transpositions. One of these cycles is . To perform the maximality test, its first and (1, 2) second rows are compared (Figure ). In this example, the permutation is an automorphism of the first row since it maps the (1, 2) row to itself in the adjacency matrix. Then this permutation is added to the automorphisms list. However, in the case where a mapping with a cycle does not map the row to itself, a canonical permutation is needed. Same as matrix A, for an initial matrix B (Figure ) with its initial partition }, the refined partition , there are 5 cycle