ndarray.js (2451B)
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 single-precision floating-point strided array elements, ignoring `NaN` values, using ordinary recursive summation with extended accumulation, and returning an extended precision result. 30 * 31 * @param {PositiveInteger} N - number of indexed elements 32 * @param {Float32Array} x - input array 33 * @param {integer} strideX - `x` stride length 34 * @param {NonNegativeInteger} offsetX - `x` starting index 35 * @param {Float64Array} out - output array 36 * @param {integer} strideOut - `out` stride length 37 * @param {NonNegativeInteger} offsetOut - `out` starting index 38 * @returns {Float64Array} output array 39 * 40 * @example 41 * var Float32Array = require( '@stdlib/array/float32' ); 42 * var Float64Array = require( '@stdlib/array/float64' ); 43 * var floor = require( '@stdlib/math/base/special/floor' ); 44 * 45 * var x = new Float32Array( [ 2.0, 1.0, 2.0, -2.0, -2.0, 2.0, 3.0, 4.0, NaN, NaN ] ); 46 * var out = new Float64Array( 2 ); 47 * 48 * var N = floor( x.length / 2 ); 49 * 50 * var v = dsnannsumors( N, x, 2, 1, out, 1, 0 ); 51 * // returns <Float64Array>[ 5.0, 4 ] 52 */ 53 function dsnannsumors( N, x, strideX, offsetX, out, strideOut, offsetOut ) { 54 var sum; 55 var ix; 56 var io; 57 var n; 58 var i; 59 60 ix = offsetX; 61 io = offsetOut; 62 63 sum = 0.0; 64 if ( N <= 0 ) { 65 out[ io ] = sum; 66 out[ io+strideOut ] = 0; 67 return out; 68 } 69 if ( N === 1 || strideX === 0 ) { 70 if ( isnan( x[ ix ] ) ) { 71 out[ io ] = sum; 72 out[ io+strideOut ] = 0; 73 return out; 74 } 75 out[ io ] = x[ ix ]; 76 out[ io+strideOut ] = 1; 77 return out; 78 } 79 n = 0; 80 for ( i = 0; i < N; i++ ) { 81 if ( isnan( x[ ix ] ) === false ) { 82 sum += x[ ix ]; 83 n += 1; 84 } 85 ix += strideX; 86 } 87 out[ io ] = sum; 88 out[ io+strideOut ] = n; 89 return out; 90 } 91 92 93 // EXPORTS // 94 95 module.exports = dsnannsumors;