GZ/nwyj/WebContent/admin/scripts/dojo/dojox/math/_base.js

if (!dojo._hasResource["dojox.math._base"]) { // _hasResource checks added by
												// build. Do not use
												// _hasResource directly in your
												// code.
	dojo._hasResource["dojox.math._base"] = true;
	dojo.provide("dojox.math._base");

	dojo.mixin(dojox.math, {
		degreesToRadians : function(/* Number */n) {
			// summary
			// Convert the passed number to radians.
			return (n * Math.PI) / 180; // Number
		},
		radiansToDegrees : function(/* Number */n) {
			// summary
			// Convert the passed number to degrees.
			return (n * 180) / Math.PI; // Number
		},

		factoral : function(/* Number */n) {
			// summary
			// Return the factoral of n.
			if (n < 1) {
				return 0; // Number
			}
			var ret = 1;
			for (var i = 1; i <= n; i++) {
				ret *= i;
			}
			return ret; // Number
		},
		permutations : function(/* Number */n, /* Number */k) {
			// summary
			// TODO
			if (n == 0 || k == 0) {
				return 1; // Number
			}
			return (this.factoral(n) / this.factoral(n - k));
		},
		combinations : function(/* Number */n, /* Number */r) {
			// summary
			// TODO
			if (n == 0 || r == 0) {
				return 1; // Number
			}
			return (this.factoral(n) / (this.factoral(n - r) * this.factoral(r))); // Number
		},
		bernstein : function(/* Number */t, /* Number */n, /* Number */i) {
			// summary
			// TODO
			return (this.combinations(n, i) * Math.pow(t, i) * Math.pow(1 - t,
					n - i)); // Number
		},
		gaussian : function() {
			// summary
			// Return a random number based on the Gaussian algo.
			var k = 2;
			do {
				var i = 2 * Math.random() - 1;
				var j = 2 * Math.random() - 1;
				k = i * i + j * j;
			} while (k >= 1);
			return (i * Math.sqrt((-2 * Math.log(k)) / k)); // Number
		},

		// basic statistics
		sd : function(/* Array */a) {
			// summary
			// Returns the standard deviation of the passed arguments.
			return Math.sqrt(this.variance(a)); // Number
		},
		variance : function(/* Array */a) {
			// summary
			// Find the variance in the passed array of numbers.
			var mean = 0, squares = 0;
			dojo.forEach(a, function(item) {
						mean += item;
						squares += Math.pow(item, 2);
					});
			return (squares / a.length) - Math.pow(mean / a.length, 2); // Number
		},

		// create a range of numbers
		range : function(/* Number */a, /* Number? */b, /* Number? */step) {
			// summary
			// Create a range of numbers based on the parameters.
			if (arguments.length < 2) {
				b = a, a = 0;
			}
			var s = step || 1;
			var range = [];
			if (s > 0) {
				for (var i = a; i < b; i += s) {
					range.push(i);
				}
			} else {
				if (s < 0) {
					for (var i = a; i > b; i += s) {
						range.push(i);
					}
				} else {
					throw new Error("dojox.math.range: step must not be zero.");
				}
			}
			return range; // Array
		},
		distance : function(/* Array */a, /* Array */b) {
			// summary
			// Calculate the distance between point A and point B
			return Math.sqrt(Math.pow(b[0] - a[0], 2)
					+ Math.pow(b[1] - a[1], 2)); // Number
		},
		midpoint : function(/* Array */a, /* Array */b) {
			// summary
			// Calculate the midpoint between points A and B. A and B may be
			// multidimensional.
			if (a.length != b.length) {
				console
						.error(
								"dojox.math.midpoint: Points A and B are not the same dimensionally.",
								a, b);
			}
			var m = [];
			for (var i = 0; i < a.length; i++) {
				m[i] = (a[i] + b[i]) / 2;
			}
			return m; // Array
		}
	});

}