ndarray.js (1656B)
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 dnansumpw = require( './dnansumpw.js' ); 24 25 26 // VARIABLES // 27 28 var WORKSPACE = [ 0.0, 0 ]; 29 30 31 // MAIN // 32 33 /** 34 * Computes the arithmetic mean of a double-precision floating-point strided array, ignoring `NaN` values and using pairwise summation. 35 * 36 * @param {PositiveInteger} N - number of indexed elements 37 * @param {Float64Array} x - input array 38 * @param {integer} stride - stride length 39 * @param {NonNegativeInteger} offset - starting index 40 * @returns {number} arithmetic mean 41 * 42 * @example 43 * var Float64Array = require( '@stdlib/array/float64' ); 44 * var floor = require( '@stdlib/math/base/special/floor' ); 45 * 46 * var x = new Float64Array( [ 2.0, 1.0, 2.0, -2.0, -2.0, 2.0, 3.0, 4.0, NaN ] ); 47 * var N = floor( x.length / 2 ); 48 * 49 * var v = dnanmeanpw( N, x, 2, 1 ); 50 * // returns 1.25 51 */ 52 function dnanmeanpw( N, x, stride, offset ) { 53 WORKSPACE[ 0 ] = 0.0; 54 WORKSPACE[ 1 ] = 0; 55 dnansumpw( N, WORKSPACE, x, stride, offset ); 56 return WORKSPACE[ 0 ] / WORKSPACE[ 1 ]; 57 } 58 59 60 // EXPORTS // 61 62 module.exports = dnanmeanpw;