amath  1.8.5
Simple command line calculator
csech.c
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1 /*-
2  * Copyright (c) 2014-2018 Carsten Sonne Larsen <cs@innolan.net>
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29 
30 #include "prim.h"
31 
32 /**
33  * @brief Hyperbolic secant of a complex number
34  * @details
35  * Calculated as in Open Office:<BR>
36  * https://wiki.openoffice.org/wiki/Documentation/How_Tos/Calc:_IMSECH_function
37  * <pre>
38  * a+bi
39  * 2.0 * cosh(a) * cos(b)
40  * real = ------------------------------
41  * cosh(2.0 * a) + cos(2.0 * b)
42  *
43  * -2.0 * sinh(2.0 * a) * sin(b)
44  * imag = ------------------------------
45  * cosh(2.0 * a) + cos(2.0 * b)
46  * </pre>
47  */
48 complex csech(complex z)
49 {
50  complex w;
51  double a, b;
52  double d;
53 
54  a = creal(z);
55  b = cimag(z);
56  d = cosh(2.0 * a) + cos(2.0 * b);
57  w = cpack((2.0 * cosh(a) * cos(b) / d), (-2.0 * sinh(a) * sin(b) / d));
58 
59  return w;
60 }
complex csech(complex z)
Hyperbolic secant of a complex number.
Definition: csech.c:48
double cos(double x)
Cosine function.
Definition: cos.c:87
double creal(complex z)
Real part of complex number.
Definition: prim.c:38
double sinh(double x)
Hyperbolic sine function.
Definition: sinh.c:77
complex cpack(double x, double y)
Pack two real numbers into a complex number.
Definition: prim.c:68
double cimag(complex z)
Imaginary part of complex number.
Definition: prim.c:46
double cosh(double x)
Hyperbolic cosine function.
Definition: cosh.c:83
double sin(double x)
Sine function.
Definition: sin.c:86