delete the rows will all zeros in multi-dimensional matrix

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Dear all,
Let say I have a matrix M of size 6 x 3 x 3. And on each channel there are some zero rows (note that zero rows are evenly present in all channels). How can I remove the rows with all zeros.
For example,
M(:,:,1) =
422 397 553
0 0 0
0 0 0
476 494 520
0 0 0
0 0 0
M(:,:,2) =
0 0 0
384 494 504
0 0 0
0 0 0
385 446 474
0 0 0
M(:,:,3) =
0 0 0
0 0 0
1194 1176 1295
0 0 0
0 0 0
1202 1141 1295
  3 Comments
Azzi Abdelmalek
Azzi Abdelmalek on 16 Sep 2012
Edited: Azzi Abdelmalek on 16 Sep 2012
If you remove certain rows, your chanels will have different sizes, then you should use cell array. In this case they have the same size, but not in general

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Accepted Answer

Andrei Bobrov
Andrei Bobrov on 16 Sep 2012
Edited: Andrei Bobrov on 16 Sep 2012
out = reshape(M(bsxfun(@times,any(M,2),ones(1,size(M,2)))>0),[],size(M,2),size(M,3));
or only for your example
reshape(M(M>0),[],size(M,2),size(M,3))

More Answers (1)

Azzi Abdelmalek
Azzi Abdelmalek on 16 Sep 2012
Edited: Azzi Abdelmalek on 16 Sep 2012
for k=1:size(M,3)
A=M(:,:,k)
A(find(sum(A,2)==0),:)=[]
res{k} = num2cell(A)
end
res{:}

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