Given a charatcer table record, I'd like to calculate the size of the
subgroup generated by a list of classes. Is this possible in GAP?
Actually I am not sure if this is theoretically possible, so perhaps
I should ask if the character table record (and in particular the power
maps) contain enough information to do this. Thanks.

Jacob Hirbawi <JcbHrb@CERF.net>

I'd guess that all the information needed is already in.
There is a function ClassMultCoeffCharTable(tbl,c1,c2,c3),
it returns the number of pairs (x,y) of elements of G
such that x\in c1, y\in c2, and xy is a fixed element
of c3.

So one can start with a given subset of classes and repeatedly
apply this function to find all the classes which get involved.
Then it remains to add up their sizes.

( Since it appears to be practically possible, it should also
be possible theoretically. :-) )

Regards,
Dima Pasechnik,
pasec@can.nl
dima@maths.uwa.edu.au