Entropy/Narcissist: Difference between revisions
→{{header|jq}}: def sum():
(→{{header|Wren}}: Now uses new core library method.) |
(→{{header|jq}}: def sum():) |
||
(12 intermediate revisions by 10 users not shown) | |||
Line 1:
{{task}}
[[File:ENTROPY.JPG|
;Task:
Line 12:
=={{header|Ada}}==
<
with Ada.Command_Line;
with Ada.Numerics.Elementary_Functions;
Line 77:
Float_Io.Put (Entr);
New_Line;
end Entropy;</
{{out}}
<pre>Entropy of 'entropy.adb' is 4.559854</pre>
Line 86:
Note that the source here uses spaces, not tabs, hence the low entropy, replacing all runs of four spaces with a single space
results in an entropy of +4.64524532762062e +0.
<
# calculate the shannon entropy of a string #
PROC shannon entropy = ( STRING s )REAL:
Line 144:
print( ( shannon entropy( file contents ), newline ) )
FI
END</
{{out}}
<pre>
Line 152:
=={{header|AutoHotkey}}==
{{works with|AutoHotkey 1.1}}
<
MsgBox, % Entropy(var)
Line 167:
}
return, e
}</
{{Output}}
<pre>5.942956</pre>
=={{header|AWK}}==
The record separator RS is set to end of file. So getline reads the whole file in one line.
<syntaxhighlight lang="awk">
BEGIN{FS=""
RS="\x04"#EOF
getline<"entropy.awk"
for(i=1;i<=NF;i++)H[$i]++
for(i in H)E-=(h=H[i]/NF)*log(h)
print "bytes ",NF," entropy ",E/log(2)
exit}</syntaxhighlight>
{{Output}}
<pre>bytes 158 entropy 5.2802</pre>
=={{header|BBC BASIC}}==
{{works with|BBC BASIC for Windows}}
<syntaxhighlight lang="bbcbasic"> DIM Freq%(255)
FOR I%=PAGE TO LOMEM Freq%(?I%)+=1 NEXT
Size=LOMEM - PAGE
FOR I%=0 TO 255
IF Freq%(I%) Entropy+=Freq%(I%) / Size * LN(Freq%(I%) / Size) / LN(2)
NEXT
PRINT "My size is ";Size " bytes and my entropy is ";-Entropy "!"
END</syntaxhighlight>
{{out}}
<pre>My size is 224 bytes and my entropy is 5.11257089!</pre>
=={{header|C}}==
Line 176 ⟶ 202:
Assumes that the source file is stored in the working directory as "entropy.c".
<
#include <stdlib.h>
#include <stdbool.h>
Line 223 ⟶ 249:
printf("%lf\n",H);
return 0;
}</
{{out}}
<syntaxhighlight lang="text">5.195143</
=={{header|C++}}==
<
#include <fstream>
#include <cmath>
Line 268 ⟶ 294:
cout<<entropy(readFile("entropy.cpp"));
return 0;
}</
{{out}}
<pre>4.58688</pre>
Line 274 ⟶ 300:
=={{header|Crystal}}==
{{trans|Ruby}}
<
counts = s.chars.each_with_object(Hash(Char, Float64).new(0.0)) { |c, h| h[c] += 1 }
counts.values.sum do |count|
Line 282 ⟶ 308:
end
puts entropy File.read(__FILE__)</
{{out}}
<pre>
Line 289 ⟶ 315:
=={{header|D}}==
<
import std.stdio, std.algorithm, std.math, std.file;
Line 299 ⟶ 325:
.sum
.writeln;
}</
{{out}}
<pre>6.29803</pre>
=={{header|Elixir}}==
<
text = IO.read(file, :all)
leng = String.length(text)
Line 315 ⟶ 341:
end)
|> IO.puts
end)</
{{out}}
Line 323 ⟶ 349:
=={{header|Emacs Lisp}}==
<
(let ((freq-table (make-hash-table))
(entropy 0)
Line 342 ⟶ 368:
(shannon-entropy (with-temp-buffer
(insert-file-contents "U:/rosetta/narcissist.el")
(buffer-string))))</
{{out}}
<
4.5129548515535785</
=={{header|Erlang}}==
<
-define(LOG2E, 1.44269504088896340735992).
Line 372 ⟶ 398:
_ -> count(Data, I+1, Frq #{Chr => 1})
end.
</syntaxhighlight>
{{out}}
<pre>
Line 379 ⟶ 405:
=={{header|Factor}}==
<
math.functions math.statistics prettyprint sequences ;
IN: rosetta-code.entropy-narcissist
Line 390 ⟶ 416:
"entropy-narcissist.factor" utf8 [
contents entropy .
