On Thu, Jun 16, 2011 at 06:28, Christian K. <ckk...@hoc.net> wrote: > Hi, > > I need to do fit a 3d surface to a point cloud. This sounds like a job for 3d > orthogonal distance regression. Does anybody know of an implementation?
As eat points out, scipy.odr should do the job nicely. You should read at least part of the ODRPACK User's Guide in addition to the scipy docs for it: http://docs.scipy.org/doc/external/odrpack_guide.pdf The FORTRAN examples there have scipy.odr translations in the unit tests: https://github.com/scipy/scipy/blob/master/scipy/odr/tests/test_odr.py Exactly what you need to do depends on the details of your problem. If your surface is of the form z=f(x,y), that's a pretty straightforward multidimensional model. If you have a closed surface, however, you will need to use an implicit model of the form f(x,y,z)=0, which may or may not be easy to formulate. The unit test for the implicit case fits a general 2D ellipse to a 2D cloud of points, as described in the User's Guide. -- Robert Kern "I have come to believe that the whole world is an enigma, a harmless enigma that is made terrible by our own mad attempt to interpret it as though it had an underlying truth." -- Umberto Eco _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion
