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      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 // <complex>
     11 
     12 // template<class T>
     13 //   complex<T>
     14 //   log(const complex<T>& x);
     15 
     16 #include <complex>
     17 #include <cassert>
     18 
     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()
    126 {
    127     test<float>();
    128     test<double>();
    129     test<long double>();
    130     test_edges();
    131 }
    132