Easiest would be to create them as planes in a 3d array instead of as multiple variables. Then would be
M=mean(X,3); % 2D array of means along dimension 3
If you already have the two variables, then
M=(A+B)/2; % explicit operation for two arrays
In more general terms the syntax would be
M=mean(cat(3,A,B)); % same result for two 2D arrays, A, B
except have to string all the arrays together in the catenation operation.
All in all, making related data that is to be operated on together separate variables is the harder way to approach things.