] with-file-reader</
{{out}}
<pre>
Line 397 ⟶ 423:
=={{header|FreeBASIC}}==
<
' compile with: fbc -s console
' modified code from ENTROPY entry
Line 449 ⟶ 475:
Print : Print "hit any key to end program"
Sleep
End</
{{out}}
<pre>Windows version
Line 462 ⟶ 488:
=={{header|Go}}==
<
import (
Line 496 ⟶ 522:
l := float64(len(d))
return math.Log2(l) - hm/l
}</
{{out}}
<pre>
Line 504 ⟶ 530:
=={{header|Haskell}}==
<
import Data.List
import System.Environment
Line 514 ⟶ 540:
entropy = sort >>> group >>> map genericLength >>> normalize >>> map lg >>> sum
where lg c = -c * logBase 2 c
normalize c = let sc = sum c in map (/ sc) c</
{{out}} In a shell
Line 531 ⟶ 557:
=={{header|J}}==
'''Solution''':<
1!:2&2 entropy 1!:1 (4!:4 <'entropy') { 4!:3''</
'''Example''':<
4.73307</
=={{header|Java}}==
<
import java.io.BufferedReader;
import java.io.File;
Line 579 ⟶ 605:
}
</syntaxhighlight>
{{out}}
<pre>Entropy of file "src/EntropyNarcissist.java" = 4.691381977073.</pre>
=={{header|jq}}==
'''Works with jq, the C implementation of jq'''
'''Works with gojq, the Go implementation of jq'''
'''Works with jaq, the Rust implementation of jq'''
The program assumes it will be presented to itself using
an invocation of jq with the -sR options, along the lines of:
<pre>
jq -sR -f entropy-narcissist.jq < entropy-narcissist.jq
</pre>
If your jq supports `keys_unsorted`, feel free to use it instead of `keys`.
<syntaxhighlight lang="jq">
def chars: explode[] | [.] | implode;
def bow(stream):
reduce stream as $word ({}; .[($word|tostring)] += 1);
def sum(s): reduce s as $x (0; .+$x);
length as $l
| bow(chars)
| sum(keys[] as $k | .[$k] as $c | $c * ($c|log2) )
| ($l|log2) - ./$l
</syntaxhighlight>
{{output}}
<pre>
{{output}}
<pre>
4.796499915496963
</pre>
=={{header|Julia}}==
<
entropy(s) = -sum(x -> x / length(s) * log2(x / length(s)), values(counter(s)))
println("self-entropy: ", entropy(read(Base.source_path(), String)))</
{{out}}
Line 594 ⟶ 654:
=={{header|Kotlin}}==
<
fun log2(d: Double) = Math.log(d) / Math.log(2.0)
Line 616 ⟶ 676:
val prog = java.io.File("entropy_narc.kt").readText()
println("This program's entropy is ${"%18.16f".format(shannon(prog))}")
}</
{{out}}
Line 625 ⟶ 685:
=={{header|Lua}}==
arg[0] gives the path of the script currently being executed
<
local inFile = io.open(filename, "r")
local fileContent = inFile:read("*all")
Line 650 ⟶ 710:
end
print(entropy(getFile(arg[0])))</
{{out}}
<pre>4.3591214356783</pre>
Line 657 ⟶ 717:
As we have compiled without specific options to change the way the executable is named, we can retrieve the source file name by adding the suffix “.nim” to the executable file name. We suppose also that the source file is in the same directory as the executable (which is true in our environment).
<
let execName = getAppFilename().splitPath().tail
Line 670 ⟶ 730:
echo "Source file entropy: ", srcName.readFile().entropy().formatFloat(ffDecimal, 5)
echo "Binary file entropy: ", execName.readFile().entropy().formatFloat(ffDecimal, 5)</
{{out}}
Line 677 ⟶ 737:
=={{header|PARI/GP}}==
<
entropy(Str(entropy))</
{{out}}
<pre>%1 = 4.54978213</pre>
=={{header|Perl}}==
<
use strict ;
use warnings ;
Line 709 ⟶ 769:
}
$infocontent *= -1 ;
say "The information content of the source file is $infocontent !" ;</
{{out}}
<pre>The information content of the source file is 4.6487923749222 !</pre>
Line 715 ⟶ 775:
=={{header|Phix}}==
Minor edit to the [[Entropy#Phix|Entropy]] answer, if compiled assumes source code is in the same directory.
