RE: position lists
- To: mathgroup at smc.vnet.net
- Subject: [mg68697] RE: [mg68688] position lists
- From: "David Park" <djmp at earthlink.net>
- Date: Thu, 17 Aug 2006 04:17:56 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Igor,
What's the problem? It seems that all you have to do is Flatten the inner
lists.
a = {1, 1, 2, 2, 1, 4};
Flatten@Position[a, #1] & /@ Range[4]
{{1, 2, 5}, {3, 4}, {}, {6}}
I don't see much that is simpler.
David Park
djmp at earthlink.net
http://home.earthlink.net/~djmp/
From: rych [mailto:rychphd at gmail.com]
To: mathgroup at smc.vnet.net
have
In: a = {1, 1, 2, 2, 1, 4}
want
{{1, 2, 5}, {3, 4}, {0}, {6}};
more effectively than just
In: Position[a, #] & /@ Range[4]
Out: {{{1}, {2}, {5}}, {{3}, {4}}, {}, {{6}}}
Ideas? Known one-liners?
Thanks
Igor