only root user in python |
Python : Sorry for the badly explained title . I am trying to parallelise a part of my code and got stuck on a dot product . I am looking for an efficient way of doing what the code below does , I 'm sure there is a simple linear algebra solution but I 'm very stuck : <code> puy = np.arange ( 8 ) .reshape ( 2,4 ) puy2 ... | Numpy Dot Product of two 2-d arrays in numpy to get 3-d array |
Python : I try to create a kivy widget from Scatter , which is freely zoomable , but once the mouse button is lifted falls back to the closest zoom level . It works , but it does not update the zoom until the next click . I think I need to bind some event here , but I 'm pretty new to kivy and can not figure it out . H... | Modified kivy scatter widget does not update transformation |
Python : Code : Here , I try to replace all the occurrences of 'abc ' with 'XXX ' . Is there a shorter way to do this ? <code> > > > mylist = [ 'abc ' , 'def ' , 'ghi ' ] > > > mylist [ 'abc ' , 'def ' , 'ghi ' ] > > > for i , v in enumerate ( mylist ) : ... if v=='abc ' : ... mylist [ i ] = 'XXX ' ... > > > mylist [ '... | Replacing particular elements in a list |
Python : Is it possible to merge strings that start with ' ( ' and end with ' ) ' and then reinsert it into the same list or a new list ? My desired output poke_list = [ ... 'Charizard ( Mega Charizard X ) ' , '78 ' , '130 ' , ... ] <code> poke_list = [ ... 'Charizard ' , ' ( Mega ' , 'Charizard ' , ' X ) ' , '78 ' , '... | How to join strings between parentheses in a list of strings |
Python : An error is raised when I try to set the value of an argument of a class who inherits from str . The error occurs only when I try to access the argument with myClass ( arg = 'test ' ) . The error is : The issue is shown in this exemple : Only the last line raises the error . The previous line works well.The pr... | Set the value of an argument in a class who inherits from int or float or str |
Python : I want to search a list of strings ( having from 2k upto 10k strings in the list ) in thousands of text files ( there may be as many as 100k text files each having size ranging from 1 KB to 100 MB ) saved in a folder and output a csv file for the matched text filenames.I have developed a code that does the req... | How to make searching a string in text files quicker |
Python : My project structure seems to be correct . File script1.py imports script2.py using 'import script2'.I can run code without errors with following commands : Unfortunately , when I try to execute tests using pytest or python -m pytest I get error that there 's no module named script2 ( full message below ) . I ... | ModuleNotFoundError for import within the same package while using pytest |
Python : Haskell : Python : It should output the next two values of the list , e.g . 5.0 , 3.4But it outputs 5.0 twice , why ? <code> average x y = ( x + y ) / 2sqrt ' : : ( Ord a , Fractional a ) = > a - > Int - > asqrt ' 0 _ = 0.0sqrt ' 1 _ = 1.0sqrt ' s approximations = ( infsqr ' s ) ! ! approximationsinfsqr ' n = ... | Why does n't this Haskell I translated to Python work properly ? |
Python : I have a directed tree , and I would like to get its size . I have no information about its depth or distribution of nodes . There are two major obstacles:1 ) The tree is very large ( ~billions of nodes ) 2 ) Edge traversal is expensive.Are there statistical methods I can use to get an estimate of its size ( n... | Statistic estimation of total nodes in a tree where edge traversal is expensive |
Python : I have the following example dataframe : which creates this dataframe : I am trying to `` unmelt '' though not exactly the source and test columns into new dataframe Columns such that it will look like this : It 's my understanding that pivot and melt will do the entire DisplayLabel column and not just some of... | Unmelt only part of a column from pandas dataframe |
Python : I 'm creating several classes to use them as state flags ( this is more of an exercise , though I 'm going to use them in a real project ) , just like we use None in Python , i.e.NoneType has several special properties , most importantly it 's a singleton , that is there ca n't be more than one NoneType instan... | Mimic Python 's NoneType |
Python : In a program that I 'm writing , I wanted to make a ConfigParser that 's read only so that it can safely be used globally . I did n't realize this , but apparently the SafeConfigParser is an old-style class , thus I had to subclass it like this : If I did n't use object as a mixin , the call to SafeConfigParse... | Is it safe to make an old-style class into a new-style class using Multiple Inheritance ? |
Python : I have made a multiplayer Pong game with TCP , UDP and pygame.the modules i 'm using are : pygame , os , logging , threading , random , yaml ( PyYAML ) and socketWhen running the game from the commandline with python2.7 it works well , but the compiled version with py2app gives me a error which is : I have goo... | Game runs well from source , but not from py2app |
