task_url stringlengths 30 116 | task_name stringlengths 2 86 | task_description stringlengths 0 14.4k | language_url stringlengths 2 53 | language_name stringlengths 1 52 | code stringlengths 0 61.9k |
|---|---|---|---|---|---|
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Inform_7 | Inform 7 | X is a room |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #PureBasic | PureBasic | #TESTSTR="1223334444"
NewMap uchar.i() : Define.d e
Procedure.d nlog2(x.d) : ProcedureReturn Log(x)/Log(2) : EndProcedure
Procedure countchar(s$, Map uchar())
If Len(s$)
uchar(Left(s$,1))=CountString(s$,Left(s$,1))
s$=RemoveString(s$,Left(s$,1))
ProcedureReturn countchar(s$, uchar())
EndIf
EndProced... |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #Limbo | Limbo | implement Ethiopian;
include "sys.m";
sys: Sys;
print: import sys;
include "draw.m";
draw: Draw;
Ethiopian : module
{
init : fn(ctxt : ref Draw->Context, args : list of string);
};
init (ctxt: ref Draw->Context, args: list of string)
{
sys = load Sys Sys->PATH;
print("\n%d\n", ethiopian(17, 34, 0));
prin... |
http://rosettacode.org/wiki/Euler%27s_sum_of_powers_conjecture | Euler's sum of powers conjecture | There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin.
Euler's (disproved) sum of powers conjecture
At least k positive kth powers are required to sum to a kth power,
except for the trivial case... | #SenseTalk | SenseTalk | findEulerSumOfPowers
to findEulerSumOfPowers
set MAX_NUMBER to 250
set possibleValues to 1..MAX_NUMBER
set possible5thPowers to each item of possibleValues to the power of 5
repeat for x0 in 1..250
repeat for x1 in 1..x0
repeat for x2 in 1..x1
repeat for x3 in 1..x2
... |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #Racket | Racket | (define (factorial n)
(if (= 0 n)
1
(* n (factorial (- n 1))))) |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #Maple | Maple | EvenOrOdd := proc( x::integer )
if x mod 2 = 0 then
print("Even"):
else
print("Odd"):
end if:
end proc:
EvenOrOdd(9); |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | EvenQ[8] |
http://rosettacode.org/wiki/Emirp_primes | Emirp primes | An emirp (prime spelled backwards) are primes that when reversed (in their decimal representation) are a different prime.
(This rules out palindromic primes.)
Task
show the first twenty emirps
show all emirps between 7,700 and 8,000
show the 10,000th emirp
In each list, the numbe... | #Scheme | Scheme | ; Primality test by simple trial division.
(define prime?
(lambda (num)
(if (< num 2)
#f
(let loop ((div 2))
(cond ((> (* div div) num) #t)
((zero? (modulo num div)) #f)
(else (loop (1+ div))))))))
; Check if number is an emirp prime.
(define emirp?
(lambda (num... |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #Lua | Lua |
-- create an empty string 3 different ways
str = ""
str = ''
str = [[]]
-- test for empty string
if str == "" then
print "The string is empty"
end
-- test for nonempty string
if str ~= "" then
print "The string is not empty"
end
-- several different ways to check the string's length
if string.len(str) == 0 ... |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #M2000_Interpreter | M2000 Interpreter |
A$=""
Print A$<>"", A$="", Len(A$)=0
|
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Intercal | Intercal | PLEASE GIVE UP |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Io | Io | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #J | J | '' |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #Python | Python | from __future__ import division
import math
def hist(source):
hist = {}; l = 0;
for e in source:
l += 1
if e not in hist:
hist[e] = 0
hist[e] += 1
return (l,hist)
def entropy(hist,l):
elist = []
for v in hist.values():
c = v / l
elist.append(-c... |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #Locomotive_Basic | Locomotive Basic | 10 DEF FNiseven(a)=(a+1) MOD 2
20 DEF FNhalf(a)=INT(a/2)
30 DEF FNdouble(a)=2*a
40 x=17:y=34:tot=0
50 WHILE x>=1
60 PRINT x,
70 IF FNiseven(x)=0 THEN tot=tot+y:PRINT y ELSE PRINT
80 x=FNhalf(x):y=FNdouble(y)
90 WEND
100 PRINT "=", tot |
http://rosettacode.org/wiki/Euler%27s_sum_of_powers_conjecture | Euler's sum of powers conjecture | There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin.
