root / trunk / web / dojo / dojox / math / _base.js @ 10
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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._base"]){ |
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dojo._hasResource["dojox.math._base"]=true; |
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dojo.provide("dojox.math._base");
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(function(){
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var m=dojox.math;
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dojo.mixin(dojox.math,{toRadians:function(n){
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return (n*Math.PI)/180; |
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},toDegrees:function(n){ |
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return (n*180)/Math.PI; |
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},degreesToRadians:function(n){ |
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return m.toRadians(n);
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},radiansToDegrees:function(n){ |
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return m.toDegrees(n);
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},_gamma:function(z){ |
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var _1=1; |
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while(--z>=1){ |
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_1*=z; |
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} |
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if(z==0){ |
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return _1;
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} |
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if(Math.floor(z)==z){
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return NaN; |
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} |
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if(z==-0.5){ |
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return Math.sqrt(Math.PI);
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} |
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if(z<-0.5){ |
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return Math.PI/(Math.sin(Math.PI*(z+1))*this._gamma(-z)); |
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} |
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var a=13; |
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var c=[0.000005665805601518633,1.274371766337968,-4.937419909315511,7.872026703248596,-6.676050374943609,3.252529844448517,-0.9185252144102627,0.14474022977730785,-0.011627561382389852,0.0004011798075706662,-0.0000042652458386405745,6.665191329033609e-9,-1.5392547381874824e-13]; |
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var _2=c[0]; |
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for(var k=1;k<a;k++){ |
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_2+=c[k]/(z+k); |
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} |
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return _1*Math.pow(z+a,z+0.5)/Math.exp(z)*_2; |
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},factorial:function(n){ |
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return this._gamma(n+1); |
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},permutations:function(n,k){ |
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if(n==0||k==0){ |
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return 1; |
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} |
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return this.factorial(n)/this.factorial(n-k); |
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},combinations:function(n,r){ |
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if(n==0||r==0){ |
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return 1; |
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} |
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return this.factorial(n)/(this.factorial(n-r)*this.factorial(r)); |
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},bernstein:function(t,n,i){ |
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return this.combinations(n,i)*Math.pow(t,i)*Math.pow(1-t,n-i); |
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},gaussian:function(){ |
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var k=2; |
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do{
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var i=2*Math.random()-1; |
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var j=2*Math.random()-1; |
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k=i*i+j*j; |
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}while(k>=1); |
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return i*Math.sqrt((-2*Math.log(k))/k); |
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},range:function(a,b,_3){ |
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if(arguments.length<2){ |
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b=a,a=0;
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} |
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var _4=[],s=_3||1,i; |
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if(s>0){ |
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for(i=a;i<b;i+=s){
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_4.push(i); |
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} |
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}else{
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if(s<0){ |
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for(i=a;i>b;i+=s){
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_4.push(i); |
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} |
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}else{
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throw new Error("dojox.math.range: step must not be zero."); |
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} |
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} |
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return _4;
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},distance:function(a,b){ |
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return Math.sqrt(Math.pow(b[0]-a[0],2)+Math.pow(b[1]-a[1],2)); |
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},midpoint:function(a,b){ |
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if(a.length!=b.length){
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console.error("dojox.math.midpoint: Points A and B are not the same dimensionally.",a,b);
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} |
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var m=[];
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for(var i=0;i<a.length;i++){ |
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m[i]=(a[i]+b[i])/2;
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} |
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return m;
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}}); |
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})(); |
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} |