include/gmxcomplex.h

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  35 #ifndef _complex_h
  36 #define _complex_h
  37
  38 #include <math.h>
  39 #include "typedefs.h"
  40
  41 typedef struct {
  42   real re,im;
  43 } t_complex;
  44
  45 typedef t_complex cvec[DIM];
  46
  47 static t_complex cnul = { 0.0, 0.0 };
  48
  49 static t_complex rcmul(real r,t_complex c)
  50 {
  51   t_complex d;
  52
  53   d.re = r*c.re;
  54   d.im = r*c.im;
  55
  56   return d;
  57 }
  58
  59 static t_complex rcexp(real r)
  60 {
  61   t_complex c;
  62
  63   c.re = (real)cos(r);
  64   c.im = (real)sin(r);
  65
  66   return c;
  67 }
  68
  69
  70 static t_complex cadd(t_complex a,t_complex b)
  71 {
  72   t_complex c;
  73
  74   c.re = a.re+b.re;
  75   c.im = a.im+b.im;
  76
  77   return c;
  78 }
  79
  80 static t_complex csub(t_complex a,t_complex b)
  81 {
  82   t_complex c;
  83
  84   c.re = a.re-b.re;
  85   c.im = a.im-b.im;
  86
  87   return c;
  88 }
  89
  90 static t_complex cmul(t_complex a,t_complex b)
  91 {
  92   t_complex c;
  93
  94   c.re = a.re*b.re - a.im*b.im;
  95   c.im = a.re*b.im + a.im*b.re;
  96
  97   return c;
  98 }
  99
 100 static t_complex conjugate(t_complex c)
 101 {
 102   t_complex d;
 103
 104   d.re =  c.re;
 105   d.im = -c.im;
 106
 107   return d;
 108 }
 109
 110 static t_complex cdiv(t_complex teller,t_complex noemer)
 111 {
 112   t_complex res,anoemer;
 113
 114   anoemer = cmul(conjugate(noemer),noemer);
 115   res = cmul(teller,conjugate(noemer));
 116
 117   return rcmul(1.0/anoemer.re,res);
 118 }
 119 #endif