static RCP<const Basic> diff(const Gamma &self, const RCP<const Symbol> &x) { RCP<const Basic> gamma_arg = self.get_args()[0]; return mul(mul(self.rcp_from_this(), polygamma(zero, gamma_arg)), gamma_arg->diff(x)); }
void bvisit(const Gamma &x) { apply(result_, *(x.get_args()[0])); mpfr_gamma(result_, result_, rnd_); };