cells: How to take Mean over same-indexed elements across Cells?

I have a cell array of 53 different (40,000 x 2000) sparse matrices. I need to take the mean over the third dimension, so that for example element (2,5) is averaged across the 53 cells. This should yield a single (33,000 x 2016) output. I think there ought to be a way to do this with cellfun(), but I am not able to write a function that works across cells on the same within-cell indices.

Answer 1

[Andrei Bobrov]

A = arrayfun(@(x)randi(20,5 ,9),(1:4)','un',0); % your cell array

out = mean(cat(3,A{:}),3);