I know you can do these fairly easy in Mathematica and I've also seen some code for it in Matlab.
Here's an example for Mathematica that should work:
nx = 2
ny = 2
Plot3D[
Sin[nx Pi x]Sin[ny Pi y],
{x, 0, 1},
{y, 0, 1},
ImageSize -> '''250''',
BoxRatios -> {2, 2, 2}...