Euler's (disproved) sum of powers conjecture
At least k positive kth powers are required to sum to a kth power,
except for the trivial case... | #Sidef | Sidef | define range = (1 ..^ 250)
var p5 = Hash()
var sum2 = Hash()
for i in (range) {
p5{i**5} = i
for j in (range) {
sum2{i**5 + j**5} = [i, j]
}
}
var sk = sum2.keys.map{ Num(_) }.sort
for p in (p5.keys.map{ Num(_) }.sort) {
var s = sk.first {|s|
p > s && sum2.exists(p-s)
} \\ ... |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #Raku | Raku | sub postfix:<!> (Int $n) { [*] 2..$n }
say 5!; |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #MATLAB_.2F_Octave | MATLAB / Octave | isOdd = logical(bitand(N,1));
isEven = ~logical(bitand(N,1)); |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #Maxima | Maxima | evenp(n);
oddp(n); |
http://rosettacode.org/wiki/Emirp_primes | Emirp primes | An emirp (prime spelled backwards) are primes that when reversed (in their decimal representation) are a different prime.
(This rules out palindromic primes.)
Task
show the first twenty emirps
show all emirps between 7,700 and 8,000
show the 10,000th emirp
In each list, the numbe... | #Sidef | Sidef | func forprimes(a, b, callback) {
for (var p = a.dec.next_prime; p <= b; p.next_prime!) {
callback(p)
}
}
func is_emirp(p) {
var str = Str(p)
var rev = str.reverse
(str != rev) && is_prime(Num(rev))
}
func emirp_list(count) {
var i = 13
var inc = (100 + 10*count)
var n = []
... |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #Maple | Maple |
s := ""; # Create an empty string
evalb(s = ""); # test if the string is empty
evalb(s <> ""); # test if the string is not empty
|
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language |
str=""; (*Create*)
str==="" (*test empty*)
str=!="" (*test not empty*)
|
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Java | Java | public class EmptyApplet extends java.applet.Applet {
@Override public void init() {
}
} |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #JavaScript | JavaScript | |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #R | R | entropy = function(s)
{freq = prop.table(table(strsplit(s, '')[1]))
-sum(freq * log(freq, base = 2))}
print(entropy("1223334444")) # 1.846439 |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #Racket | Racket | #lang racket
(require math)
(provide entropy hash-entropy list-entropy digital-entropy)
(define (hash-entropy h)
(define (log2 x) (/ (log x) (log 2)))
(define n (for/sum [(c (in-hash-values h))] c))
(- (for/sum ([c (in-hash-values h)] #:unless (zero? c))
(* (/ c n) (log2 (/ c n))))))
(define (list-entr... |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #Logo | Logo | to double :x
output ashift :x 1
end
to halve :x
output ashift :x -1
end
to even? :x
output equal? 0 bitand 1 :x
end
to eproduct :x :y
if :x = 0 [output 0]
ifelse even? :x ~
[output eproduct halve :x double :y] ~
[output :y + eproduct halve :x double :y]
end |
http://rosettacode.org/wiki/Euler%27s_sum_of_powers_conjecture | Euler's sum of powers conjecture | There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin.
Euler's (disproved) sum of powers conjecture
At least k positive kth powers are required to sum to a kth power,
except for the trivial case... | #Swift | Swift | extension BinaryInteger {
@inlinable
public func power(_ n: Self) -> Self {
return stride(from: 0, to: n, by: 1).lazy.map({_ in self }).reduce(1, *)
}
}
func sumOfPowers(maxN: Int = 250) -> (Int, Int, Int, Int, Int) {
let pow5 = (0..<maxN).map({ $0.power(5) })
let pow5ToN = {n in pow5.firstIndex(of: n)}... |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #Rapira | Rapira | Фун Факт(n)
f := 1
для i от 1 до n
f := f * i
кц
Возврат f
Кон Фун |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #MAXScript | MAXScript | -- MAXScript : Even or Odd : N.H. 2019
-- Open the MAXScript Listener for input and output
userInt = getKBValue prompt:"Enter an integer and i will tell you if its Even or Odd : "
if classOf userInt != Integer then print "The value you enter must be an integer"
else if (Mod userInt 2) == 0 Then Print "Your number is ev... |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #Mercury | Mercury | even(N) % in a body, suceeeds iff N is even.
odd(N). % in a body, succeeds iff N is odd.
