# catanhf, catanh, catanhl

< c‎ | numeric‎ | complex

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Complex number arithmetic
Types and the imaginary constant
Manipulation
Power and exponential functions
Trigonometric functions
Hyperbolic functions
 cacosh casinh catanh

 Defined in header `` float complex       catanhf( float complex z ); (since C99) double complex      catanh( double complex z ); (since C99) long double complex catanhl( long double complex z ); (since C99)

Computes the complex arc hyperbolic tangent of `z` with branch cuts outside the interval [−1; +1] along the real axis.

## Contents

### Parameters

 z - complex argument

### Return value

The complex arc hyperbolic tangent of `z` in the interval (−∞; +∞) along the real axis and in the interval [−iπ/2; +iπ/2] along the imaginary axis.

### Example

```#include <stdio.h>
#include <complex.h>

int main(void)
{
double complex z;

z = ctanh(1.0+2.0*I);
printf("ctanh(1.0+2.0*I)            ==> %f%+fi\n", creal(z),cimag(z));

z = catanh(1.166736-0.243458*I);
printf("catanh(1.166736-0.243458*I) ==> %f%+fi\n", creal(z),cimag(z));

return 0;
}```

Output:

```ctanh(1.0+2.0*I)            ==> 1.166736-0.243458i
catanh(1.166736-0.243458*I) ==> 1.000000-1.141592i```