Custom fitting equations: Using a TriScatteredInterp Object

For a while now I have been using the curve fitting toolbox's custom equation capabilities to fit data to my user defined equation. Of course these equations are of the form:

eqn=f(x,a,b,c) where x is the independent variable, and a,b,c are the fitted parameters.

Ok, that's pretty simple, but now I want to define my custom equation including analysis by a TriScatteredInterp Object, let's call it Interp_Obj. (although, this question pertains to any object that one would want to put in the custom equation.)

I want my equation to now look like: eqn=Interp_Object(f(x,a,b),g(x,c)) The independent variable is still x, and the fitting variables are still a,b,c, but the calculation of eqn is now simply performed using an object call.

I tried passing the name of my object via the 'problem' option, but that doesn't seem to work. Anyone have any ideas?

Answer 1

[Kevin Holst]

I don't think TriScatteredInterp is what you're wanting to use there. TriScatteredInterp is used similar to griddata, in that you give it a lot of scattered points and then ask it to interpolate to find out what value is at point X,Y,Z.

Unfortunately I don't know what you should use for that situation, so maybe someone else will chime in here.