% rolling our own:
:- pred even(int::in) is semidet.
% It's an error to have all three in one module, mind; even/1 would fail to check as semidet.
even(N) :- N mod 2 = 0. % using division that truncates towards -infinity
ev... |
http://rosettacode.org/wiki/Emirp_primes | Emirp primes | An emirp (prime spelled backwards) are primes that when reversed (in their decimal representation) are a different prime.
(This rules out palindromic primes.)
Task
show the first twenty emirps
show all emirps between 7,700 and 8,000
show the 10,000th emirp
In each list, the numbe... | #Smalltalk | Smalltalk | isEmirp :=
[:p | |e|
(e := p asString reversed asNumber) isPrime
and:[ e ~= p ]
]. |
http://rosettacode.org/wiki/Emirp_primes | Emirp primes | An emirp (prime spelled backwards) are primes that when reversed (in their decimal representation) are a different prime.
(This rules out palindromic primes.)
Task
show the first twenty emirps
show all emirps between 7,700 and 8,000
show the 10,000th emirp
In each list, the numbe... | #Stata | Stata | emirp 1000
list in 1/20, noobs noh
+-----+
| 13 |
| 17 |
| 31 |
| 37 |
| 71 |
|-----|
| 73 |
| 79 |
| 97 |
| 107 |
| 113 |
|-----|
| 149 |
| 157 |
| 167 |
| 179 |
| 199 |
|-----|
| 311 |
| 337 |
| 347 |
| 359 |
| 389 |
+-----+
emirp 10000
list if 7700<p & p<... |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #MATLAB_.2F_Octave | MATLAB / Octave | % Demonstrate how to assign an empty string to a variable.
str = '';
% Demonstrate how to check that a string is empty.
isempty(str)
(length(str)==0)
% Demonstrate how to check that a string is not empty.
~isempty(str)
(length(str)>0) |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #Maxima | Maxima | s: ""$
/* check using string contents */
sequal(s, "");
not sequal(s, "");
/* check using string length */
slength(s) = "";
slength(s) # ""; |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Joy | Joy | . |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Jq | Jq | empty |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #Raku | Raku | sub entropy(@a) {
[+] map -> \p { p * -log p }, bag(@a).values »/» +@a;
}
say log(2) R/ entropy '1223334444'.comb; |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #LOLCODE | LOLCODE | HAI 1.3
HOW IZ I Halve YR Integer
FOUND YR QUOSHUNT OF Integer AN 2
IF U SAY SO
HOW IZ I Dubble YR Integer
FOUND YR PRODUKT OF Integer AN 2
IF U SAY SO
HOW IZ I IzEven YR Integer
FOUND YR BOTH SAEM 0 AN MOD OF Integer AN 2
IF U SAY SO
HOW IZ I EthiopianProdukt YR a AN YR b
I HAS A Result ITZ 0
IM IN Y... |
http://rosettacode.org/wiki/Euler%27s_sum_of_powers_conjecture | Euler's sum of powers conjecture | There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin.
Euler's (disproved) sum of powers conjecture
At least k positive kth powers are required to sum to a kth power,
except for the trivial case... | #Tcl | Tcl | proc doit {{badx 250} {complete 0}} {
## NB: $badx is exclusive upper limit, and also limits y!
for {set y 1} {$y < $badx} {incr y} {
set s [expr {$y ** 5}]
set r5($s) $y ;# fifth roots of valid sums
}
for {set a 1} {$a < $badx} {incr a} {
set suma [expr {$a ** 5}]
... |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #Rascal | Rascal | public int factorial_iter(int n){
result = 1;
for(i <- [1..n])
result *= i;
return result;
} |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #min | min | 3 even?
4 even?
5 odd?
get-stack print |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #MiniScript | MiniScript | for i in range(-4, 4)
if i % 2 == 0 then print i + " is even" else print i + " is odd"
end for |
http://rosettacode.org/wiki/Emirp_primes | Emirp primes | An emirp (prime spelled backwards) are primes that when reversed (in their decimal representation) are a different prime.
(This rules out palindromic primes.)
