adding matrices inside cell array

how does one add all of the matrices stores in a cell array?

[Oleg Komarov]

Be more specific, what do you intend by add the matrices? (take the sum of each single matrix, sum elementwise all the matrixes, all the single matrix sums are added together?

Answer 1

[vish]

a={[1,2;3,4],[1,2;3,4];[1,2;3,4],[1,2;3,4]}
a{1}+a{2}+a{3}+a{4}

If there are many elements, use two for loops and run all the positions one by one using the equation c=a{i,j} + a{i+1,j+1}.

Answer 2

[Oleg Komarov]

An example:

% Create dummy input
c = {[1 2; 3 4], [3 3; 1 1]}
c = 
    [2x2 double]    [2x2 double]

% Elementwise sum across matrices (only if ALL matrices have same size)
sum(cat(3,c{:}),3)
ans =
     4     5
     4     5

% Total sum of each matrix
cellfun(@(x)sum(x(:)),c,'un',0)
ans = 
    [10]    [8]

% Grand sum
c = cellfun(@(x) x(:),c,'un',0);
sum(cat(1,c{:}))
ans =
    18

Oleg

[Mariacarla Memeo]

Excuse me Oleg,

can you explain your solution for the first case(sum of each element of matrices), because I have to sum 72 matrices [25x25] placed in a cell array [72x1] and I've no idea to how set your solution in my example. Please.