static RCP<const Basic> diff(const ATan &self, const RCP<const Symbol> &x) { return mul(div(one, add(one, pow(self.get_arg(), i2))), self.get_arg()->diff(x)); }
void bvisit(const ATan &x) { apply(result_, *(x.get_arg())); mpfr_atan(result_, result_, rnd_); }