ctan(3)

NAME

ctan, ctanf, ctanl — complex circular tangent

/* -lm */
#include <complex.h>

double complex
ctan(double complex z);

float complex
ctanf(float complex z);

long double complex
ctanl(long double complex z);

The ctan(), ctanf() and ctanl() functions compute the complex circular tangent of z.

If z = x + iy, then

ctan(z) = (sin(2x) + i sinh(2y)) / (cos(2x) + cosh(2y)).

On the real axis the denominator is zero at odd multiples of Pi/2. The denominator is evaluated by its Taylor series near these points.

ctan(z) = -i ctanh(iz).

The ctan(), ctanf() and ctanl() functions return the complex circular tangent of z.

The ctan(), ctanf() and ctanl() functions conform to ISO/IEC 9899:1999 (“ISO C99”).