comparison_cellDivision: Split a reference scan into a grid of cells
Description
Split a reference scan into a grid of cells
Value
A tibble containing a prod(numCells) number of rows. Each row contains
a single cell's index of the form (row #, col #) and an x3p object
containing the breech face scan of that cell.
Arguments
x3p
an x3p object containing a breech face scan
numCells
a vector of two numbers representing the number of cells along
the row and column dimensions into which the x3p is partitioned