third_party/ulib/musl/src/complex/ctan.c

#include "libm.h"

/* tan(z) = -i tanh(i z) */

double complex ctan(double complex z) {
    z = ctanh(CMPLX(-cimag(z), creal(z)));
    return CMPLX(cimag(z), -creal(z));
}