I have a cell A(361,1) which contains 361 x 3D matrices. The first and second dimensions of matrices are same but the length of third dimension varies.
So the cell A looks like:
A={(464x201x31);(464x201x28);(464x201x31);(464x201x30)....}
I would like to get back the matrices from this cell by loop. I tried the following solution:
for i=1:361;
M(i)=cell2mat(A(i));
end
But I got the following error:
Subscripted assignment dimension mismatch.
1. If you want to access each 3D array separately from the cell array, you could always use A{i} to get each 3D matrix.
Example:
%// Here i have taken example cell array of 1D matrix
%// but it holds good for any dimensions
A = {[1,2,3], [1,2,3,4,5], [1,2,3,4,5,6]};
>> A{1}
ans =
1 2 3
2. Instead, if you want to concatenate all those 3D matrices into a single three dimensional matrix, here is one approach
out = cell2mat(permute(A,[1 3 2])); %// assuming A is 1x361 from your example
or
out = cell2mat(permute(A,[3 2 1])); %// assuming A is 361x1
3. Instead if you wanna NaN pad them to obtain 4D matrix,
maxSize = max(cellfun(@(x) size(x,3),A));
f = @(x) cat(3, x, nan(size(x,1),size(x,2),maxSize-size(x,3)));
out = cellfun(f,A,'UniformOutput',false);
out = cat(4,out{:});
Sample run:
>> A
A =
[3x4x2 double] [3x4x3 double] [3x4x4 double]
>> size(out)
ans =
3 4 4 3
%// note the first 3 size. It took the max size of the 3D matrices. i.e 3x4x4
%// Size of 4th dimension is equal to the no. of 3D matrices
You could access each 3D matrix by out(:,:,:,i)