Subversion Repositories Applications.papyrus

Rev

Rev 1318 | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
1318 alexandre_ 1 
/*
2 
	Copyright (c) 2004-2006, The Dojo Foundation
3 
	All Rights Reserved.
4 
 
5 
	Licensed under the Academic Free License version 2.1 or above OR the
6 
	modified BSD license. For more information on Dojo licensing, see:
7 
 
8 
		http://dojotoolkit.org/community/licensing.shtml
9 
*/
10 
 
1422 alexandre_ 11 
 
12 
 
1318 alexandre_ 13 
dojo.provide("dojo.math");
14 
dojo.math.degToRad = function (x) {
15 
	return (x * Math.PI) / 180;
16 
};
17 
dojo.math.radToDeg = function (x) {
18 
	return (x * 180) / Math.PI;
19 
};
20 
dojo.math.factorial = function (n) {
21 
	if (n < 1) {
22 
		return 0;
23 
	}
24 
	var retVal = 1;
25 
	for (var i = 1; i <= n; i++) {
26 
		retVal *= i;
27 
	}
28 
	return retVal;
29 
};
30 
dojo.math.permutations = function (n, k) {
31 
	if (n == 0 || k == 0) {
32 
		return 1;
33 
	}
34 
	return (dojo.math.factorial(n) / dojo.math.factorial(n - k));
35 
};
36 
dojo.math.combinations = function (n, r) {
37 
	if (n == 0 || r == 0) {
38 
		return 1;
39 
	}
40 
	return (dojo.math.factorial(n) / (dojo.math.factorial(n - r) * dojo.math.factorial(r)));
41 
};
42 
dojo.math.bernstein = function (t, n, i) {
43 
	return (dojo.math.combinations(n, i) * Math.pow(t, i) * Math.pow(1 - t, n - i));
44 
};
45 
dojo.math.gaussianRandom = function () {
46 
	var k = 2;
47 
	do {
48 
		var i = 2 * Math.random() - 1;
49 
		var j = 2 * Math.random() - 1;
50 
		k = i * i + j * j;
51 
	} while (k >= 1);
52 
	k = Math.sqrt((-2 * Math.log(k)) / k);
53 
	return i * k;
54 
};
55 
dojo.math.mean = function () {
56 
	var array = dojo.lang.isArray(arguments[0]) ? arguments[0] : arguments;
57 
	var mean = 0;
58 
	for (var i = 0; i < array.length; i++) {
59 
		mean += array[i];
60 
	}
61 
	return mean / array.length;
62 
};
63 
dojo.math.round = function (number, places) {
64 
	if (!places) {
65 
		var shift = 1;
66 
	} else {
67 
		var shift = Math.pow(10, places);
68 
	}
69 
	return Math.round(number * shift) / shift;
70 
};
71 
dojo.math.sd = dojo.math.standardDeviation = function () {
72 
	var array = dojo.lang.isArray(arguments[0]) ? arguments[0] : arguments;
73 
	return Math.sqrt(dojo.math.variance(array));
74 
};
75 
dojo.math.variance = function () {
76 
	var array = dojo.lang.isArray(arguments[0]) ? arguments[0] : arguments;
77 
	var mean = 0, squares = 0;
78 
	for (var i = 0; i < array.length; i++) {
79 
		mean += array[i];
80 
		squares += Math.pow(array[i], 2);
81 
	}
82 
	return (squares / array.length) - Math.pow(mean / array.length, 2);
83 
};
84 
dojo.math.range = function (a, b, step) {
85 
	if (arguments.length < 2) {
86 
		b = a;
87 
		a = 0;
88 
	}
89 
	if (arguments.length < 3) {
90 
		step = 1;
91 
	}
92 
	var range = [];
93 
	if (step > 0) {
94 
		for (var i = a; i < b; i += step) {
95 
			range.push(i);
96 
		}
97 
	} else {
98 
		if (step < 0) {
99 
			for (var i = a; i > b; i += step) {
100 
				range.push(i);
101 
			}
102 
		} else {
103 
			throw new Error("dojo.math.range: step must be non-zero");
104 
		}
105 
	}
106 
	return range;
107 
};
108