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Topic: Bivariate Pchip
Replies: 9   Last Post: Jan 19, 2013 6:14 AM

 Messages: [ Previous | Next ]
 John D'Errico Posts: 9,130 Registered: 12/7/04
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 2-dimensional 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 2-d pchip implemented for MATLAB that I know of.
> >
> > 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 2-d 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 2-d. If someone has the
reference I have described as a pdf, I'd see about an
implementation.

John

Date Subject Author
1/16/13 samar
1/16/13 John D'Errico
1/16/13 samar
1/18/13 John D'Errico
1/17/13 Bruno Luong
1/17/13 Bruno Luong
1/18/13 John D'Errico
1/18/13 Bruno Luong
1/18/13 John D'Errico
1/19/13 Bruno Luong