Is there a way to find number of blocks in a matrix?

I have a matrix that has 5 blocks along the diagonal and two consecutive blocks overlap in one diagonal element.

How can I compute the number of blocks in MATLAB?

[KSSV]

Give us an example.

[Omar B.]

As an example:

A=[1 2 0 0 0 0 0 0 0;3 4 5 6 0 0 0 0 0; 0 7 8 9 0 0 0 0 0; 0 1 2 3 4 5 0 0 0;0 0 0 1 2 3 0 0 0;0 0 0 1 2 3 4 5 0;0 0 0 0 0 1 2 3 0;0 0 0 0 0 1 2 3 4; 0 0 0 0 0 0 0 1 2]

How can I compute the number of blocks in MATLAB?

[Joseph Cheng]

can you explain what you mean by a block?

Answer 1

[Stephen23]

Assuming that the blocks do not contain zeros:

A = [1,2,0,0,0,0,0,0,0;3,4,5,6,0,0,0,0,0;0,7,8,9,0,0,0,0,0;0,1,2,3,4,5,0,0,0;0,0,0,1,2,3,0,0,0;0,0,0,1,2,3,4,5,0;0,0,0,0,0,1,2,3,0;0,0,0,0,0,1,2,3,4;0,0,0,0,0,0,0,1,2]

A = 9×9

1 2 0 0 0 0 0 0 0 3 4 5 6 0 0 0 0 0 0 7 8 9 0 0 0 0 0 0 1 2 3 4 5 0 0 0 0 0 0 1 2 3 0 0 0 0 0 0 1 2 3 4 5 0 0 0 0 0 0 1 2 3 0 0 0 0 0 0 1 2 3 4 0 0 0 0 0 0 0 1 2

[R,~] = find(diff(~A,1,1)>0);
N = 1+numel(unique(R))

N = 5

If the blocks can contain zeros, then you will probably need to use some pattern matching.

[Omar B.]

Thank you so much.