root / trunk / web / dojo / dojox / math / _base.js @ 11
History | View | Annotate | Download (2.24 KB)
| 1 |
/*
|
|---|---|
| 2 |
Copyright (c) 2004-2010, The Dojo Foundation All Rights Reserved.
|
| 3 |
Available via Academic Free License >= 2.1 OR the modified BSD license.
|
| 4 |
see: http://dojotoolkit.org/license for details
|
| 5 |
*/
|
| 6 |
|
| 7 |
|
| 8 |
if(!dojo._hasResource["dojox.math._base"]){ |
| 9 |
dojo._hasResource["dojox.math._base"]=true; |
| 10 |
dojo.provide("dojox.math._base");
|
| 11 |
(function(){
|
| 12 |
var m=dojox.math;
|
| 13 |
dojo.mixin(dojox.math,{toRadians:function(n){
|
| 14 |
return (n*Math.PI)/180; |
| 15 |
},toDegrees:function(n){ |
| 16 |
return (n*180)/Math.PI; |
| 17 |
},degreesToRadians:function(n){ |
| 18 |
return m.toRadians(n);
|
| 19 |
},radiansToDegrees:function(n){ |
| 20 |
return m.toDegrees(n);
|
| 21 |
},_gamma:function(z){ |
| 22 |
var _1=1; |
| 23 |
while(--z>=1){ |
| 24 |
_1*=z; |
| 25 |
} |
| 26 |
if(z==0){ |
| 27 |
return _1;
|
| 28 |
} |
| 29 |
if(Math.floor(z)==z){
|
| 30 |
return NaN; |
| 31 |
} |
| 32 |
if(z==-0.5){ |
| 33 |
return Math.sqrt(Math.PI);
|
| 34 |
} |
| 35 |
if(z<-0.5){ |
| 36 |
return Math.PI/(Math.sin(Math.PI*(z+1))*this._gamma(-z)); |
| 37 |
} |
| 38 |
var a=13; |
| 39 |
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]; |
| 40 |
var _2=c[0]; |
| 41 |
for(var k=1;k<a;k++){ |
| 42 |
_2+=c[k]/(z+k); |
| 43 |
} |
| 44 |
return _1*Math.pow(z+a,z+0.5)/Math.exp(z)*_2; |
| 45 |
},factorial:function(n){ |
| 46 |
return this._gamma(n+1); |
| 47 |
},permutations:function(n,k){ |
| 48 |
if(n==0||k==0){ |
| 49 |
return 1; |
| 50 |
} |
| 51 |
return this.factorial(n)/this.factorial(n-k); |
| 52 |
},combinations:function(n,r){ |
| 53 |
if(n==0||r==0){ |
| 54 |
return 1; |
| 55 |
} |
| 56 |
return this.factorial(n)/(this.factorial(n-r)*this.factorial(r)); |
| 57 |
},bernstein:function(t,n,i){ |
| 58 |
return this.combinations(n,i)*Math.pow(t,i)*Math.pow(1-t,n-i); |
| 59 |
},gaussian:function(){ |
| 60 |
var k=2; |
| 61 |
do{
|
| 62 |
var i=2*Math.random()-1; |
| 63 |
var j=2*Math.random()-1; |
| 64 |
k=i*i+j*j; |
| 65 |
}while(k>=1); |
| 66 |
return i*Math.sqrt((-2*Math.log(k))/k); |
| 67 |
},range:function(a,b,_3){ |
| 68 |
if(arguments.length<2){ |
| 69 |
b=a,a=0;
|
| 70 |
} |
| 71 |
var _4=[],s=_3||1,i; |
| 72 |
if(s>0){ |
| 73 |
for(i=a;i<b;i+=s){
|
| 74 |
_4.push(i); |
| 75 |
} |
| 76 |
}else{
|
| 77 |
if(s<0){ |
| 78 |
for(i=a;i>b;i+=s){
|
| 79 |
_4.push(i); |
| 80 |
} |
| 81 |
}else{
|
| 82 |
throw new Error("dojox.math.range: step must not be zero."); |
| 83 |
} |
| 84 |
} |
| 85 |
return _4;
|
| 86 |
},distance:function(a,b){ |
| 87 |
return Math.sqrt(Math.pow(b[0]-a[0],2)+Math.pow(b[1]-a[1],2)); |
| 88 |
},midpoint:function(a,b){ |
| 89 |
if(a.length!=b.length){
|
| 90 |
console.error("dojox.math.midpoint: Points A and B are not the same dimensionally.",a,b);
|
| 91 |
} |
| 92 |
var m=[];
|
| 93 |
for(var i=0;i<a.length;i++){ |
| 94 |
m[i]=(a[i]+b[i])/2;
|
| 95 |
} |
| 96 |
return m;
|
| 97 |
}}); |
| 98 |
})(); |
| 99 |
} |