C library function atanh() usage and example

Biblioteca Padrão <math.h> C

The atanh() function returns the inverse hyperbolic arctangent (inverse hyperbolic tangent value) of the radian number.

The atanh() function uses a single parameter (-1≤x≥1），and returns the inverse hyperbolic arctangent value in radians.

The atanh() function is included in the <math.h> header file.

atanh() prototype

double　atanh(double　x);

To find the hyperbolic arctangent of type int, float, or long double, you can use the cast operator to explicitly convert the type to double.

　int　x　=　0;
　double　result;
　result　=　atanh(double(x));

Additionally, C99Two functions atanhf() and atanhl() are introduced in C, which are specifically used for float and long double types.

float　atanhf(float　x);
long　double　atanhl(long　double　x);

atanh() parameter

The atanh() function uses a parameter greater than or equal to-1and less than or equal to1parameter.

Example1atanh() function with different parameters

#include　<stdio.h>
#include　<math.h>
int　main()
{
　　　　//PI　constant
　　　　const　double　PI　=　　3.1415926;
　　　　double　x,　result;
　　　　x =　　-0.5;
　　　　result = atanh(x);
　　　　printf("atanh(%.2f) = %.2lf　radians\n",　x,　result);
　　　　//Convert degrees to radians
　　　　result　=　atanh(x)*180/PI;
　　　　printf("atanh(%.2f) = %.2lf degree\n",　x,　result);
　　　　//Parâmetro fora do intervalo
　　　　x =　3;
　　　　result = atanh(x);
　　　　printf("atanh(%.2f) = %.2lf", x, result);
　　　　return 0;
}

Resultados de Saída

atanh(-0.50) =　-0.55　Radianos
atanh(-0.50) =　-31.47　Graus
atanh(3.00) = nan

Biblioteca Padrão <math.h> C