include/gmxcomplex.h

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  36 #ifndef _complex_h
  37 #define _complex_h
  38
  39 #ifdef HAVE_CONFIG_H
  40 #include <config.h>
  41 #endif
  42
  43 #include <math.h>
  44 #include "typedefs.h"
  45
  46 typedef struct {
  47   real re,im;
  48 } t_complex;
  49
  50 typedef t_complex cvec[DIM];
  51
  52 static t_complex cnul = { 0.0, 0.0 };
  53
  54 static t_complex rcmul(real r,t_complex c)
  55 {
  56   t_complex d;
  57
  58   d.re = r*c.re;
  59   d.im = r*c.im;
  60
  61   return d;
  62 }
  63
  64 static t_complex rcexp(real r)
  65 {
  66   t_complex c;
  67
  68   c.re = cos(r);
  69   c.im = sin(r);
  70
  71   return c;
  72 }
  73
  74
  75 static t_complex cadd(t_complex a,t_complex b)
  76 {
  77   t_complex c;
  78
  79   c.re = a.re+b.re;
  80   c.im = a.im+b.im;
  81
  82   return c;
  83 }
  84
  85 static t_complex csub(t_complex a,t_complex b)
  86 {
  87   t_complex c;
  88
  89   c.re = a.re-b.re;
  90   c.im = a.im-b.im;
  91
  92   return c;
  93 }
  94
  95 static t_complex cmul(t_complex a,t_complex b)
  96 {
  97   t_complex c;
  98
  99   c.re = a.re*b.re - a.im*b.im;
 100   c.im = a.re*b.im + a.im*b.re;
 101
 102   return c;
 103 }
 104
 105 static t_complex conjugate(t_complex c)
 106 {
 107   t_complex d;
 108
 109   d.re =  c.re;
 110   d.im = -c.im;
 111
 112   return d;
 113 }
 114
 115 static t_complex cdiv(t_complex teller,t_complex noemer)
 116 {
 117   t_complex res,anoemer;
 118
 119   anoemer = cmul(conjugate(noemer),noemer);
 120   res = cmul(teller,conjugate(noemer));
 121
 122   return rcmul(1.0/anoemer.re,res);
 123 }
 124 #endif