adding a sequence of matrices

How can I add G number of matrices? I mean I need to sum G number of matrices. For example: G=3, so, x1=[1 2 3 4; 2 3 4 5], x2=[1 1 2 2; 2 3 3 4], x3=[4 5 6 7; 1 2 3 4].

I need x1+x2+x3

It seems very simple, but if G varies, say, in every run of a simulation, I need something general, like x1+x2+.....+xG

[Andrei Bobrov]

A simple example in numerical form

Answer 1

[the cyclist]

One way:

Use cell arrays to define your individual arrays.

x{1}=[1 2 3 4; 2 3 4 5];
x{2}=[1 1 2 2; 2 3 3 4];
x{3}=[4 5 6 7; 1 2 3 4].
% ...
x{G} = [1 2 1 2; 8 8 8 8];

Then sum them with a loop

Y = x{1};
for gi = 1:G
    Y = Y + x{gi};
end

[Andrei Bobrov]

sum(cat(3,x{:}),3)