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 // atan2(const valarray<T>& x, const valarray<T>& y); 17 18 #include <valarray> 19 #include <cassert> 20 #include <sstream> 21 22 bool is_about(double x, double y, int p) 23 { 24 std::ostringstream o; 25 o.precision(p); 26 scientific(o); 27 o << x; 28 std::string a = o.str(); 29 o.str(""); 30 o << y; 31 return a == o.str(); 32 } 33 34 int main() 35 { 36 { 37 typedef double T; 38 T a1[] = {-.9, -.5, 0., .5, .75}; 39 T a2[] = {-.8, .25, 0.375, -.5, .75}; 40 T a3[] = {-2.2974386674766221e+00, 41 -1.1071487177940904e+00, 42 0.0000000000000000e+00, 43 2.3561944901923448e+00, 44 7.8539816339744828e-01}; 45 const unsigned N = sizeof(a1)/sizeof(a1[0]); 46 std::valarray<T> v1(a1, N); 47 std::valarray<T> v2(a2, N); 48 std::valarray<T> v3 = atan2(v1, v2); 49 assert(v3.size() == v1.size()); 50 for (int i = 0; i < v3.size(); ++i) 51 assert(is_about(v3[i], a3[i], 10)); 52 } 53 } 54