<!--<syntaxhighlight lang="phix">(notonline)-->
<span style="color: #008080;">without</span> <span style="color: #008080;">js</span> <span style="color: #000080;font-style:italic;">-- command_line, file i/o</span>
<span style="color: #008080;">function</span> <span style="color: #000000;">entropy</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">)</span>
<span style="color: #004080;">sequence</span> <span style="color: #000000;">symbols</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{},</span>
<span style="color: #000000;">counts</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
<span style="color: #004080;">integer</span> <span style="color: #000000;">N</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">s</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">N</span> <span style="color: #008080;">do</span>
<span style="color: #004080;">object</span> <span style="color: #000000;">si</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span>
<span style="color: #004080;">integer</span> <span style="color: #000000;">k</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">find</span><span style="color: #0000FF;">(</span><span style="color: #000000;">si</span><span style="color: #0000FF;">,</span><span style="color: #000000;">symbols</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">k</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
<span style="color: #000000;">symbols</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">symbols</span><span style="color: #0000FF;">,</span><span style="color: #000000;">si</span><span style="color: #0000FF;">)</span>
<span style="color: #000000;">counts</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">counts</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span>
<span
<span style="color: #000000;">counts</span><span style="color: #0000FF;">[</span><span style="color: #000000;">k</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #004080;">atom</span> <span style="color: #000000;">H</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">counts</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
<span style="color: #004080;">atom</span> <span style="color: #000000;">ci</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">counts</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]/</span><span style="color: #000000;">N</span>
<span style="color: #000000;">H</span> <span style="color: #0000FF;">-=</span> <span style="color: #000000;">ci</span><span style="color: #0000FF;">*</span><span style="color: #7060A8;">log2</span><span style="color: #0000FF;">(</span><span style="color: #000000;">ci</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #008080;">return</span> <span style="color: #000000;">H</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
<span style="color: #0000FF;">?</span><span style="color: #000000;">entropy</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">get_text</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">open</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">substitute</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">command_line</span><span style="color: #0000FF;">()[</span><span style="color: #000000;">2</span><span style="color: #0000FF;">],</span><span style="color: #008000;">".exe"</span><span style="color: #0000FF;">,</span><span style="color: #008000;">".exw"</span><span style="color: #0000FF;">)),</span><span style="color: #008000;">"rb"</span><span style="color: #0000FF;">))</span>
<!--</syntaxhighlight>-->
Output is eg 4.993666233, but that may vary with Windows/Linux line endings, tabs vs spaces, trailing returns, BOM headers, etc.
=={{header|PHP}}==
<
$h = 0;
$s = file_get_contents(__FILE__);
Line 758 ⟶ 813:
( $c / $l ) *
log( $c / $l, 2 );
echo $h;</
{{out}}
<pre>2.9339128173013</pre>
=={{header|Picat}}==
{{trans|Go}}
{{works with|Picat}}
<syntaxhighlight lang="picat">
entropy(File) = E =>
Bytes = read_file_bytes(File),
F = [0: I in 1..256],
foreach (B in Bytes)
B1 := B + 1,
F[B1] := F[B1] + 1
end,
HM = 0,
foreach (C in F)
if (C > 0) then
HM := HM + C * log(2, C)
end
end,
L = Bytes.length,
E = log(2, L) - HM / L.
main(Args) =>
printf("Entropy: %f\n", entropy(Args[1])).
</syntaxhighlight>
{{out}}
<pre>
$ picat entropy.pi entropy.pi
Entropy: 4.384622
</pre>
=={{header|PicoLisp}}==
<syntaxhighlight lang="picolisp">
(scl 8)
(load "@lib/math.l")
Line 795 ⟶ 879:
(bye)
</syntaxhighlight>
{{Out}}
<pre>
My entropy is 4.12169822
</pre>
=={{header|Python}}==
{{works with|Python 3.4}}
Line 805 ⟶ 890:
Minor edit to the [[Entropy#Python|Entropy]] answer.
<
from collections import Counter
Line 815 ⟶ 900:
b=f.read()
print(entropy(b))</
{{Output}}
<pre>4.575438063744619</pre>
Line 821 ⟶ 906:
=={{header|Racket}}==
The entropy of the program below is 4.512678555350348.
