qminer
Version:
A C++ based data analytics platform for processing large-scale real-time streams containing structured and unstructured data
39 lines (34 loc) • 1.3 kB
JavaScript
/**
* Copyright (c) 2015, Jozef Stefan Institute, Quintelligence d.o.o. and contributors
* All rights reserved.
*
* This source code is licensed under the FreeBSD license found in the
* LICENSE file in the root directory of this source tree.
*/
module.exports = exports = function (pathQmBinary) {
var qm = require(pathQmBinary); // This loads only c++ functions of qm
exports = qm.statistics;
//!STARTJSDOC
/**
* Calculates the z-score for a point sampled from a Gaussian distribution. The z-score indicates
* how many standard deviations an element is from the meam and can be calculated using
* the following formula: `z = (x - mu) / sigma`.
* @param {Number} x - The sampled point.
* @param {Number} mu - Mean of the distribution.
* @param {Number} sigma - Variance of the distribution.
* @returns {number} The z-score of the sampled point.
* @example
* // import modules
* var stat = require('qminer').statistics;
* // calculate the z-score of the sampled point
* var point = 10;
* var mu = 5;
* var sigma = 5;
* var zScore = stat.getZScore(point, mu, sigma); // returns 1
*/
exports.getZScore = function (x, mu, sigma) {
return (x - mu) / sigma;
}
//!ENDJSDOC
return exports;
}