Hi John > rg = r'(\w)(?=(.)\1)' > > That would at least isolate the number, although you'd still have to get > it out of the list/tuple.
I have no idea how to do this in Python in a terse way - but I'll try ;-) In Perl, its easy. Here, the "match construct" (\w)(?=(.)\1) returns all captures in a list (a 1 a 2 a 4 b 7 c 9) because we capture 2 fields per comparision: The first is (\w), needed for backreference, the second is the dot (.), which finds the number in the center (or any- thing else). So, in perl you 'filter' by the 'grep' function on each list element: grep{ /\d/ } - this means, only numbers (\d) will pass through: $_ = 'a1a2a3Aa4a35a6b7b8c9c'; print grep{/\d/} /(\w)(?=(.)\1)/g; #prints => 1 2 4 7 9 I'll try to fiddle somthing out that works in Python too ... Regards M. -- http://mail.python.org/mailman/listinfo/python-list