Repeating matrix in matlab [duplicate]

Question

I have a square matrix say n by n; I want to expand this matrix to n^2 by n^2 such that values in the position are repeated. e.g A matrix is

2 3
5 6

I want to generate matrix B such that

2 2 3 3
2 2 3 3
5 5 6 6
5 5 6 6

How can this be done in matlab? And need to be generalized for any square matrix

Additional question: If I want to duplicate like following
2 3 2 3
5 6 5 6
2 3 2 3
5 6 5 6

How this can be archived ?

OmG · Accepted Answer · 2017-09-04 19:15:50Z

3

You can do it using Kronecker tensor product:

B = kron(A,ones(n));

answered Sep 4, 2017 at 19:15

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1 Comment

kron is the best. I would add B=kron(ones(n),A) for the second question.

Luis Mendo · Accepted Answer · 2017-09-04 19:23:46Z

Let the data be

M = [2 3; 5 6]; % initial matrix v = 2; % vertical repetition factor h = 3; % horizontal repetition factor

In addition to using kron as shown by @Omg's answer, you can do it using just indexing:

result = M(ceil(1/v:1/v:end), ceil(1/h:1/h:end));

Or, in recent Matlab versions, you can use repelem:

result = repelem(M, v, h);

Either of the above gives

result = 2 2 2 3 3 3 2 2 2 3 3 3 5 5 5 6 6 6 5 5 5 6 6 6

Additional question: If I want to duplicate like following 2 3 2 3 <br/> 5 6 5 6 <br/> 2 3 2 3 <br/> 5 6 5 6 <br/> How this can be archived ?