Task
show the first twenty emirps
show all emirps between 7,700 and 8,000
show the 10,000th emirp
In each list, the numbe... | #Swift | Swift | import Foundation
extension BinaryInteger {
var isPrime: Bool {
if self == 0 || self == 1 {
return false
} else if self == 2 {
return true
}
let max = Self(ceil((Double(self).squareRoot())))
for i in stride(from: 2, through: max, by: 1) where self % i == 0 {
return false
... |
http://rosettacode.org/wiki/Emirp_primes | Emirp primes | An emirp (prime spelled backwards) are primes that when reversed (in their decimal representation) are a different prime.
(This rules out palindromic primes.)
Task
show the first twenty emirps
show all emirps between 7,700 and 8,000
show the 10,000th emirp
In each list, the numbe... | #Tcl | Tcl | package require math::numtheory
# Import only to keep line lengths down
namespace import math::numtheory::isprime
proc emirp? {n} {
set r [string reverse $n]
expr {$n != $r && [isprime $n] && [isprime $r]}
}
# Generate the various emirps
for {set n 2;set emirps {}} {[llength $emirps] < 20} {incr n} {
if... |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #Mercury | Mercury | S = "", % assignment
( if S = "" then ... else ... ), % checking if a string is empty
( if not S = "" then ... else ... ), % checking if a string is not empty |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #min | min | (bool not) :empty?
"" empty? puts!
"Rosetta Code" empty? puts! |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Julia | Julia | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #K | K | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #KonsolScript | KonsolScript | function main() {
} |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #REXX | REXX | /* REXX ***************************************************************
* 28.02.2013 Walter Pachl
* 12.03.2013 Walter Pachl typo in log corrected. thanx for testing
* 22.05.2013 -"- extended the logic to accept other strings
* 25.05.2013 -"- 'my' log routine is apparently incorrect
* 25.05.2013 -"- problem identified ... |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #Lua | Lua | function halve(a)
return a/2
end
function double(a)
return a*2
end
function isEven(a)
return a%2 == 0
end
function ethiopian(x, y)
local result = 0
while (x >= 1) do
if not isEven(x) then
result = result + y
end
x = math.floor(halve(x))
y = doubl... |
http://rosettacode.org/wiki/Euler%27s_sum_of_powers_conjecture | Euler's sum of powers conjecture | There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin.
Euler's (disproved) sum of powers conjecture
At least k positive kth powers are required to sum to a kth power,
except for the trivial case... | #UNIX_Shell | UNIX Shell | MAX=250
pow5=()
for (( i=1; i<MAX; ++i )); do
pow5[i]=$(( i*i*i*i*i ))
done
for (( a=1; a<MAX; ++a )); do
for (( b=a+1; b<MAX; ++b )); do
for (( c=b+1; c<MAX; ++c )); do
for (( d=c+1; d<MAX; ++d )); do
(( sum=pow5[a]+pow5[b]+pow5[c]+pow5[d] ))
(( low=d+3 ))
(( high=MAX ))
w... |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #RASEL | RASEL | 1&$:?v:1-3\$/1\
>$11\/.@ |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #MIPS_Assembly | MIPS Assembly |
.data
even_str: .asciiz "Even"
odd_str: .asciiz "Odd"
.text
#set syscall to get integer from user
li $v0,5
syscall
#perform bitwise AND and store in $a0
and $a0,$v0,1
#set syscall to print dytomh
li $v0,4
#jump to odd if the result of the AND operation
beq $a0,1,odd
even:
#load even_str message, ... |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #.D0.9C.D0.9A-61.2F52 | МК-61/52 | / 2 {x} ЗН |
http://rosettacode.org/wiki/Emirp_primes | Emirp primes | An emirp (prime spelled backwards) are primes that when reversed (in their decimal representation) are a different prime.
(This rules out palindromic primes.)
Task
show the first twenty emirps
show all emirps between 7,700 and 8,000
show the 10,000th emirp
In each list, the numbe... | #VBA | VBA | Option Explicit
Private Const MAX As Long = 5000000
Private Emirps As New Collection
Private CollTemp As New Collection
Sub Main()
Dim t
t = Timer
FillCollectionOfEmirps
Debug.Print "At this point : Execution time = " & Timer - t & " seconds."
