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37 #ifndef GMX_MATH_GMXCOMPLEX_H
38 #define GMX_MATH_GMXCOMPLEX_H
39
40 #include <cmath>
41
42 #include "gromacs/math/vectypes.h"
43 #include "gromacs/utility/real.h"
44
45 struct t_complex
46 {
47 real re, im;
48 };
49
50 typedef t_complex cvec[DIM];
51
rcmul(real r,t_complex c)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
rcexp(real r)62 static inline t_complex rcexp(real r)
63 {
64 t_complex c;
65
66 c.re = cos(r);
67 c.im = sin(r);
68
69 return c;
70 }
71
72
cadd(t_complex a,t_complex b)73 static inline 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
csub(t_complex a,t_complex b)83 static inline 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
cmul(t_complex a,t_complex b)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
conjugate(t_complex c)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
cabs2(t_complex c)113 static inline 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
cdiv(t_complex teller,t_complex noemer)121 static inline t_complex cdiv(t_complex teller, t_complex noemer)
122 {
123 t_complex res, anoemer;
124
125 anoemer = cmul(conjugate(noemer), noemer);
126 res = cmul(teller, conjugate(noemer));
127
128 return rcmul(1.0 / anoemer.re, res);
129 }
130
131 inline bool operator==(const t_complex& lhs, const t_complex& rhs)
132 {
133 return (lhs.re == rhs.re) && (lhs.im == rhs.im);
134 }
135 inline bool operator!=(const t_complex& lhs, const t_complex& rhs)
136 {
137 return !(lhs == rhs);
138 }
139
140 #endif
141