libcxx/test/std/numerics/complex.number/complex.transcendentals/log.pass.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-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // <complex>
  10
  11 // template<class T>
  12 //   complex<T>
  13 //   log(const complex<T>& x);
  14
  15 #include <complex>
  16 #include <cassert>
  17
  18 #include "test_macros.h"
  19 #include "../cases.h"
  20
  21 template <class T>
  22 void
  23 test(const std::complex<T>& c, std::complex<T> x)
  24 {
  25     assert(log(c) == x);
  26 }
  27
  28 template <class T>
  29 void
  30 test()
  31 {
  32     test(std::complex<T>(0, 0), std::complex<T>(-INFINITY, 0));
  33 }
  34
  35 void test_edges()
  36 {
  37     const double pi = std::atan2(+0., -0.);
  38     const unsigned N = sizeof(testcases) / sizeof(testcases[0]);
  39     for (unsigned i = 0; i < N; ++i)
  40     {
  41         std::complex<double> r = log(testcases[i]);
  42         if (testcases[i].real() == 0 && testcases[i].imag() == 0)
  43         {
  44             if (std::signbit(testcases[i].real()))
  45             {
  46                 assert(std::isinf(r.real()));
  47                 assert(r.real() < 0);
  48                 if (std::signbit(testcases[i].imag()))
  49                     is_about(r.imag(), -pi);
  50                 else
  51                     is_about(r.imag(), pi);
  52             }
  53             else
  54             {
  55                 assert(std::isinf(r.real()));
  56                 assert(r.real() < 0);
  57                 assert(r.imag() == 0);
  58                 assert(std::signbit(testcases[i].imag()) == std::signbit(r.imag()));
  59             }
  60         }
  61         else if (std::isfinite(testcases[i].real()) && std::isinf(testcases[i].imag()))
  62         {
  63             assert(std::isinf(r.real()));
  64             assert(r.real() > 0);
  65             if (testcases[i].imag() > 0)
  66                 is_about(r.imag(), pi/2);
  67             else
  68                 is_about(r.imag(), -pi/2);
  69         }
  70         else if (std::isfinite(testcases[i].real()) && std::isnan(testcases[i].imag()))
  71         {
  72             assert(std::isnan(r.real()));
  73             assert(std::isnan(r.imag()));
  74         }
  75         else if (std::isinf(testcases[i].real()) && testcases[i].real() < 0 && std::isfinite(testcases[i].imag()))
  76         {
  77             assert(std::isinf(r.real()) && r.real() > 0);
  78             if (r.imag() > 0)
  79                 is_about(r.imag(), pi);
  80             else
  81                 is_about(r.imag(), -pi);
  82         }
  83         else if (std::isinf(testcases[i].real()) && testcases[i].real() > 0 && std::isfinite(testcases[i].imag()))
  84         {
  85             assert(std::isinf(r.real()) && r.real() > 0);
  86             assert(r.imag() == 0);
  87             assert(std::signbit(testcases[i].imag()) == std::signbit(r.imag()));
  88         }
  89         else if (testcases[i].real() == 1 && testcases[i].imag() == 0)
  90         {
  91             assert(r.real() == 0);
  92             assert(std::signbit(r.imag()) == std::signbit(testcases[i].imag()));
  93         }
  94         else if (testcases[i].real() == 0 && testcases[i].imag() == 1)
  95         {
  96             assert(r.real() == 0);
  97             is_about(r.imag(), pi/2);
  98         }
  99         else if (testcases[i].real() == -1 && testcases[i].imag() == 0)
 100         {
 101             assert(r.real() == 0);
 102             if (std::signbit(testcases[i].imag()))
 103                 is_about(r.imag(), -pi);
 104             else
 105                 is_about(r.imag(),  pi);
 106         }
 107         else if (testcases[i].real() == 0 && testcases[i].imag() == -1)
 108         {
 109             assert(r.real() == 0);
 110             is_about(r.imag(), -pi/2);
 111         }
 112         else if (std::isfinite(testcases[i].real()) && std::isfinite(testcases[i].imag()) && abs(testcases[i]) < 1)
 113         {
 114             assert( std::signbit(r.real()));
 115             assert(std::signbit(r.imag()) == std::signbit(testcases[i].imag()));
 116         }
 117         else if (std::isfinite(testcases[i].real()) && std::isfinite(testcases[i].imag()) && abs(testcases[i]) > 1)
 118         {
 119             assert(!std::signbit(r.real()));
 120             assert(std::signbit(r.imag()) == std::signbit(testcases[i].imag()));
 121         }
 122     }
 123 }
 124
 125 int main(int, char**)
 126 {
 127     test<float>();
 128     test<double>();
 129     test<long double>();
 130     test_edges();
 131
 132   return 0;
 133 }