gcc/d/dmd/complex_t.h

   1
   2 /* Compiler implementation of the D programming language
   3  * Copyright (C) 1999-2021 by The D Language Foundation, All Rights Reserved
   4  * written by Walter Bright
   5  * http://www.digitalmars.com
   6  * Distributed under the Boost Software License, Version 1.0.
   7  * http://www.boost.org/LICENSE_1_0.txt
   8  * https://github.com/dlang/dmd/blob/master/src/dmd/complex_t.h
   9  */
  10
  11 #pragma once
  12
  13 #include "root/ctfloat.h"
  14
  15 /* Roll our own complex type for compilers that don't support complex
  16  */
  17
  18 struct complex_t
  19 {
  20     real_t re;
  21     real_t im;
  22
  23     complex_t(real_t re) : re(re), im(ldouble(0)) {}
  24     complex_t(real_t re, real_t im) : re(re), im(im) {}
  25
  26     complex_t operator + (complex_t y) { return complex_t(re + y.re, im + y.im); }
  27     complex_t operator - (complex_t y) { return complex_t(re - y.re, im - y.im); }
  28     complex_t operator - () { return complex_t(-re, -im); }
  29     complex_t operator * (complex_t y) { return complex_t(re * y.re - im * y.im, im * y.re + re * y.im); }
  30
  31     complex_t operator / (complex_t y)
  32     {
  33         if (CTFloat::fabs(y.re) < CTFloat::fabs(y.im))
  34         {
  35             real_t r = y.re / y.im;
  36             real_t den = y.im + r * y.re;
  37             return complex_t((re * r + im) / den,
  38                              (im * r - re) / den);
  39         }
  40         else
  41         {
  42             real_t r = y.im / y.re;
  43             real_t den = y.re + r * y.im;
  44             return complex_t((re + r * im) / den,
  45                              (im - r * re) / den);
  46         }
  47     }
  48
  49     operator bool () { return re || im; }
  50
  51     int operator == (complex_t y) { return re == y.re && im == y.im; }
  52     int operator != (complex_t y) { return re != y.re || im != y.im; }
  53
  54 private:
  55     complex_t() : re(ldouble(0)), im(ldouble(0)) {}
  56 };
  57
  58 inline complex_t operator * (real_t x, complex_t y) { return complex_t(x) * y; }
  59 inline complex_t operator * (complex_t x, real_t y) { return x * complex_t(y); }
  60 inline complex_t operator / (complex_t x, real_t y) { return x / complex_t(y); }
  61
  62
  63 inline real_t creall(complex_t x)
  64 {
  65     return x.re;
  66 }
  67
  68 inline real_t cimagl(complex_t x)
  69 {
  70     return x.im;
  71 }