amath  1.8.5
Simple command line calculator
ahv.c
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2  * Copyright (c) 2014-2018 Carsten Sonne Larsen <cs@innolan.net>
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29 
30 /**
31  * @file ahv.c
32  * @brief Inverse haversed sine
33  */
34 
35 #include "prim.h"
36 
37 /**
38  * @brief Inverse haversed sine
39  */
40 double ahv(double x)
41 {
42  double a = x - x * x;
43  double b = 2.0 * sqrt(a);
44  double c = 1.0 - 2.0 * x;
45  double d = atan(b / c);
46  return d;
47 }
double sqrt(double x)
Square root function.
Definition: sqrt.c:119
double atan(double x)
Inverse tangent function.
Definition: atan.c:103
double ahv(double x)
Inverse haversed sine.
Definition: ahv.c:40