Re: Transforming a list
- To: mathgroup at smc.vnet.net
- Subject: [mg103150] Re: [mg103108] Transforming a list
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Wed, 9 Sep 2009 04:44:31 -0400 (EDT)
- Reply-to: hanlonr at cox.net
lst = {{c, e, g}, {d, f}, {e, g}, {f}, {g}, {}};
Transpose[PadRight[lst]] /. 0 -> Sequence[]
{{c,d,e,f,g},{e,f,g},{g}}
Bob Hanlon
---- Don <donabc at comcast.net> wrote:
=============
I am given: lst = {{c, e, g}, {d, f}, {e, g}, {f}, {g}, {}}
I want to form a list of sublists where the first sublist consists of the first elements
from each sublist of lst, the second sublist the second elements from each of the sublists of lst etc.
The final outcome should be:
{{c, d, e, f, g}, {e, f, g}, {g}}
I can do this by first padding the sublists of lst (to make them the same length)and then using Transpose. But how to get rid of the trailings 0's?
For example:
newLst = Map[PadRight[#, Length[lst[[1]]]] &, lst]
Transpose[newLst]
which produces:
{{c, d, e, f, g, 0}, {e, f, g, 0, 0, 0}, {g, 0, 0, 0, 0, 0}}
Is there a better way to end up with
{{c, d, e, f, g}, {e, f, g}, {g}}
Thank you.