Re: Re: how to get the longest ordered sub sequence of a
- To: mathgroup at smc.vnet.net
- Subject: [mg103231] Re: [mg103177] Re: how to get the longest ordered sub sequence of a
- From: DrMajorBob <btreat1 at austin.rr.com>
- Date: Fri, 11 Sep 2009 05:25:52 -0400 (EDT)
- References: <h87pgp$5gt$1@smc.vnet.net> <200909101117.HAA17704@smc.vnet.net>
- Reply-to: drmajorbob at yahoo.com
That's the longest CONSECUTIVE non-decreasing subsequence. Bobby On Thu, 10 Sep 2009 06:17:34 -0500, Emu <samuel.thomas.blake at gmail.com> wrote: > On Sep 9, 6:37 pm, a boy <a.dozy.... at gmail.com> wrote: >> how to get a (strict or not-strict)decreasing sub sequence of a list? >> = > ---------------- >> >> increasing = > ? > > Try using Split. > > In[185]:= lst=RandomInteger[{1,5},20] > Out[185]= {4,3,4,2,4,1,3,5,3,2,3,4,3,4,2,5,5,5,5,5} > > In[186]:= Split[lst, #1 >= #2 &] > Out[186]= {{4, 3}, {4, 2}, {4, 1}, {3}, {5, 3, 2}, {3}, {4, 3}, {4, > 2}, {5, 5, 5, 5, 5}} > > Then you can find the longest non-strictly decreasing sub sequence as > follows. > > In[187]:= m = Max[Length /@ %]; > Select[%%, Length[#] == m &] > > Out[188]= {{5, 5, 5, 5, 5}} > > Sam > -- DrMajorBob at yahoo.com
- References:
- Re: how to get the longest ordered sub sequence of a list in
- From: Emu <samuel.thomas.blake@gmail.com>
- Re: how to get the longest ordered sub sequence of a list in