If you have it in memory then just e.g.
A = rand(500,500,500);
figure; plot( A(:,:,33)
figure; plot( A(22,:,:)
figure; imagesc( squeeze( A(:,99,99) );
If the data is too big to load all of it into memory to plot a small part of it then
doc matfile
should help. It allows you to access data on disk as though it were in memory, using indexing just like above, but with A represented by a matfile.
