Re: Re: Ten chess-players...

• To: mathgroup at smc.vnet.net
• Subject: [mg104289] Re: [mg104252] Re: Ten chess-players...
• From: danl at wolfram.com
• Date: Sun, 25 Oct 2009 23:25:24 -0500 (EST)
• References: <hbu7nh\$7g2\$1@smc.vnet.net>

```>
> <cmpbrn at gmail.com> wrote in message news:hbu7nh\$7g2\$1 at smc.vnet.net...
>> Given 10 (1 to 10) chess-players, in one day they play 5 games (1-2,
>> 6-10, 5-7, 4-8, 3-9).
>> Then they need 8 more days to complete the championship (one gamer
>> must play one time against any other player):
>> 1-3, 2-10, 6-7, 5-8, 4-9
>> 1-4, 2-3, 7-10, 6-8, 5-9
>> 1-5, 2-4, 3-10, 7-8, 6-9
>> 1-6, 2-5, 3-4, 7-9, 8-10
>> 1-7, 2-6, 3-5, 4-10, 8-9
>> 1-8, 2-7, 3-6, 4-5, 9-10
>> 1-9, 2-8, 3-7, 4-6, 5-10
>> 1-10, 2-9, 3-8, 4-7, 5-6
>>
>> How can I get the 10*(10-1)/2 = 45 pairs distributed in the 9x5
>> matrix?
>> What's about any other even number of players?
>>
>> Bruno
>>
>
> There is already websites to do round robin scheduling. You select the
> number of players, and it generates the pairings for you. Here is one for
> example
>
>
> Implementing the algorithm in Mathematica should not be hard. There are
> algorithms and source code in other languages shown on the web site for
> this
> as well (unless someone already did this in Mathematica).
>
> --Nasser

Here are some possibly relevant links.

http://demonstrations.wolfram.com/Tournaments/
http://demonstrations.wolfram.com/SocialGolferProblem/

http://mathworld.wolfram.com/Tournament.html
http://mathworld.wolfram.com/TournamentMatrix.html

Daniel Lichtblau
Wolfram Research

```

• Prev by Date: Re: ReplaceAll and rules from a list v7.0
• Next by Date: Re: Mathematica blogs
• Previous by thread: Re: Ten chess-players...
• Next by thread: Re: Ten chess-players...