_cacos_sub _cacosh_sub _casin_sub _casinh_sub _catan_sub _catanh_sub _ccos_sub _ccosh_sub _ccot _ccot_sub _cexp_sub _cexpm1 _cexpm1_sub _clog1p _clog1p_sub _clog_sub _csin_sub _csinh_sub _ctan_sub _ctanh_sub

_catan_sub() void _catan_sub ( double _Complex  z, double _Complex *  atanz  ) atan(z) of complex number Purpose catan_sub is the subroutine version of C99 function catan. Parameters [in] z Complex argument z. [out] atanz atan(z).