root / trunk / web / dojo / dojox / math / random / prng4.js @ 9
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/*
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Copyright (c) 2004-2010, The Dojo Foundation All Rights Reserved.
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Available via Academic Free License >= 2.1 OR the modified BSD license.
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see: http://dojotoolkit.org/license for details
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*/
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if(!dojo._hasResource["dojox.math.random.prng4"]){ |
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dojo._hasResource["dojox.math.random.prng4"]=true; |
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dojo.provide("dojox.math.random.prng4");
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(function(){
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function _1(){ |
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this.i=0; |
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this.j=0; |
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this.S=new Array(256); |
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}; |
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dojo.extend(_1,{init:function(_2){ |
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var i,j,t,S=this.S,_3=_2.length; |
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for(i=0;i<256;++i){ |
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S[i]=i; |
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} |
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j=0;
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for(i=0;i<256;++i){ |
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j=(j+S[i]+_2[i%_3])&255;
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t=S[i]; |
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S[i]=S[j]; |
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S[j]=t; |
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} |
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this.i=0; |
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this.j=0; |
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},next:function(){ |
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var t,i,j,S=this.S; |
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this.i=i=(this.i+1)&255; |
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this.j=j=(this.j+S[i])&255; |
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t=S[i]; |
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S[i]=S[j]; |
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S[j]=t; |
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return S[(t+S[i])&255]; |
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}}); |
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dojox.math.random.prng4=function(){ |
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return new _1(); |
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}; |
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dojox.math.random.prng4.size=256;
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})(); |
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} |