Fitting 3D Graph

Dear Rootters,

Is there any possibility to fit a function of three variables F(x,y,z) ??

In the case of two-variables { F(x,y) }, I use TGraph2DErrors *AAA = new TGraph2DErrors();…e.t.c.

Is there a kind of extension of TGraph2D to TGraph3D or something similar?

My function is the reduced cross section, which depends upon three variables \sigma(x,Q^2,y) with the error d\sigma

Thank you,


Additional question:

The function I want to fit is an integral over three-dim intedgrand.

F(x,y,z) = Int[ f(r,s,t;,x,y,z) ]

What I do: first I calculate the integral F(x,y,z), and than I fit F to the data points.

If I’m not mistaken (I’ve seen it in some posts), there is a possibility to combine the fit and the integral calculation (to reduce the running time).

If it is correct, I’ll appreciate any links or examples on this subject.