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From: Ross <fed.rossi@gmail.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: interp3
Date: Tue, 7 Apr 2009 21:38:16 -0700 (PDT)
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Thanks John!
R


On Apr 7, 11:30=A0pm, "John D'Errico" <woodch...@rochester.rr.com>
wrote:
> Ross <fed.ro...@gmail.com> wrote in message <48891dbe-8e0b-410e-9cf4-4dda=
5e08f...@v28g2000vbb.googlegroups.com>...
> > Hi everyone,
>
> > I am not sure if matlab has a built-in function for this.
>
> > Instead of using interp3 to linearly interpolate a three-dimensional
> > function V as follows,
>
> > VI =3D interp3(X,Y,Z,V,X,Y,ZI),
>
> > I would like to retrieve the value of ZI given that VI,X,Y are known.
>
> When you fix the value of X and Y, this reduces
> the problem to a 1-d inverse problem. I would
> convert it to a simple problem V(Z) - V0 =3D 0, for
> the given value of V. Now it is just a question of
> finding the zero crossings. If you do not know
> how to do that, then look for "intersections" on
> the file exchange (by Doug Schwarz.)
>
> John