75 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// <valarray>10 11// template<class T> class valarray;12 13// valarray operator[](const valarray<size_t>& vs) const;14 15#include <valarray>16#include <cassert>17 18#include "test_macros.h"19 20int main(int, char**)21{22 {23 int a[] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,24 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,25 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,26 36, 37, 38, 39, 40};27 const std::size_t N1 = sizeof(a)/sizeof(a[0]);28 std::size_t s[] = { 3, 4, 5, 7, 8, 9, 11, 12, 13, 15, 16, 17,29 22, 23, 24, 26, 27, 28, 30, 31, 32, 34, 35, 36};30 const std::size_t S = sizeof(s)/sizeof(s[0]);31 const std::valarray<int> v1(a, N1);32 std::valarray<std::size_t> ia(s, S);33 std::valarray<int> v = v1[ia];34 assert(v.size() == 24);35 assert(v[ 0] == 3);36 assert(v[ 1] == 4);37 assert(v[ 2] == 5);38 assert(v[ 3] == 7);39 assert(v[ 4] == 8);40 assert(v[ 5] == 9);41 assert(v[ 6] == 11);42 assert(v[ 7] == 12);43 assert(v[ 8] == 13);44 assert(v[ 9] == 15);45 assert(v[10] == 16);46 assert(v[11] == 17);47 assert(v[12] == 22);48 assert(v[13] == 23);49 assert(v[14] == 24);50 assert(v[15] == 26);51 assert(v[16] == 27);52 assert(v[17] == 28);53 assert(v[18] == 30);54 assert(v[19] == 31);55 assert(v[20] == 32);56 assert(v[21] == 34);57 assert(v[22] == 35);58 assert(v[23] == 36);59 }60 {61 int raw_data[] = {0,1,2,3,4,5,6,7,8,9};62 std::size_t idx_data[] = {0,2,4,6,8};63 const std::valarray<int> data(raw_data, sizeof(raw_data)/sizeof(raw_data[0]));64 std::valarray<std::size_t> idx(idx_data, sizeof(idx_data)/sizeof(idx_data[0]));65 std::valarray<int> result = (data + 0)[idx];66 assert(result.size() == 5);67 assert(result[0] == data[idx[0]]);68 assert(result[1] == data[idx[1]]);69 assert(result[2] == data[idx[2]]);70 assert(result[3] == data[idx[3]]);71 assert(result[4] == data[idx[4]]);72 }73 return 0;74}75