snansumors.c (1496B)
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 #include "stdlib/blas/ext/base/snansumors.h" 20 #include "stdlib/math/base/assert/is_nanf.h" 21 #include <stdint.h> 22 23 /** 24 * Computes the sum of single-precision floating-point strided array elements, ignoring `NaN` values and using ordinary recursive summation. 25 * 26 * @param N number of indexed elements 27 * @param X input array 28 * @param stride stride length 29 * @return output value 30 */ 31 float stdlib_strided_snansumors( const int64_t N, const float *X, const int64_t stride ) { 32 int64_t ix; 33 int64_t i; 34 float sum; 35 36 sum = 0.0f; 37 if ( N <= 0 ) { 38 return sum; 39 } 40 if ( N == 1 || stride == 0 ) { 41 if ( stdlib_base_is_nanf( X[ 0 ] ) ) { 42 return sum; 43 } 44 return X[ 0 ]; 45 } 46 if ( stride < 0 ) { 47 ix = (1-N) * stride; 48 } else { 49 ix = 0; 50 } 51 for ( i = 0; i < N; i++ ) { 52 if ( !stdlib_base_is_nanf( X[ ix ] ) ) { 53 sum += X[ ix ]; 54 } 55 ix += stride; 56 } 57 return sum; 58 }