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Topic: help : how to reverse 2-D lookup table ?
Replies: 10   Last Post: Oct 30, 2013 5:54 AM

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 meng yan Posts: 5 Registered: 1/29/10
Re: help : how to reverse 2-D lookup table ?
Posted: Jan 29, 2010 7:56 PM

"John D'Errico" <woodchips@rochester.rr.com> wrote in message <hjuipn\$bmr\$1@fred.mathworks.com>...
> "meng yan" <anoucxy@163.com> wrote in message <hju7lf\$e34\$1@fred.mathworks.com>...
> >
> >
> > I am trying to reverse a 2D lookup table, i.e.I have T=T(a,b), I need to figure out
> > a=a(T,b). Anybody ever tried this before? Any ideas?
> > i.e.a=[1 2 3];b=[3 4 5];T=[1 3 4;4 6 5;2 7 6];
> > how could I get a as a=[3X3],b=[1X3],T=[1X3]?
> > Thanks!

>
> Has anyone ever "tried it before"?
>
> Why do I need to have tried something that is not
> possible in general, or if possible, is trivial to do?
>
> Depending upon the shape of the function T(a,b),
> there may be multiple solutions, so this will not
> be possible. Even if it is possible because of a
> strictly monotonic response, then there may be
> only a limited set of solutions for certain values of
> T. But for those values of T such the a solution
> exists, it will be trivial to compute. Simply fix
> the value of b, and interpolate. WTP?
>
> John

May be should use others means, the datas of T=T(a,b) are got by inner compute of matlab using Finit Element Analysis ,so I think it cann't simplly get a(a=a(T,b)), but there must have a means to do that . I aways try to use matlab's data process to achieve it ,but all have failed. Who have a good idears ?
meng yan

Date Subject Author
1/29/10 meng yan
1/29/10 John D'Errico
1/29/10 meng yan
1/29/10 John D'Errico
1/29/10 meng yan
1/29/10 ImageAnalyst
1/30/10 meng yan
1/30/10 ImageAnalyst
1/31/10 meng yan
1/31/10 ImageAnalyst
10/30/13 Virginia