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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 30, 2010 6:04 AM
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ImageAnalyst <imageanalyst@mailinator.com> wrote in message <c6c16305-02f9-4b5a-89a6-d1918f5d322a@u41g2000yqe.googlegroups.com>...
> I don't understand this: a(a=a(T,b))
> I don't know what you're trying to get.
> Are you trying to get a profile or contours or something like that?
> For example, let's say that T is a 2D array and for a certain row and
> column, T will have a value. Do you then want to find all rows and
> column where T = 42 (for example, or some other value)? Something
> like this code from the help?
>
> [X,Y,Z] = peaks(30);
> surfc(X,Y,Z)
> colormap hsv
> axis([-3 3 -3 3 -10 5])
> set(gcf, 'Position', get(0,'Screensize')); % Maximize figure.
>
> Of maybe you can simply use the find() function, like
> [rows columns] = find(T == 42)
>
> Giving us a better description of what you want will get you better
> answers.


Hi,ImageAnalyst,I'm sorry to failed to description it clearly.
the question is : I have a matrix T , two vectors a and b,size(T)=101*181,
size(a)=1*101,size(b)=181*1,so I can use 2-D lookup table blocks to got the value of T depending on the input a and b, the most important question is I don't know the relation between T with a and b,only their datas .so if I want to got the value of a , the input of 2-D lookup table block are T and b, how to achieve it? is it possible?
eg.
a=[1 2 3];b=[4 5 6];T=[1 3 5;2 4 6;3 4 5]; a and b as the inputs of lookup table ,output is the value of T, when inputs is 1 and 4,we can got T=1
what I want to do is: T and b as the inputs of lookup table ,output is the value of a,there still don't know their relation.
can you got my idears?
I'm sorry my writting english is so bad.
thanks!



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