<
#lang racket
(require math)
Line 829 ⟶ 914:
(- (for/sum ([(d c) (in-hash (samples->hash ds))])
(* (/ c n) (log2 (/ c n)))))
</syntaxhighlight>
=={{header|Raku}}==
(formerly Perl 6)
{{Works with|rakudo|2016.05}}
<syntaxhighlight lang="raku"
given slurp($*PROGRAM-NAME).comb</
Result should be in the neighborhood of 4.9
{{out}}
Line 842 ⟶ 927:
=={{header|REXX}}==
REXX doesn't have a BIF (built-in function) for '''log''' or '''ln''', so the subroutine (function) '''log2''' is included herein.
<
numeric digits length( e() ) % 2 - length(.) /*use 1/2 of the decimal digits of E. */
#= 0; @.= 0; $=; $$=; recs= sourceline() /*define some handy─dandy REXX vars. */
Line 872 ⟶ 957:
ox=izz; ii=ii+is*2**j; end /*while*/; x= x * e** -ii -1; z= 0; _= -1; p= z
do k=1; _= -_ * x; z= z+_/k; if z=p then leave; p= z; end /*k*/
r= z + ii; if arg()==2 then return r; return r / log2(2,.)</
{{out|output|text= when using this REXX program as input:}}
<pre>
Line 883 ⟶ 968:
=={{header|Ruby}}==
<
counts = s.each_char.tally
size = s.size.to_f
Line 894 ⟶ 979:
s = File.read(__FILE__)
p entropy(s)
</syntaxhighlight>
{{out}}
<pre>4.653607496799478
Line 900 ⟶ 985:
=={{header|Rust}}==
<
use std::io::{Read, BufReader};
Line 925 ⟶ 1,010:
let file = BufReader::new(File::open(name).expect("Could not read file."));
println!("Entropy is {}.", entropy(file.bytes().flatten()));
}</
{{out}}
<pre>Entropy is 5.7108583.</pre>
=={{header|Sidef}}==
<
[0,
s.chars.freq.values.map {|c|
Line 939 ⟶ 1,024:
}
say entropy(File(__FILE__).open_r.slurp)</
{{out}}
<pre>
Line 947 ⟶ 1,032:
=={{header|Tcl}}==
Note that this code doesn't bother to close the open handle on the script; it is only suitable as a demonstration program.
<
set log2 [expr log(2)]
foreach char [split $str ""] {dict incr counts $char}
Line 958 ⟶ 1,043:
}
puts [format "entropy = %.5f" [entropy [read [open [info script]]]]]</
{{out}}
<pre>
entropy = 4.59099
</pre>
=={{header|V (Vlang)}}==
{{trans|Go}}
<syntaxhighlight lang="go">import os
import math
fn main() {
println("Binary file entropy: ${entropy(os.args[0])?}")
}
fn entropy(file string) ?f64 {
d := os.read_bytes(file)?
mut f := [256]f64{}
for b in d {
f[b]++
}
mut hm := 0.0
for c in f {
if c > 0 {
hm += c * math.log2(c)
}
}
l := f64(d.len)
return math.log2(l) - hm/l
}</syntaxhighlight>
{{out}}
<pre>
Binary file entropy: 5.676177202237735
</pre>
=={{header|Wren}}==
Basically an amalgam of the code in the [[Print_itself#Wren]] and [[Entropy#Wren]] tasks.
<
import "io" for File
Line 982 ⟶ 1,097:
}
var l = s.count
System.print(l.log2 - hm/l)</
{{out}}
Line 988 ⟶ 1,103:
4.6302314663
</pre>
=={{header|XPL0}}==
To run: entropy < entropy.xpl
<syntaxhighlight lang "XPL0">int Count(128), I, Len, Ch;
real Sum, Prob;
[for I:= 0 to 127 do Count(I):= 0;
Len:= 0;
loop [Ch:= ChIn(1);
if Ch = $1A\EOF\ then quit;
Count(Ch):= Count(Ch)+1;
Len:= Len+1;
];
Sum:= 0.;
for I:= 0 to 127 do
if Count(I) then
[Prob:= float(Count(I)) / float(Len);
Sum:= Sum + Prob*Ln(Prob);
];
RlOut(0, -Sum/Ln(2.));
]</syntaxhighlight>
{{out}}
<pre>
4.63457</pre>
=={{header|zkl}}==
Minor edit to the [[Entropy#zkl|Entropy]] answer.
<
text.pump(Void,fcn(c,freq){ c=c.toAsc(); freq[c]=freq[c]+1; freq }
.fp1((0).pump(256,List,(0.0).create.fp(0)).copy()))
Line 1,000 ⟶ 1,138:
}
entropy(File("entropy.zkl").read().text).println();</
{{out}}
<pre>
|