dnannsumors.js (2158B)
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 isnan = require( '@stdlib/math/base/assert/is-nan' ); 24 25 26 // MAIN // 27 28 /** 29 * Computes the sum of double-precision floating-point strided array elements, ignoring `NaN` values and using ordinary recursive summation. 30 * 31 * @param {PositiveInteger} N - number of indexed elements 32 * @param {Float64Array} x - input array 33 * @param {integer} strideX - `x` stride length 34 * @param {Float64Array} out - output array 35 * @param {integer} strideOut - `out` stride length 36 * @returns {Float64Array} output array 37 * 38 * @example 39 * var Float64Array = require( '@stdlib/array/float64' ); 40 * 41 * var x = new Float64Array( [ 1.0, -2.0, NaN, 2.0 ] ); 42 * var out = new Float64Array( 2 ); 43 * 44 * var v = dnannsumors( x.length, x, 1, out, 1 ); 45 * // returns <Float64Array>[ 1.0, 3 ] 46 */ 47 function dnannsumors( N, x, strideX, out, strideOut ) { 48 var sum; 49 var ix; 50 var io; 51 var n; 52 var i; 53 54 if ( strideX < 0 ) { 55 ix = (1-N) * strideX; 56 } else { 57 ix = 0; 58 } 59 if ( strideOut < 0 ) { 60 io = -strideOut; 61 } else { 62 io = 0; 63 } 64 sum = 0.0; 65 if ( N <= 0 ) { 66 out[ io ] = sum; 67 out[ io+strideOut ] = 0; 68 return out; 69 } 70 if ( N === 1 || strideX === 0 ) { 71 if ( isnan( x[ ix ] ) ) { 72 out[ io ] = sum; 73 out[ io+strideOut ] = 0; 74 return out; 75 } 76 out[ io ] = x[ ix ]; 77 out[ io+strideOut ] = 1; 78 return out; 79 } 80 n = 0; 81 for ( i = 0; i < N; i++ ) { 82 if ( isnan( x[ ix ] ) === false ) { 83 sum += x[ ix ]; 84 n += 1; 85 } 86 ix += strideX; 87 } 88 out[ io ] = sum; 89 out[ io+strideOut ] = n; 90 return out; 91 } 92 93 94 // EXPORTS // 95 96 module.exports = dnannsumors;