sharing/swapping items between lists

[Ross]

On Apr 14, 10:34 am, Ross <ross.j... at gmail.com> wrote:
> On Apr 14, 5:57 am, a... at pythoncraft.com (Aahz) wrote:
>
>
>
> > In article <f64c9de2-3285-4f74-adb8-2111c78b7... at 37g2000yqp.googlegroups.com>,
>
> > Ross  <ross.j... at gmail.com> wrote:
> > >On Apr 13, 9:08=A0am, a... at pythoncraft.com (Aahz) wrote:
> > >> In article <c569228f-f391-4317-83a2-08621c601... at r8g2000yql.googlegroups.=
> > >com>,
> > >> Ross =A0<ross.j... at gmail.com> wrote:
>
> > >>>I'm sorry...my example was probably a bad one. A better example of
> > >>>output I would like would be something like [[1,2],[3,4],[5,6]] and
> > >>>then for the leftovers list [7,8,9,10 etc]. What I'm trying to do is
> > >>>produce some sort of round robin algorithm for tennis that is
> > >>>constrained by the number of courts available each week. So if there
> > >>>are only 3 courts available for a singles league and 10 people have
> > >>>signed up, 4 players will have a bye each week. I want my algorithm to
> > >>>produce unique matchups each week and also give each player the same
> > >>>angle?
>
> > >> How about Googling for "round robin algorithm python"? ;-)
>
> > >I have the basic algorithm and it works fine...I'm just having trouble
> > >adding another parameter to it that allows for court constraints and
> > >bye weeks.
>
> > You'll need to give us more information, then.  Why don't you start with
> > the core algorithm you're using?
> > --
> > Aahz (a... at pythoncraft.com)           <*>        http://www.pythoncraft.com/
>
> > Why is this newsgroup different from all other newsgroups?
>
> Here's the core algorithm I'm using:
>
> >>> def round_robin(teams,rounds):
>
>         if len(teams)%2:
>                 teams.append(None)
>         mid = len(teams) //2
>         for i in range(rounds):
>                 yield zip(teams[:mid], teams[mid:])
>                 teams = teams[0:1] + teams[mid:mid+1] + teams[1:mid-1]+teams[mid
> +1:]+teams[mid-1:mid]
>
> >>> if __name__== '__main__':
>
>         rounds = 15
>         teams = range(16)
>         for round in round_robin(teams,rounds):
>                 print round

fyi rounds=15 and teams =range(16) was just test code I was playing
around with...they could theoretically be anything.