1 .\" Copyright 2002 Walter Harms (walter.harms@informatik.uni-oldenburg.de)
2 .\" Distributed under GPL
4 .TH CATAN 3 2011-09-15 "" "Linux Programmer's Manual"
6 catan, catanf, catanl \- complex arc tangents
8 .B #include <complex.h>
10 .BI "double complex catan(double complex " z );
12 .BI "float complex catanf(float complex " z );
14 .BI "long double complex catanl(long double complex " z );
20 function calculates the complex arc tangent of
22 If \fIy\ =\ catan(z)\fP, then \fIz\ =\ ctan(y)\fP.
23 The real part of y is chosen in the interval [\-pi/2,pi/2].
28 catan(z) = (clog(1 + i * z) \- clog(1 \- i * z)) / (2 * i)
31 These functions first appeared in glibc in version 2.1.