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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <valarray>
// template<class T> class valarray;
// template<class T>
// valarray<T>
// atan2(const valarray<T>& x, const T& y);
#include <valarray>
#include <cassert>
#include <sstream>
bool is_about(double x, double y, int p)
{
std::ostringstream o;
o.precision(p);
scientific(o);
o << x;
std::string a = o.str();
o.str("");
o << y;
return a == o.str();
}
int main()
{
{
typedef double T;
T a1[] = {-.9, -.5, 0., .5, .75};
T a3[] = {-8.7605805059819342e-01,
-5.8800260354756750e-01,
0.0000000000000000e+00,
5.8800260354756750e-01,
7.8539816339744828e-01};
const unsigned N = sizeof(a1)/sizeof(a1[0]);
std::valarray<T> v1(a1, N);
std::valarray<T> v3 = atan2(v1, .75);
assert(v3.size() == v1.size());
for (int i = 0; i < v3.size(); ++i)
assert(is_about(v3[i], a3[i], 10));
}
}
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