Assume I have a 4x1 cell array,A, inside each cell is a 2x5 matrix,
A={[1 1 1 1 1; 2 2 2 2 2];
[3 3 3 3 3; 4 4 4 4 4];
[5 5 5 5 5; 6 6 6 6 6];
[7 7 7 7 7; 8 8 8 8 8]}
what I want is to add a constant,let's say 100, to the 4th column of matrix for each cell to make B. For example
B={[ 1 1 1 101 1; 2 2 2 102 2];
[3 3 3 103 3; 4 4 4 104 4];
[5 5 5 105 5; 6 6 6 106 6];
[7 7 7 107 7; 8 8 8 108 8]}
What is the best way to do it?
I can get the addition result by using
B=cellfun(@(x) x(:,4)+100,A,'uni',0)
but have difficult to get B. Any help is greatly appreciated.
If you can guarantee that the matrix in cell in A is of the same dimensions (in your case, a 2x5 matrix), you can concatenate all matrices vertically:
B = cat(1, A{:});
then add 100 to the fourth column:
B(:, 4) = B(:, 4) + 100;
and then convert back it back to a cell array:
B = mat2cell(B, size(A{1}, 1) * ones(size(A)), size(A{1}, 2));
In this case consider representing the data as a three-dimensional matrix instead of a cell array. It would be much easier to manipulate.
In the general case, you would employ a for loop:
B = A;
for k = 1:numel(A)
B{k}(:, 4) = B{k}(:, 4) + 100;
end