Efficient slicing of cell array?

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EGTork
EGTork 2015-3-20
编辑： EGTork 2015-3-20
I have a cell array of the form:
c =
[1x100 double]
[2x150 double]
[3x200 double]
And I would like to create a 6x50 matrix consisting of all rows and the first 50 columns of each constituent matrix. Is there an efficient way to do this?

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Andrei Bobrov
Andrei Bobrov 2015-3-20
variant
cell2mat(cellfun(@(x)x(:,1:50),C,'un',0));
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EGTork
EGTork 2015-3-20
编辑：EGTork 2015-3-20
Thanks, Andrei. For reference, I compared this cell array approach against directly indexing a matrix to create a submatrix. The cell array solution took about 5X as long, which is not bad considering the extra flexibility provided by cell arrays.
Specifically, I took a cell array containing five 10x100,000 matrices, and used your approach to generate a 50x75,000 submatrix. I compared this to directly indexing into a 50x100,000 matrix to create a 50x75,000 submatrix. For matrices of this size, there was a 5X penalty for using cell arrays instead of a matrix. For smaller matrices, the penalty was somewhat higher (~10X).

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