src/gromacs/math/gmxcomplex.h

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