Order a sudoku.
Y = sudoku_order ( X )
a 9x9 matrix
a permuted 9x9 matrix.
Order the rows and columns of a sudoku so that the first block is
1 2 3
4 5 6
7 8 9
by using relabelling.
X = [ 6 7 3 1 5 8 2 4 9 4 1 8 2 6 9 5 3 7 9 2 5 4 3 7 8 6 1 .. 5 8 2 3 4 1 7 9 6 3 4 7 6 9 2 1 8 5 1 9 6 7 8 5 3 2 4 .. 7 5 4 8 2 6 9 1 3 2 3 1 9 7 4 6 5 8 8 6 9 5 1 3 4 7 2 ]; Y = sudoku_order ( X )