# HG changeset patch
# User Anders Claesson <anders@ru.is>
# Date 1248543177 0
# Node ID 7ee14d081bde6b08274996ed9251c8746fde4462
# Parent 78ea5b9e2f85b9befff57c38d28fb2266f8250e9
Improve running time of inverse method
diff -r 78ea5b9e2f85 -r 7ee14d081bde sage/combinat/permutation.py
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890 | 890 | sage: Permutation([2, 4, 1, 5, 3]).inverse() |
891 | 891 | [3, 1, 5, 2, 4] |
892 | 892 | """ |
893 | | return Permutation([self.index(i+1)+1 for i in range(len(self))]) |
| 893 | w = range(len(self)) |
| 894 | for i,j in enumerate(self): |
| 895 | w[j-1] = i+1 |
| 896 | return Permutation(w) |
894 | 897 | |
895 | 898 | def _icondition(self, i): |
896 | 899 | """ |