While thinking of parallelising this (@raemarina @IrynaRaievska more tomorrow), noticed that the same Union(V7[w],cc) is calculated here repeatedly three times:
One should only compute it once after Size(cc)=r1 check. It calculates a Union of a semigroup with a list of endomorphisms, which may be expensive.
OTOH, if the semigroup is given by a generating set, which is smaller than its order, we could use SubsemigroupNC(Em,Union(GeneratorsOfSemigroup(V7[w]),cc)) there (and still reuse the result of Union(V7[w],cc) when adding it to Y[j].
While thinking of parallelising this (@raemarina @IrynaRaievska more tomorrow), noticed that the same
Union(V7[w],cc)is calculated here repeatedly three times:https://github.com/alex-konovalov/LocalNRconstruction/blob/e296402055a55b0a8b39b383867fadc491d0f1c0/Test125/End125_comb_new.g#L60-L62
One should only compute it once after
Size(cc)=r1check. It calculates a Union of a semigroup with a list of endomorphisms, which may be expensive.OTOH, if the semigroup is given by a generating set, which is smaller than its order, we could use
SubsemigroupNC(Em,Union(GeneratorsOfSemigroup(V7[w]),cc))there (and still reuse the result ofUnion(V7[w],cc)when adding it toY[j].