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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

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

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!

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