nanstdevtk.js (1418B)
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 nanvariancetk = require( './../../../base/nanvariancetk' ); 24 var sqrt = require( '@stdlib/math/base/special/sqrt' ); 25 26 27 // MAIN // 28 29 /** 30 * Computes the standard deviation of a strided array ignoring `NaN` values and using a one-pass textbook algorithm. 31 * 32 * @param {PositiveInteger} N - number of indexed elements 33 * @param {number} correction - degrees of freedom adjustment 34 * @param {NumericArray} x - input array 35 * @param {integer} stride - stride length 36 * @returns {number} standard deviation 37 * 38 * @example 39 * var x = [ 1.0, -2.0, NaN, 2.0 ]; 40 * 41 * var v = nanstdevtk( x.length, 1, x, 1 ); 42 * // returns ~2.0817 43 */ 44 function nanstdevtk( N, correction, x, stride ) { 45 return sqrt( nanvariancetk( N, correction, x, stride ) ); 46 } 47 48 49 // EXPORTS // 50 51 module.exports = nanstdevtk;