1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <valarray> 11 12 // template<class T> class valarray; 13 14 // template<class T> 15 // valarray<T> 16 // pow(const valarray<T>& x, const T& y); 17 18 #include <valarray> 19 #include <cassert> 20 #include <sstream> 21 #include <cstddef> 22 23 bool is_about(double x, double y, int p) 24 { 25 std::ostringstream o; 26 o.precision(p); 27 scientific(o); 28 o << x; 29 std::string a = o.str(); 30 o.str(""); 31 o << y; 32 return a == o.str(); 33 } 34 35 int main() 36 { 37 { 38 typedef double T; 39 T a1[] = {.9, .5, 0., .5, .75}; 40 T a3[] = {8.1000000000000005e-01, 41 2.5000000000000000e-01, 42 0.0000000000000000e+00, 43 2.5000000000000000e-01, 44 5.6250000000000000e-01}; 45 const unsigned N = sizeof(a1)/sizeof(a1[0]); 46 std::valarray<T> v1(a1, N); 47 std::valarray<T> v3 = pow(v1, 2.0); 48 assert(v3.size() == v1.size()); 49 for (std::size_t i = 0; i < v3.size(); ++i) 50 assert(is_about(v3[i], a3[i], 10)); 51 } 52 } 53
