Um, I don't think so. 'interp' will use interpolated coloring, which will do no smoothing. Smoothing is a technique where you replace existing values with ones that are close, but that yield a smoother resulting surface. Interpolation does not change the data at the nodes.
To do actual smoothing, where the nodal values are allowed to change (though not move in space) will take some thought.
If I understand you correctly. you have a triangulated surface in R^3, thus (x,y,z), and at each node you have a value w, where w is presumed to have some additive component of noise. Your goal is to arrive at a smoother set of values w(x,y,z), where only w has been smoothed but the triangulation is left untouched? An example of what I am describing is a triangulation, perhaps on the surface of a sphere, where each node also has an associated 4th value, w. Only w will be smoothed? So perhaps you have measured temperature at a triangulated set of points on the surface of the earth, and your goal is to smooth the temperatures. That is how I would interpret what you've said, but it is often true that what someone says and what they really want are two things completely at odds with each other.