Debug.Print "We have a Collection of the " & Emirps.Count & ... |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #Mirah | Mirah | empty_string1 = ""
empty_string2 = String.new
puts "empty string is empty" if empty_string1.isEmpty()
puts "empty string has no length" if empty_string2.length() == 0
puts "empty string is not nil" unless empty_string1 == nil |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #Nanoquery | Nanoquery | s = ""
if len(s)=0
println "s is empty"
else
println "s is not empty"
end |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Kotlin | Kotlin | fun main(a: Array<String>) {} |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Lambdatalk | Lambdatalk | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Lang5 | Lang5 | exit |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #Ring | Ring |
decimals(8)
entropy = 0
countOfChar = list(255)
source="1223334444"
charCount =len( source)
usedChar =""
for i =1 to len( source)
ch =substr(source, i, 1)
if not(substr( usedChar, ch)) usedChar =usedChar +ch ok
j =substr( usedChar, ch)
countOfChar[j] =countOfChar[j] +1
next
l =len(used... |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #Ruby | Ruby | def entropy(s)
counts = Hash.new(0.0)
s.each_char { |c| counts[c] += 1 }
leng = s.length
counts.values.reduce(0) do |entropy, count|
freq = count / leng
entropy - freq * Math.log2(freq)
end
end
p entropy("1223334444") |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #M2000_Interpreter | M2000 Interpreter |
Module EthiopianMultiplication{
Form 60, 25
Const Center=2, ColumnWith=12
Report Center,"Ethiopian Method of Multiplication"
// using decimals as unsigned integers
Def Decimal leftval, rightval, sum
(leftval, rightval)=(random(1, 65535), random(1, 65536))
Print $( , ColumnWith), "Target:", leftval*rightval,
H... |
http://rosettacode.org/wiki/Euler%27s_sum_of_powers_conjecture | Euler's sum of powers conjecture | There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin.
Euler's (disproved) sum of powers conjecture
At least k positive kth powers are required to sum to a kth power,
except for the trivial case... | #VBA | VBA | Public Declare Function GetTickCount Lib "kernel32.dll" () As Long
Public Sub begin()
start_int = GetTickCount()
main
Debug.Print (GetTickCount() - start_int) / 1000 & " seconds"
End Sub
Private Function pow(x, y) As Variant
pow = CDec(Application.WorksheetFunction.Power(x, y))
End Function
Private Sub ... |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #REBOL | REBOL | rebol [
Title: "Factorial"
URL: http://rosettacode.org/wiki/Factorial_function
]
; Standard recursive implementation.
factorial: func [n][
either n > 1 [n * factorial n - 1] [1]
]
; Iteration.
ifactorial: func [n][
f: 1
for i 2 n 1 [f: f * i]
f
]
; Automatic memoization.
; I'm just going to say up... |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #ML | ML |
fun even( x: int ) = (x mod 2 = 0);
fun odd( x: int ) = (x mod 2 = 1);
|
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #Modula-2 | Modula-2 | MODULE EvenOrOdd;
FROM FormatString IMPORT FormatString;
FROM Terminal IMPORT WriteString,ReadChar;
VAR
buf : ARRAY[0..63] OF CHAR;
i : INTEGER;
BEGIN
FOR i:=-5 TO 5 DO
FormatString("%i is even: %b\n", buf, i, i MOD 2 = 0);
WriteString(buf)
END;
ReadChar
END EvenOrOdd. |
http://rosettacode.org/wiki/Emirp_primes | Emirp primes | An emirp (prime spelled backwards) are primes that when reversed (in their decimal representation) are a different prime.
(This rules out palindromic primes.)
