[GAP Forum] Converting lists of groups into direct products

Nick.Gill Nick.Gill at open.ac.uk
Fri Jun 21 16:31:50 BST 2013


Hello GAP-forum,

I'm new to the group, so not familiar with the protocol. Forgive me if I'm asking a stupid question and/or omitting vital information...

I have a list of groups - grouplist - and two lists of elements - elist1, elist2 - such that, for each index i, elist1[i] and elist2[i] are members of grouplist[i].

Now I use the command
D:= DirectProduct(grouplist)
Here's what I want to do next:
(1) I would like to convert elist1, elist2 into a format where GAP recognises them as members of D, i.e. I want to convert them from being lists into tuples.
(2) Find the subgroup of D generated by elist1 and elist2.

It's (1) that I'm having trouble with - how do I do it?!

The groups in grouplist, incidentally, are either permutation groups or quotients of the free group on 2 letters. I don't know if this fact is important...

All replies appreciated. Warning: I'm extremely ignorant at GAP so have limited capacity to understand complicated responses!

Nick

-- 
The Open University is incorporated by Royal Charter (RC 000391), an exempt charity in England & Wales and a charity registered in Scotland (SC 038302).




More information about the Forum mailing list