llvm-project/libcxx/test/numerics/complex.number/complex.value.ops/arg.pass.cpp

136 lines
3.7 KiB
C++

//===----------------------------------------------------------------------===//
//
// 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.
//
//===----------------------------------------------------------------------===//
// <complex>
// template<class T>
// T
// arg(const complex<T>& x);
#include <complex>
#include <cassert>
#include "../cases.h"
template <class T>
void
test()
{
std::complex<T> z(1, 0);
assert(arg(z) == 0);
}
void test_edges()
{
const double pi = std::atan2(+0., -0.);
const unsigned N = sizeof(x) / sizeof(x[0]);
for (unsigned i = 0; i < N; ++i)
{
double r = arg(x[i]);
if (std::isnan(x[i].real()) || std::isnan(x[i].imag()))
assert(std::isnan(r));
else
{
switch (classify(x[i]))
{
case zero:
if (std::signbit(x[i].real()))
{
if (std::signbit(x[i].imag()))
is_about(r, -pi);
else
is_about(r, pi);
}
else
{
assert(std::signbit(x[i].imag()) == std::signbit(r));
}
break;
case non_zero:
if (x[i].real() == 0)
{
if (x[i].imag() < 0)
is_about(r, -pi/2);
else
is_about(r, pi/2);
}
else if (x[i].imag() == 0)
{
if (x[i].real() < 0)
{
if (std::signbit(x[i].imag()))
is_about(r, -pi);
else
is_about(r, pi);
}
else
{
assert(r == 0);
assert(std::signbit(x[i].imag()) == std::signbit(r));
}
}
else if (x[i].imag() > 0)
assert(r > 0);
else
assert(r < 0);
break;
case inf:
if (std::isinf(x[i].real()) && std::isinf(x[i].imag()))
{
if (x[i].real() < 0)
{
if (x[i].imag() > 0)
is_about(r, 0.75 * pi);
else
is_about(r, -0.75 * pi);
}
else
{
if (x[i].imag() > 0)
is_about(r, 0.25 * pi);
else
is_about(r, -0.25 * pi);
}
}
else if (std::isinf(x[i].real()))
{
if (x[i].real() < 0)
{
if (std::signbit(x[i].imag()))
is_about(r, -pi);
else
is_about(r, pi);
}
else
{
assert(r == 0);
assert(std::signbit(r) == std::signbit(x[i].imag()));
}
}
else
{
if (x[i].imag() < 0)
is_about(r, -pi/2);
else
is_about(r, pi/2);
}
break;
}
}
}
}
int main()
{
test<float>();
test<double>();
test<long double>();
test_edges();
}