MathGroup Archive 2003

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Re: split a list

  • To: mathgroup at smc.vnet.net
  • Subject: [mg40627] Re: [mg40552] Re: [mg40515] split a list
  • From: Dr Bob <majort at cox-internet.com>
  • Date: Fri, 11 Apr 2003 02:04:15 -0400 (EDT)
  • References: <200304100736.DAA24139@smc.vnet.net>
  • Reply-to: majort at cox-internet.com
  • Sender: owner-wri-mathgroup at wolfram.com

Complement doesn't work, because it returns a sorted list.

Bobby

On Thu, 10 Apr 2003 03:36:40 -0400 (EDT), <Gary.Anderson at frb.gov> wrote:

>
> roberto,
>
> how about
> u=Select[r,#<m&];v=Select[r,#>m&]  but what about ==?
> alternatively,
> v=Complement[r,u=Select[r,#<m&]];
>
>
>
> Roberto                                                                   
> Brambilla            To:     mathgroup at smc.vnet.net                       
> <rlbrambilla@        cc:                                                  
> cesi.it>             Subject: [mg40627] [mg40552]     [mg40515] split a list
>
> 04/09/03                                                                  
> 01:30 AM
>
>
>
>
>
>
>
> Hi,
>
> I have a list (very long, thousands, and unsorted) of numbers 
> r={n1,n2...}
> and for a given a number m  I want to split it in the two sublists
> (unsorted, same order) u={elements<m], v={elements>m}.
> Now I use this *old-style*  method:
>
> u = v = {};
> For[i = 1, i <= Length[r], i++,
> tmp = r[[i]];
> If[tmp > m , AppendTo[u, tmp], AppendTo[v, tmp]];
> ]
>
> Any suggestion for a more efficient (and elegant) method?
> Also oneliners are well accepted.
>
> Many thanks, Roberto
>
> Roberto Brambilla
> CESI
> Via Rubattino 54
> 20134 Milano
> tel +39.02.2125.5875
> fax +39.02.2125.5492
> rlbrambilla at cesi.it
>
>
>
>
>
>
>
>



-- 
majort at cox-internet.com
Bobby R. Treat



  • Prev by Date: Weirdness with symbol Degree vis Units
  • Next by Date: Re: Integration problem
  • Previous by thread: Re: split a list
  • Next by thread: Re: split a list