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Optimizing Magma Code

Subsections

PowerGroup

If the user is working with enumerated sets of pc-groups that are all subgroups of a common over-group G, then the following optimization is strongly recommended. Define the set to have the universe PowerGroup(G). For any subgroup H of G, we can find a canonical form for the generators of H. This allows us to have a very good hashing function for the subgroups.


Example GrpPC_PowerGroupTwo (H59E36)

The following example illustrates the optimization.

> G := ExtraSpecialGroup( GrpPC, 3, 3 );
> P := PowerGroup(G);
> time s1 := {  P | sub< G | Random(G), Random(G) > : x in { 1..500 }  };
Time: 1.140
> time s2 := { Parent(G) | sub< G | Random(G), Random(G) > : x in { 1..500 }  }; 
Time: 9.769
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