use sets instead of lists in the orbit decomposition#41641
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vbraun merged 2 commits intosagemath:developfrom Feb 25, 2026
Merged
use sets instead of lists in the orbit decomposition#41641vbraun merged 2 commits intosagemath:developfrom
vbraun merged 2 commits intosagemath:developfrom
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Documentation preview for this PR (built with commit 234da7a; changes) is ready! 🎉 |
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Several doctests must be updated. |
vbraun
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sagemathgh-41641: use sets instead of lists in the orbit decomposition Currently, `cycles` and `orbits` do the orbit decomposition by picking an element, creating the orbit and then removing newly created elements from the list of all elements. However, removing an element from a list takes O(n) operations. Turning the list into a set makes some computations possible that would otherwise be quite impossible. Unfortunately, this means that the (cyclic) ordering of the cycles may change, because we do not control anymore which element is picked first. However, this is only a doctest problem. URL: sagemath#41641 Reported by: Martin Rubey Reviewer(s): David Coudert
vbraun
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Feb 20, 2026
sagemathgh-41641: use sets instead of lists in the orbit decomposition Currently, `cycles` and `orbits` do the orbit decomposition by picking an element, creating the orbit and then removing newly created elements from the list of all elements. However, removing an element from a list takes O(n) operations. Turning the list into a set makes some computations possible that would otherwise be quite impossible. Unfortunately, this means that the (cyclic) ordering of the cycles may change, because we do not control anymore which element is picked first. However, this is only a doctest problem. URL: sagemath#41641 Reported by: Martin Rubey Reviewer(s): David Coudert
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Currently,
cyclesandorbitsdo the orbit decomposition by picking an element, creating the orbit and then removing newly created elements from the list of all elements.However, removing an element from a list takes O(n) operations. Turning the list into a set makes some computations possible that would otherwise be quite impossible.
Unfortunately, this means that the (cyclic) ordering of the cycles may change, because we do not control anymore which element is picked first. However, this is only a doctest problem.