catan(), catanf(), catanl()

Compute the complex arc tangent

Synopsis:

#include <complex.h>

double complex catan( double complex z );

float complex catanf( float complex z );

long double complex catanl( long double complex z );

Arguments:

z: The value that you want to get the complex arc tangent of.

Library:

libm

Use the -l m option to qcc to link against this library.

Description:

These functions compute the complex arc tangent of z, with branch cuts outside the interval [−i,+i] along the imaginary axis.

To check for error situations, use feclearexcept() and fetestexcept(). For example:

Call feclearexcept(FE_ALL_EXCEPT) before calling catan(), catanf(), or catanl().
On return, if fetestexcept(FE_ALL_EXCEPT) is nonzero, then an error has occurred.

Returns:

The complex arc tangent of z, in the range of a strip unbounded along the imaginary axis and in the interval [−π/2; +π/2] along the real axis.

Errors and special cases are handled as if the operation were implemented as -i * catanh(i * z).

These functions raise FE_INEXACT if the FPU reports that the result can't be exactly represented as a floating-point number.

Classification:

ANSI, POSIX 1003.1

Safety:
Cancellation point	No
Interrupt handler	No
Signal handler	No
Thread	Yes