github.com/afumu/libc@v0.0.6/musl/src/complex/ctan.c (about)

     1  #include "complex_impl.h"
     2  
     3  /* tan(z) = -i tanh(i z) */
     4  
     5  double complex ctan(double complex z)
     6  {
     7  	z = ctanh(CMPLX(-cimag(z), creal(z)));
     8  	return CMPLX(cimag(z), -creal(z));
     9  }