I'm sorry - that was a typo: I meant gridfit when I typed griddata. I since figured it out it was a MATLAB environment issue, unrelated to gridfit. Contour plots just weren't showing up in the display. Restart solved the problem. I would edit or remove my original post, but this forum doesn't allow for it. Thanks for the quick reply.
I'm trying to use gridfit to produce a contour map (functions: contour and contourf). MATLAB seems to interpret the griddata output okay for the surf() function, but fails with contour(). Anyone else run into this problem? I think it has something to do with grid orientation.