Mathematica 9 is now available
Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
2007
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 2007

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

Search the Archive

Re: Sorting by date

  • To: mathgroup at smc.vnet.net
  • Subject: [mg72675] Re: [mg72637] Sorting by date
  • From: Bob Hanlon <hanlonr at cox.net>
  • Date: Sun, 14 Jan 2007 05:26:59 -0500 (EST)
  • Reply-to: hanlonr at cox.net

A shorter and quicker way than my first approach is     data[[Ordering[Last/@data]]]

data={{3,137.5,13978,{2005,2,8}},
      {3,138.5,12519,{2005,1,4}},
      {3,171.9,15835,{2005,4,12}},
      {3,142.8,17137,{2005,11,19}},
      {3,161.1,18881,{2006,1,18}},
      {3,108.7,20055,{2006,2,28}},
      {3,157,21498,{2006,9,14}},
      {3,118.1,10891,{2004,11,12}}};

Timing[Sort[data, Last[#1].(10^{4,2,1})<Last[#2].(10^{4,2,1})&];]

{0.011517 Second,Null}

Timing[data[[Ordering[Last/@data]]];]

{0.000259 Second,Null}

Sort[data, Last[#1].(10^{4,2,1})<Last[#2].(10^{4,2,1})&]==
  data[[Ordering[Last/@data]]]

True


Bob Hanlon

---- Bob Hanlon <hanlonr at cox.net> wrote: 
> data={{3,137.5,13978,{2005,2,8}},
>       {3,138.5,12519,{2005,1,4}},
>       {3,171.9,15835,{2005,4,12}},
>       {3,142.8,17137,{2005,11,19}},
>       {3,161.1,18881,{2006,1,18}},
>       {3,108.7,20055,{2006,2,28}},
>       {3,157,21498,{2006,9,14}},
>       {3,118.1,10891,{2004,11,12}}};
> 
> Sort[data, Last[#1].(10^{4,2,1})<Last[#2].(10^{4,2,1})&]
> 
> {{3,118.1,10891,{2004,11,12}},{3,138.5,12519,{2005,1,4}},{3,
>   137.5,13978,{2005,
>     2,8}},{3,171.9,15835,{2005,4,12}},{3,142.8,17137,{2005,11,19}},{3,
>     161.1,18881,{2006,1,18}},{3,108.7,20055,{2006,2,28}},{
>     3,157,21498,{2006,9,14}}}
> 
> 
> Bob Hanlon
> 
> ---- Clifford Martin <camartin at snet.net> wrote: 
> > Hi All,
> > 
> > I have a list of lists that looks like so:
> > 
> > 
> > {{3, 137.5, 13978, {2005, 2, 8}}, {3, 138.5, 12519, {2005, 1, 4}}, {3, 171.9, 15835, {2005, 4, 12}}, {3, 142.8, 17137, {2005, 11, 19}}, 
> >   {3, 161.1, 18881, {2006, 1, 18}}, {3, 108.7, 20055, {2006, 2, 28}}, {3, 157, 21498, {2006, 9, 14}}, {3, 118.1, 10891, {2004, 11, 12}}}
> > 
> > The last element per vector is a date. I'd like to sort the list so that the vectors are arranged in ascending order of date, i.e. the vector containing {2004,11,12}  should be first and and the vector containing {2006,9,14}  should be last. Any help would be appreciated.
> > 
> > Thanks
> > 
> > Cliff
> > 


  • Prev by Date: Re: Sorting by date
  • Next by Date: RE: Re: Re: Limit and Root Objects
  • Previous by thread: Re: Sorting by date
  • Next by thread: Re: Sorting by date