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Re: Bivariate Pchip
Posted:
Jan 18, 2013 8:59 AM


"samar" wrote in message <kd7th9$aac$1@newscl01ah.mathworks.com>... > "John D'Errico" <woodchips@rochester.rr.com> wrote in message <kd7l8o$hbg$1@newscl01ah.mathworks.com>... > > "samar" wrote in message <kd6sdp$qnk$1@newscl01ah.mathworks.com>... > > > Hi all, > > > > > > I would like to use Pchip function to interpolate my 2dimensional data set. > > > > > > I'm actually using spline interpolation (with csapi function) but it doesn't work well. > > > I think that Pchip will be better for my data set but I have no idea how to use it with 2 variables: x1 (n values) and x2 (m values) are my variables and V=f(X1,X2) is the n*m matrix containning all values taken by f for each couple (x1,x2) > > > > > > The second question can we have the result of pchip in PPFORM? > > > > > > Thank you very much for you help! > > > > 1. pchip DOES return a ppform. > > > > 2. There is no 2d pchip implemented for MATLAB that I know of. > > > > John > > Thank you very much for your answer John > Do you have an idea whether there is another similar function in 2d? > As I said previously I'm using csapi function now and it doesn't perform well with my 2d data set! > > Than you
No, as far as I know, there is no tool available in 2d for this. I'd be willing to write one, as there are others who have asked for it, but I lack the paper that describes the fix for pchip so it will work in 2d. If someone has the reference I have described as a pdf, I'd see about an implementation.
John



