# HG changeset patch
# User Rob Beezer <beezer@ups.edu>
# Date 1299784522 28800
# Node ID 25aa3b3919010583fa0ce820b86d8a3f9495d046
# Parent 8438b7c20d79c02a2ece3e1c3f7224a772ff8f07
10911: inverse method for permutation group elements
diff -r 8438b7c20d79 -r 25aa3b391901 sage/groups/perm_gps/permgroup_element.pyx
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744 | 744 | order = Integer(order_c) |
745 | 745 | sage_free(seen) |
746 | 746 | return int(order_c) if order is None else order |
| 747 | |
| 748 | def inverse(self): |
| 749 | r""" |
| 750 | Returns the inverse permutation. |
| 751 | |
| 752 | OUTPUT: |
| 753 | |
| 754 | For an element of a permutation group, this method returns the inverse |
| 755 | element, which is both the inverse function and the inverse as an |
| 756 | element of a group. |
| 757 | |
| 758 | EXAMPLES:: |
| 759 | |
| 760 | sage: s = PermutationGroupElement("(1,2,3)(4,5)") |
| 761 | sage: s.inverse() |
| 762 | (1,3,2)(4,5) |
| 763 | |
| 764 | sage: A = AlternatingGroup(4) |
| 765 | sage: t = A("(1,2,3)") |
| 766 | sage: t.inverse() |
| 767 | (1,3,2) |
| 768 | |
| 769 | There are several ways (syntactically) to get an inverse |
| 770 | of a permutation group element. :: |
| 771 | |
| 772 | sage: s = PermutationGroupElement("(1,2,3,4)(6,7,8)") |
| 773 | sage: s.inverse() == s^-1 |
| 774 | True |
| 775 | sage: s.inverse() == ~s |
| 776 | True |
| 777 | """ |
| 778 | return ~self |
747 | 779 | |
748 | 780 | def sign(self): |
749 | 781 | """ |