Re: match 1, replace 2
- To: mathgroup at smc.vnet.net
- Subject: [mg56263] Re: [mg56199] match 1, replace 2
- From: "Fred Simons" <f.h.simons at tue.nl>
- Date: Wed, 20 Apr 2005 05:32:08 -0400 (EDT)
- References: <200504190854.EAA02514@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Trevor,
No doubt you will see many solutions. Here there are two of them.
This one works for any list of lists:
With[{z = Last /@ ls},
MapThread[Append[#1,
#2] & ,
{Replace[Most /@ ls,
n_ :> Sequence[100 + n,
-1], {2}], z}]]
And here is one for a list of lists of integers:
ls /. n_Integer :> Sequence[
100 + n, -1] /.
{a___, b_, c_Integer} :>
{a, b + c - 99}
Regards,
Fred Simons
Eindhoven University of Technology
----- Original Message -----
From: "Trevor Baca" <trevorbaca at gmail.com>
To: mathgroup at smc.vnet.net
Subject: [mg56263] [mg56199] match 1, replace 2
> hi mathgroup,
>
> what rule takes
>
> ls = {{1, 2, 3}, {4, 5}, {6, 7, 8, 9}}
>
> to
>
> {{101, -1, 102, -1, 3}, {104, -1, 5}, {106, -1, 107, -1, 108, -1,
> 9}}
>
> ie, matches all integers but the last in each list and then replaces
> each matched integer n with the 2-element sequence Sequence[100 + n,
> -1]?
>
> trevor.
>
- References:
- match 1, replace 2
- From: "Trevor Baca" <trevorbaca@gmail.com>
- match 1, replace 2