MATLAB: 3D approximation with spline

Question

Hi everybody, I want to approximate a 3D function ( 3 state variables with a large set of points for each one)! Does anyone knows how to do it? I used to use Csapi function for a two-dimensional functions

Thank you

Answer 1

Have you checked out the curve fitting toolbox, specifically the “fit” function?

http://www.mathworks.com/help/curvefit/fit.html

Here you can fit 3 dimensional data to a fit type of your choosing. One of the fit types include the ‘smoothingspline’ option which attempts to connect the data using a smoothing spline fit.

Alternatively you could run the cftool app with your data in the workspace and select the type of fit you would like via the dropdowns.

http://www.mathworks.com/help/curvefit/cftool.html

You might also want to take a look at this page from MATLAB’s documentation that talks about constructing spline curves in 2D and 3D.

http://www.mathworks.com/help/curvefit/examples/constructing-spline-curves-in-2d-and-3d.html