Here is a function to make a shuffled copy of an array, written with only 92 bytes.
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140byt.es -- shuffleArray (92B)
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| function( | |
| a, // the given array | |
| b, // copy of a (placeholder) | |
| i, // index (placeholder) | |
| t // temporary variable (placeholder) | |
| ){ | |
| for(i in b=a.slice()) // for each i in [0, b.length[ | |
| // a is reused as an index | |
| a=0|i*m.random(), // Math.floor random( [0, i[ ) | |
| t=b[a],b[a]=b[i],b[i]=t; // swap b[a] and b[i] | |
| return b // return shuffled array | |
| } |
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| function(a,b,i,t){for(i in b=a.slice())a=0|i*Math.random(),t=b[a],b[a]=b[i],b[i]=t;return b} |
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| DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE | |
| Version 2, December 2004 | |
| Copyright © 2011 Baptiste Fontaine bfontaine.net | |
| Everyone is permitted to copy and distribute verbatim or modified | |
| copies of this license document, and changing it is allowed as long | |
| as the name is changed. | |
| DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE | |
| TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION | |
| 0. You just DO WHAT THE FUCK YOU WANT TO. |
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| { | |
| "name": "shuffleArray", | |
| "description": "return a shuffled version of an array using Fisher‑Yates algorithm.", | |
| "keywords": [ | |
| "array", | |
| "shuffle", | |
| "random", | |
| ] | |
| } |
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| <!DOCTYPE html> | |
| <title>shuffleArray</title> | |
| <div>Expected value: <b>a list of shuffled numbers from 1 to 10</b>.</div> | |
| <div>Actual value: <b id="ret"></b></div> | |
| <script> | |
| var myFunction = function(a,b,i,t){for(i in b=a.slice())a=0|i*Math.random(),t=b[a],b[a]=b[i],b[i]=t;return b} | |
| document.getElementById( "ret" ).innerHTML = myFunction([1,2,3,4,5,6,7,8,9,10]); | |
| </script> |
Thanks, in my first version I was using Math twice, so I created m and forgot to remove it.
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You don't need
msince you are usingMathonly once. And you can writefor(i in b=a.slice()). Also check this in-place shuffle using Fisher–Yates.