Creating a matrix within a matrix

2013 2 21
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I'm having trouble on how to create an MxN matrix will all zeros and in that MxN matrix I want the the first column, first row, last row, and last column to be zeros while the rest of the matrix is all different numbers, with possible values as 0 zeros as well. An example is below,
0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 1 1 0 1 0 1 1 1 1 1 0 0 0
0 0 1 1 0 1 0 0 0 1 1 1 1 0
0 1 0 1 1 1 1 0 1 0 1 0 1 0
0 1 0 0 1 1 1 1 1 1 1 1 1 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0
Really the only values that the middle section can have is one or zero but the outsides have to all be zeros.

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José-Luis
José-Luis 2013-2-21
编辑：José-Luis 2013-2-21
Is this homework? What have you tried so far? This could be achieved with logical indexing or a function from the image processing toolbox.
Jakub
Jakub 2013-2-21
Well the first step I tried was doing zeros(M,1,1) and then (zeros(1,N,1) and got stuck with that because that only provided me with the first row and column. Next I tried doing a zeros(M,N) but that leaves me with a MxN zero matrix.
Jakub
Jakub 2013-2-21
It's actually part of my Thesis however I have no prior computer programing background and my adviser took the week off ~_~

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Matt J
Matt J 2013-2-21
编辑：Matt J 2013-2-21

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If you're saying you have a given matrix A and want to set the edges to zero,
A([1,end],[1,end])=0;

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Jakub
Jakub 2013-2-21
Alright I understand that, thank you. One last question would be how do I randomly pick values either 0 or 1 inside the submatrix I want. Meaning I leave the outside all zeros but generate possible 1 or 0 on the inside.
Matt J
Matt J 2013-2-21
Use randi() to generate random zeros and ones everywhere. Then use the code I showed you to set the boundaries to zero.

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