gap-system / gap / 10123

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travis-ci

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Commit Message

Improvements to finding permutation representations and to automorphism group computations (#3494)

ENHANCE: Improved permutation representation for factor groups

ENHANCE: Improvements to automorphism group computations

Use small layer action and (if needed) iterated maximals to find good perm
rep.  in hard cases.
Also rewrote intersection loop more efficiently and change of info printout.

Avoid forcing computation of bad representation as intermediate result

Faster/better strategies for permutation representations for automorphism
groups, both wreath and if intransitive group.

Calculation precomputes nathoms in autsr in reverse order,
as the larger quotients might help the smaller ones.
Use LR decomposition for solving iterated linear systems.
Better subgroup search.

Offer alternative to SubgroupProperty, but so far do not use it at
`SubgroupProperty` seems to behave more uniformly. Also make the
automorphism group tests not waste time in assertions on maps being
homomorphisms.

* ENHANCE: iterator wont jump at calculating lattice

Subsequent manual examples

* FIX whitespace issue in test

and protect from reliance on generator numbers.

* PERFORMANCE: Use `SmallerDegree..` with cheap option

when calling for performance improvements

* NOCODECHANGE: Trivial manual changes that arose from last example

* NOCODECHANGE: Added code coverage to satisfy coveralls test.

Run Details

363 of 415 new or added lines in 13 files covered. (87.47%)

149 existing lines in 12 files now uncovered.

287044 of 336577 relevant lines covered (85.28%)

23470585.0 hits per line