How to smooth a 3d surface

How to smooth my 3d plot,i tried smooth function but it only works for 2dimensional.

Y is a 201x201 matrix
 Y= [201 201]
  x = 10:0.1:30;
  z = 1:0.01:3;
  [X,Z] = ndgrid(x,z);
  mesh(X,Z,smooth(Y))

Answer 1

[Benjamin Kraus]

Have you tried conv2?

[Joseph Lee]

Sorry, I'm not sure how to use it, i got an error following an example.

x = 10:0.1:30;
z = 1:0.01:3;
[X,Z] = ndgrid(x',z);
mesh(conv2(X,Z,(Y_3D)))
Error using conv2
The first and second arguments must be vectors when the third argument is a matrix.