Deflation
A dimensional slicing Sij of the N-grid Q is the operation of taking sections via members of a dimension Di and tiling them within the dimension Dj using member ordering of Di. The result is a (N-1)-grid.
In other words, we create a virtual dimension VijÌD{ij}consisting of pairs (m1, m2), m1 Î Di, , m2 Î Dj ordered first by m1 and then by m2, and take