Task
show the first twenty emirps
show all emirps between 7,700 and 8,000
show the 10,000th emirp
In each list, the numbe... | #Visual_Basic_.NET | Visual Basic .NET | Imports System.Runtime.CompilerServices
Module Module1
<Extension()>
Function ToHashSet(Of T)(source As IEnumerable(Of T)) As HashSet(Of T)
Return New HashSet(Of T)(source)
End Function
<Extension()>
Function Reverse(number As Integer) As Integer
If number < 0 Then
Re... |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #Nemerle | Nemerle | def empty = "";
mutable fill_later = ""; |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #NESL | NESL | my_empty_string = "";
% To make sure it is empty, we can ask whether its length is equal to zero. %
#my_empty_string == 0; |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Lasso | Lasso | [] |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #LaTeX | LaTeX | \documentclass{minimal}
\begin{document}
\end{document} |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #Run_BASIC | Run BASIC | dim chrCnt( 255) ' possible ASCII chars
source$ = "1223334444"
numChar = len(source$)
for i = 1 to len(source$) ' count which chars are used in source
ch$ = mid$(source$,i,1)
if not( instr(chrUsed$, ch$)) then chrUsed$ = chrUsed$ + ch$
j = instr(chrUsed$, ch$)
chrCnt(j) =chrCnt(j) +1
next i
lc = len(... |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #Rust | Rust | fn entropy(s: &[u8]) -> f32 {
let mut histogram = [0u64; 256];
for &b in s {
histogram[b as usize] += 1;
}
histogram
.iter()
.cloned()
.filter(|&h| h != 0)
.map(|h| h as f32 / s.len() as f32)
.map(|ratio| -ratio * ratio.log2())
.sum()
}
fn ma... |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | IntegerHalving[x_]:=Floor[x/2]
IntegerDoubling[x_]:=x*2;
OddInteger OddQ
Ethiopian[x_, y_] :=
Total[Select[NestWhileList[{IntegerHalving[#[[1]]],IntegerDoubling[#[[2]]]}&, {x,y}, (#[[1]]>1&)], OddQ[#[[1]]]&]][[2]]
Ethiopian[17, 34] |
http://rosettacode.org/wiki/Euler%27s_sum_of_powers_conjecture | Euler's sum of powers conjecture | There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin.
Euler's (disproved) sum of powers conjecture
At least k positive kth powers are required to sum to a kth power,
except for the trivial case... | #VBScript | VBScript | Max=250
For X0=1 To Max
For X1=1 To X0
For X2=1 To X1
For X3=1 To X2
Sum=fnP5(X0)+fnP5(X1)+fnP5(X2)+fnP5(X3)
S1=Int(Sum^0.2)
If Sum=fnP5(S1) Then
WScript.StdOut.Write X0 & " " & X1 & " " & X2 & " " & X3 & " " & S1
WScript.Quit
End If
Next
Next
Next
Next
Function fnP5(n)
fnP5 =... |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #Red | Red | fac: function [n][r: 1 repeat i n [r: r * i] r]
fac: function [n][repeat i also n n: 1 [n: n * i] n] |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #Nanoquery | Nanoquery | def isEven(n)
if ((n % 2) = 1)
return false
else
return true
end
end
for i in range(1, 10)
print i
if isEven(i)
println " is even."
else
println " is odd."
end
end |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #Neko | Neko | var number = 6;
if(number % 2 == 0) {
$print("Even");
} else {
$print("Odd");
} |
http://rosettacode.org/wiki/Emirp_primes | Emirp primes | An emirp (prime spelled backwards) are primes that when reversed (in their decimal representation) are a different prime.
(This rules out palindromic primes.)
Task
show the first twenty emirps
show all emirps between 7,700 and 8,000
show the 10,000th emirp
In each list, the numbe... | #Wren | Wren | import "/math" for Int
var isEmirp = Fn.new{ |n|
if (!Int.isPrime(n)) return false
var ns = "%(n)"
var rs = ns[-1..0]
var r = Num.fromString(rs)
if (r == n) return false
if (Int.isPrime(r)) return true
return false
}
System.print("The first 20 emirps are:")
var count = 0
var i = 3
while ... |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols binary
s1 = '' -- assignment
s2 = "" -- equivalent to s1
parse '.' . s3 . -- parsing a token that doesn't exist results in an empty string
strings = [s1, s2, s3, ' ']
loop s_ = 0 to strings.length - 1
say (Rexx s_).right(3)':\-'
select
w... |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #LC3_Assembly | LC3 Assembly | .END |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Liberty_BASIC | Liberty BASIC | end |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #Scala | Scala | import scala.math._
def entropy( v:String ) = { v
.groupBy (a => a)
.values
.map( i => i.length.toDouble / v.length )
.map( p => -p * log10(p) / log10(2))
.sum
}
// Confirm that "1223334444" has an entropy of about 1.84644
assert( math.round( entropy("1223334444") * 100000 ) * 0.00001 == 1.84644 ) |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #scheme | scheme |
(define (entropy input)
(define (close? a b)
(define (norm x y)
(define (infinite_norm m n)
(define (absminus p q)
(cond ((null? p) '())
(else (cons (abs (- (car p) (car q))) (absminus (cdr p) (cdr q))))))
(define (mm l)
(cond ((null? (cdr l)) (ca... |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #MATLAB | MATLAB | function result = halveInt(number)
result = idivide(number,2,'floor');
end |
http://rosettacode.org/wiki/Euler%27s_sum_of_powers_conjecture | Euler's sum of powers conjecture | There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin.
