Subversion Repositories Applications.papyrus

/*
        Copyright (c) 2004-2006, The Dojo Foundation
        All Rights Reserved.

        Licensed under the Academic Free License version 2.1 or above OR the
        modified BSD license. For more information on Dojo licensing, see:

                http://dojotoolkit.org/community/licensing.shtml
*/



dojo.provide("dojo.math");
dojo.math.degToRad = function (x) {
        return (x * Math.PI) / 180;
};
dojo.math.radToDeg = function (x) {
        return (x * 180) / Math.PI;
};
dojo.math.factorial = function (n) {
        if (n < 1) {
                return 0;
        }
        var retVal = 1;
        for (var i = 1; i <= n; i++) {
                retVal *= i;
        }
        return retVal;
};
dojo.math.permutations = function (n, k) {
        if (n == 0 || k == 0) {
                return 1;
        }
        return (dojo.math.factorial(n) / dojo.math.factorial(n - k));
};
dojo.math.combinations = function (n, r) {
        if (n == 0 || r == 0) {
                return 1;
        }
        return (dojo.math.factorial(n) / (dojo.math.factorial(n - r) * dojo.math.factorial(r)));
};
dojo.math.bernstein = function (t, n, i) {
        return (dojo.math.combinations(n, i) * Math.pow(t, i) * Math.pow(1 - t, n - i));
};
dojo.math.gaussianRandom = function () {
        var k = 2;
        do {
                var i = 2 * Math.random() - 1;
                var j = 2 * Math.random() - 1;
                k = i * i + j * j;
        } while (k >= 1);
        k = Math.sqrt((-2 * Math.log(k)) / k);
        return i * k;
};
dojo.math.mean = function () {
        var array = dojo.lang.isArray(arguments[0]) ? arguments[0] : arguments;
        var mean = 0;
        for (var i = 0; i < array.length; i++) {
                mean += array[i];
        }
        return mean / array.length;
};
dojo.math.round = function (number, places) {
        if (!places) {
                var shift = 1;
        } else {
                var shift = Math.pow(10, places);
        }
        return Math.round(number * shift) / shift;
};
dojo.math.sd = dojo.math.standardDeviation = function () {
        var array = dojo.lang.isArray(arguments[0]) ? arguments[0] : arguments;
        return Math.sqrt(dojo.math.variance(array));
};
dojo.math.variance = function () {
        var array = dojo.lang.isArray(arguments[0]) ? arguments[0] : arguments;
        var mean = 0, squares = 0;
        for (var i = 0; i < array.length; i++) {
                mean += array[i];
                squares += Math.pow(array[i], 2);
        }
        return (squares / array.length) - Math.pow(mean / array.length, 2);
};
dojo.math.range = function (a, b, step) {
        if (arguments.length < 2) {
                b = a;
                a = 0;
        }
        if (arguments.length < 3) {
                step = 1;
        }
        var range = [];
        if (step > 0) {
                for (var i = a; i < b; i += step) {
                        range.push(i);
                }
        } else {
                if (step < 0) {
                        for (var i = a; i > b; i += step) {
                                range.push(i);
                        }
                } else {
                        throw new Error("dojo.math.range: step must be non-zero");
                }
        }
        return range;
};