[GAP Forum] Help_GAP-groups

[Alexander Hulpke]

Dear Forum,

On Jan 16, 2011, at 1/16/11 4:49, Junio Moreira wrote:

> I'm always needing to learn more about the GAP-groups. Can anyone help me on the following question? Question: I have a list of 500 sublist where each sublist consists of six groups. Is there a command to display or renumber only those sublists with trivial intersection? Is there a function in GAP can solve this?

If the entries in the sublist are algebraic structures (i.e. ``trivial'' means order 1), you could use

Filtered(list,sub->Size(Intersection(sub))=1);

to give you a sublist of the desired entries.(replace 1 by 0 if trivial means empty)

 If instead you wanted the index numbers in your original list, you could use

Filtered([1..Length(list)],n->Size(Intersection(list[n]))=1);

Best,

   Alexander Hulpke



-- Colorado State University, Department of Mathematics,
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