include/gmxcomplex.h

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  38 #ifndef _gmxcomplex_h
  39 #define _gmxcomplex_h
  40
  41 #include <math.h>
  42 #include "typedefs.h"
  43
  44 typedef struct {
  45     real re, im;
  46 } t_complex;
  47
  48 typedef t_complex cvec[DIM];
  49
  50 static t_complex cnul = { 0.0, 0.0 };
  51
  52 static t_complex rcmul(real r, t_complex c)
  53 {
  54     t_complex d;
  55
  56     d.re = r*c.re;
  57     d.im = r*c.im;
  58
  59     return d;
  60 }
  61
  62 static t_complex rcexp(real r)
  63 {
  64     t_complex c;
  65
  66     c.re = (real)cos(r);
  67     c.im = (real)sin(r);
  68
  69     return c;
  70 }
  71
  72
  73 static t_complex cadd(t_complex a, t_complex b)
  74 {
  75     t_complex c;
  76
  77     c.re = a.re+b.re;
  78     c.im = a.im+b.im;
  79
  80     return c;
  81 }
  82
  83 static t_complex csub(t_complex a, t_complex b)
  84 {
  85     t_complex c;
  86
  87     c.re = a.re-b.re;
  88     c.im = a.im-b.im;
  89
  90     return c;
  91 }
  92
  93 static t_complex cmul(t_complex a, t_complex b)
  94 {
  95     t_complex c;
  96
  97     c.re = a.re*b.re - a.im*b.im;
  98     c.im = a.re*b.im + a.im*b.re;
  99
 100     return c;
 101 }
 102
 103 static t_complex conjugate(t_complex c)
 104 {
 105     t_complex d;
 106
 107     d.re =  c.re;
 108     d.im = -c.im;
 109
 110     return d;
 111 }
 112
 113 static real cabs2(t_complex c)
 114 {
 115     real abs2;
 116     abs2 = (c.re*c.re)+(c.im*c.im);
 117
 118     return abs2;
 119 }
 120
 121
 122
 123 static t_complex cdiv(t_complex teller, t_complex noemer)
 124 {
 125     t_complex res, anoemer;
 126
 127     anoemer = cmul(conjugate(noemer), noemer);
 128     res     = cmul(teller, conjugate(noemer));
 129
 130     return rcmul(1.0/anoemer.re, res);
 131 }
 132 #endif