Function AtanhGrad

tensorflow/cc/gradients/math_grad.cc:240–251

REGISTER_GRADIENT_OP("Acosh", AcoshGrad);

Status AtanhGrad(const Scope& scope, const Operation& op,
                 const std::vector<Output>& grad_inputs,
                 std::vector<Output>* grad_outputs) {
  // y = atanh(x)
  // dy/dx = 1 / (1 - x^2)
  auto one = Cast(scope, Const(scope, 1.0), op.input(0).type());
  auto dydx = Reciprocal(scope, Sub(scope, one, Square(scope, op.input(0))));
  // grad(x) = grad(y) * conj(dy/dx)
  grad_outputs->push_back(
      Mul(scope, grad_inputs[0], ConjugateHelper(scope, dydx)));
  return scope.status();
}
REGISTER_GRADIENT_OP("Atanh", AtanhGrad);

Status Atan2Grad(const Scope& scope, const Operation& op,