Euler's (disproved) sum of powers conjecture
At least k positive kth powers are required to sum to a kth power,
except for the trivial case... | #Visual_Basic_.NET | Visual Basic .NET | Module Module1
Structure Pair
Dim a, b As Integer
Sub New(x as integer, y as integer)
a = x : b = y
End Sub
End Structure
Dim max As Integer = 250
Dim p5() As Long,
sum2 As SortedDictionary(Of Long, Pair) = New SortedDictionary(Of Long, Pair)
Functio... |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #Relation | Relation |
function factorial (n)
set result = 1
if n > 1
set k = 2
while k <= n
set result = result * k
set k = k + 1
end while
end if
end function
|
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #NESL | NESL | function even(n) = mod(n, 2) == 0;
% test the function by applying it to the first ten positive integers: %
{even(n) : n in [1:11]}; |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols nobinary
say 'Val'.right(5)': mod - ver - pos - bits'
say '---'.right(5)': ---- + ---- + ---- + ----'
loop nn = -15 to 15 by 3
say nn.right(5)':' eo(isEven(nn)) '-' eo(isEven(nn, 'v')) '-' eo(isEven(nn, 'p')) '-' eo(isEven(nn, 'b'))
end nn
ret... |
http://rosettacode.org/wiki/Emirp_primes | Emirp primes | An emirp (prime spelled backwards) are primes that when reversed (in their decimal representation) are a different prime.
(This rules out palindromic primes.)
Task
show the first twenty emirps
show all emirps between 7,700 and 8,000
show the 10,000th emirp
In each list, the numbe... | #zkl | zkl | var PS=Import("Src/ZenKinetic/sieve").postponed_sieve;
var ps=Utils.Generator(PS), plist=ps.walk(10).copy();
fcn isEmirp(p){ rp:=p.toString().reverse().toInt();
if(p==rp) return(False);
if(plist.holds(rp)) return(True);
tp:=p; mp:=p.max(rp); while(tp<mp) { plist.append(tp=ps.next()) }
return(tp==rp);
}
... |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #Nim | Nim | var x = ""
if x == "":
echo "empty"
if x != "":
echo "not empty"
# Alternatively:
if x.len == 0:
echo "empty"
if x.len > 0:
echo "not empty" |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #NS-HUBASIC | NS-HUBASIC | 10 S$=""
20 IF S$<>"" THEN O$="NOT "
30 PRINT "THE STRING IS "O$"EMPTY." |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Lilypond | Lilypond | \version "2.6.12" |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Lingo | Lingo | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Lisp | Lisp | |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #Scilab | Scilab | function E = entropy(d)
d=strsplit(d);
n=unique(string(d));
N=size(d,'r');
count=zeros(n);
n_size = size(n,'r');
for i = 1:n_size
count(i) = sum ( d == n(i) );
end
E=0;
for i=1:length(count)
E = E - count(i)/N * log(count(i)/N) / log(2);
end
endfunction
word ... |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #Seed7 | Seed7 | $ include "seed7_05.s7i";
include "float.s7i";
include "math.s7i";
const func float: entropy (in string: stri) is func
result
var float: entropy is 0.0;
local
var hash [char] integer: count is (hash [char] integer).value;
var char: ch is ' ';
var float: p is 0.0;
begin
for ch range stri ... |
Subsets and Splits
Rosetta Code COBOL Python Hard Tasks
Identifies and retrieves challenging tasks that exist in both COBOL and Python, revealing cross-language programming patterns and difficulty levels for comparative analysis.
Rosetta Code Task Comparisons
Identifies tasks common to both COBOL and Python languages that are described as having difficulty levels, revealing cross-language task similarities and providing useful comparative programming examples.
SQL Code Examples from Training Data
Retrieves raw SQL code examples for the SQL language, which is basic data retrieval without meaningful analysis or patterns.
SQL Code Examples from Training Data
Retrieves raw SQL code examples for the SQL language, which is basic filtering that shows what data looks like but doesn't provide meaningful analysis or patterns.
Select Specific Languages Codes
Retrieves specific programming language names and codes from training data, providing basic filtering but limited analytical value beyond identifying these particular languages.