include/gmxcomplex.h

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