cell to matrix conversion with a slight modification

I have a 1×501 cell array(named C). Each element in the cell is a 4*4 matrix, which means I have 501 matrices of 4*4 dimensions. What I have to do is: for each matrix in the cell, all the elements in the particular matrix must be put in 1 row.

for example I have to convert

[1,2,3,4 [0,1,0,0

5,6,7,8 1,0,0,0 ..........so one upto 501 matrices

9,10,11,12 0,0,1,1

13,14,15,16] 0,0,0,1]

into

[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,

0,1,0,0,1,0,0,0,0,0,1,1,0,0,0,1

.............

........

so on upto 501 rows. ]

Help if possible.

Answer 1

[Guillaume]

Assuming that you mean a 501x16 matrix, then:

m = reshape(cat(3, yourcellarray{:}), [], numel(yourcellarray)).'

This concatenate the 501 matrices into a 4x4x501 matirx array, reshape that into a 16x501 matrix where each column is a flattened matrix and then transpose into a 501x16 matrix.

[hrushikesh kyathari]

Thanks for the reply, but I guess I didn't explain my question properly which led to miscomprehension. I editted it, could you please look into it again.

[Guillaume]

Your edit is exactly what my code does except that since matlab is column major, the matrix

[1  2  3  4
 5  6  7  8
 9  10 11 12
 13 14 15 16]

gets reshaped into

[1 5 9 13 2 6 10 14 3 7 11 15 4 8 12 16]

If the order does really matter then you ought to work with columns rather than rows as that would avoid a lot of expensive (in term of time) transpositions / permutations, but this will do:

m = reshape(permute(cat(3, yourcellarray{:}), [3, 2, 1]), numel(yourcellarray), [])

[hrushikesh kyathari]

Thanks a lot, I actually did a silly mistake as I copied your 1st answer but gave the output as my original cell .My bad, sorry for that.

The order does matter for me, I need the order to be as [1,2,3,5,6,7,9,10,11,4,8,12]

I actually don't need the last row. I would be pleased if you could help me here.

[Guillaume]

If by last row, you mean the last cell of the cell array, then just delete it before the conversion, or:

m = reshape(permute(cat(3, yourcellarray{1:end-1}), [3, 2, 1]), numel(yourcellarray)-1, [])

[hrushikesh kyathari]

no, I meant the last row of each matrix, so if a matrix is

[1 2 3 4

5 6 7 8

9 10 11 12

13 14 15 16]

I need it to be made as [1,2,3,5,6,7,9,10,11,4,8,12]. So I want to apply this to all the matrices

So this would result in final outcome as 501*12 martix.

[Guillaume]

Well, then simply remove the last 4 columns from the output

croppedm = m(:, 1:end-4);

or you can do:

m = cat(3, yourcellarray{:})
m = reshape(permute(m(1:end-1, :, :), [3, 2, 1]), numel(yourcellarray), [])