CATAN

Section: Linux Programmer's Manual (3)
Updated: 2008-08-11
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NAME

catan, catanf, catanl - complex arc tangents

SYNOPSIS

#include <complex.h>

double complex catan(double complex z);
float complex catanf(float complex z);
long double complex catanl(long double complex z);

Link with -lm.

DESCRIPTION

The catan() function calculates the complex arc tangent of z. If y = catan(z), then z = ctan(y). The real part of y is chosen in the interval [-pi/2,pi/2].

One has:


    catan(z) = 1 / 2i clog((1 + iz) / (1 - iz))

VERSIONS

These functions first appeared in glibc in version 2.1.

CONFORMING TO

C99.

COLOPHON

This page is part of release 3.22 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.