dstdevyc.js (1785B)
1 /** 2 * @license Apache-2.0 3 * 4 * Copyright (c) 2020 The Stdlib Authors. 5 * 6 * Licensed under the Apache License, Version 2.0 (the "License"); 7 * you may not use this file except in compliance with the License. 8 * You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 19 'use strict'; 20 21 // MODULES // 22 23 var dvarianceyc = require( './../../../base/dvarianceyc' ); 24 var sqrt = require( '@stdlib/math/base/special/sqrt' ); 25 26 27 // MAIN // 28 29 /** 30 * Computes the standard deviation of a double-precision floating-point strided array using a one-pass algorithm proposed by Youngs and Cramer. 31 * 32 * ## References 33 * 34 * - Youngs, Edward A., and Elliot M. Cramer. 1971. "Some Results Relevant to Choice of Sum and Sum-of-Product Algorithms." _Technometrics_ 13 (3): 657–65. doi:[10.1080/00401706.1971.10488826](https://doi.org/10.1080/00401706.1971.10488826). 35 * 36 * @param {PositiveInteger} N - number of indexed elements 37 * @param {number} correction - degrees of freedom adjustment 38 * @param {Float64Array} x - input array 39 * @param {integer} stride - stride length 40 * @returns {number} standard deviation 41 * 42 * @example 43 * var Float64Array = require( '@stdlib/array/float64' ); 44 * 45 * var x = new Float64Array( [ 1.0, -2.0, 2.0 ] ); 46 * var N = x.length; 47 * 48 * var v = dstdevyc( N, 1, x, 1 ); 49 * // returns ~2.0817 50 */ 51 function dstdevyc( N, correction, x, stride ) { 52 return sqrt( dvarianceyc( N, correction, x, stride ) ); 53 } 54 55 56 // EXPORTS // 57 58 module.exports = dstdevyc;