Python : I need to write XML files using lxml and Python.However , I ca n't figure out whether to use a class to do this or a function . The point being , this is the first time I am developing a proper software and deciding where and why to use a class still seems mysterious.I will illustrate my point.For example , co... | Confused as to use a class or a function : Writing XML files using lxml and Python |
Python : I 'm trying to write a binary translator - with a string as an input and its binary representation as output.And I 'm having some difficulties , I wrote in variable the translation for each letter , but they are variables , not strings , so I want to take an input from that matches with the name of the variabl... | Text to Binary in Python |
Python : I have an irregularly spaced ( with respect to time frequency ) pandas data frame . I can successfully up-sample the data frame to a daily frequency using the resample command , however my problem is that the resampling ends at the last ( pre-resampled ) data observation . I would like the resampling to span a... | How to resample irregular time series to daily frequency and have it span to today ? |
Python : I have a script that can re-write a Python module so that all occurrences of func ( a ) are transfored to func2 ( a is None ) . I now want to support also func ( a , msg ) becoming func2 ( a is None , msg ) , but I ca n't find the pattern that will do this . This following shows my attempt : For each func foun... | pattern to match 1-or-2-arg function call for lib2to3 |
Python : I have this neural network that I 've trained seen bellow , it works , or at least appears to work , but the problem is with the training . I 'm trying to train it to act as an OR gate , but it never seems to get there , the output tends to looks like this : I have this loss graph : Its strange it appears to b... | Neural network backprop not fully training |
Python : I am trying to merge several DataFrames based on a common column . This will be done in a loop and the original DataFrame may not have all of the columns so an outer merge will be necessary . However when I do this over several different DataFrames columns duplicate with suffix _x and _y . I am looking for one... | Merge DataFrames in Python without duplicating columns |
Python : I 'm writing a simple string parser which allows regexp-like quantifiers . An input string might look like this : My parser function translates this string to a list of tuples : Now , the tricky bit is that I need a list of all valid combinations that are specified by the quantification . The combinations all ... | More elegant way to implement regexp-like quantifiers |
Python : Say I have a decorator which causes the function to print out any exceptions and return None , if an exception happens , instead of failing . Assuming this is a good idea , what 's the preferred naming style ? a ) b ) That is : should it a ) be a command ( the decorator tells the function to do something diffe... | python : should decorator names be actions or descriptions ? |
Python : I am trying to extract all slices of length 4 along 0th axis of a 2-dim tensor . So far I can do it mixing pure Python with tensorflow.What would be an efficient way of doing that without using pure Python ? Note that the `` test '' array is actually supposed to be a tensor , thus its shape is n't known before... | How to efficiently extract all slices of given length using tensorflow |
Python : I 'm storing contacts between different elements . I want to eliminate elements of certain type and store new contacts of elements which were interconnected by the eliminated element.Problem backgroundImagine this problem . You have a water molecule which is in contact with other molecules ( if the contact is ... | Refining data stored in SQLite - how to join several contacts ? |
Python : I have a custom environment in keras-rl with the following configurations in the constructorAs you can see , my agent will perform 3 actions , depending on the action , a different reward will be calculated in the function step ( ) below : The problem is the fact that , if I print the actions at every episode ... | Define action values in keras-rl |
Python : QNetworkAccessManager can do requests asynchronously , and time.sleep ( secs ) can suspend the execution for the given number of seconds . I was confused by the code below . Is t2 here always greater than 10 seconds ? Without using time.sleep ( secs ) in the code here , the finished slot getWebPageSRC was call... | can time.sleep ( secs ) suspend QNetworkAccessManager does request asynchronously ? |
Python : I need to get a calculation of some data so , in annotate I put some maths logic with other field but whenever there is 0 it is throwing an error . I need to handle that error in annotate . My code looks like this : In total_billable , there is total_billable_leads variable which may have Zero ( 0 ) then on a ... | Throwing ZeroDivisionError |
Python : Here is what I am looking at : I know that int in Python is growable ( can get bigger that 24 bytes ) objects that live on the heap , and I see why that object can be quite large , but is n't a list just a collections of such objects ? Apparently it is not , what is going on here ? <code> In [ 1 ] : import sys... | Why is single int 24 bytes , but in list it tends to 8 bytes |
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