Find subvector/submatrix within matrix (with place holder)

Hello,

I want to find specific patterns, which are not connected in a matrix.

For example.

The complete vector is a = [1 2 3 4 5 6 8 10]

and now I want to find b = [1 2 X 4], X should be some place holder, I don't care about the value there.

This would be the 1d case, but I'm also interested in the 2d case.

Does anyone have a good idea for the implementation or already code fragments?

Thanks

Answer 1

[Image Analyst]

The wildcard makes it tricky. Probably strfind() or regexp(). It will be very cryptic, but someone (Andrei, etc.) will know how.

Or you can use a brute force, but easy-to-understand way of scanning element by element looking for a match. In 2-D you can use nlfilter(), in the Image Processing Toolbox, to help.