
Re: help : how to reverse 2D lookup table ?
Posted:
Jan 29, 2010 7:03 AM


"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

