Bug fix: NeumannBC and RobinBC

Author: lululxvi

deepxde/icbc/boundary_conditions.py

@@ -51,7 +51,7 @@ def collocation_points(self, X):
 
     def normal_derivative(self, X, inputs, outputs, beg, end):
         dydx = grad.jacobian(outputs, inputs, i=self.component, j=None)[beg:end]
-        n = self.boundary_normal(X, beg, end)
+        n = self.boundary_normal(X, beg, end, None)
         return bkd.sum(dydx * n, 1, keepdims=True)
 
     @abstractmethod