By default, the column index that corresponds to a given orbital pair (and vice versa) is found with a dictionary. Since APG and APsetG have specific patterns for the orbital pairs used, the column index is found using a formula instead, which should be slightly more efficient.
By default, the column index that corresponds to a given orbital pair (and vice versa) is found with a dictionary. Since APG and APsetG have specific patterns for the orbital pairs used, the column index is found using a formula instead, which should be slightly more efficient.