tsaniel/LICENSE.txt

## README.md

      
    Raw
  

              README.md
            
          
    Count the consecutive zero bits on the right of an binary number w/bitwise trick

Idea from http://graphics.stanford.edu/~seander/bithacks.html. One usage is to find the log base 2 of an integer, and it's faster than Math.log in some browsers.

  
## annotated.js
function(a){
    return
      ';<W=XIS>YQOJTL?CZVHRPNKBUGMAF@ED'// the lookup table
      .charCodeAt((a&-a)*125613361>>>27) - 59 // the unique index
}

## index.js
function(a){return';<W=XIS>YQOJTL?CZVHRPNKBUGMAF@ED'.charCodeAt((a&-a)*125613361>>>27)-59}

## LICENSE.txt
            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
                    Version 2, December 2004

 Copyright (C) 2011 YOUR_NAME_HERE <YOUR_URL_HERE>

 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.

## package.json
{
  "name": "countZeros",

  "description": "Count the consecutive zero bits on the right",

  "keywords": [
    "bitwise",
    "binary",
    "zeros"
  ]
}

## test.html
<!DOCTYPE html>
<title>log base 2</title>
<div>Expected value: <b>30</b></div>
<div>Actual value: <b id="ret"></b></div>
<script>
  // write a small example that shows off the API for your example
  // and tests it in one fell swoop.

  var myFunction = function(a){return';<W=XIS>YQOJTL?CZVHRPNKBUGMAF@ED'.charCodeAt((a&-a)*125613361>>>27)-59};

  document.getElementById( "ret" ).innerHTML = myFunction(1073741824);
</script>
	function(a){
	return
	';<W=XIS>YQOJTL?CZVHRPNKBUGMAF@ED'// the lookup table
	.charCodeAt((a&-a)*125613361>>>27) - 59 // the unique index
	}
	DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
	Version 2, December 2004

	Copyright (C) 2011 YOUR_NAME_HERE <YOUR_URL_HERE>

	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.
	{
	"name": "countZeros",

	"description": "Count the consecutive zero bits on the right",

	"keywords": [
	"bitwise",
	"binary",
	"zeros"
	]
	}
	<!DOCTYPE html>
	<title>log base 2</title>
	<div>Expected value: <b>30</b></div>
	<div>Actual value: <b id="ret"></b></div>
	<script>
	// write a small example that shows off the API for your example
	// and tests it in one fell swoop.

	var myFunction = function(a){return';<W=XIS>YQOJTL?CZVHRPNKBUGMAF@ED'.charCodeAt((a&-a)*125613361>>>27)-59};

	document.getElementById( "ret" ).innerHTML = myFunction(1073741824);
	</script>