Re: Ten chess-players...

*To*: mathgroup at smc.vnet.net*Subject*: [mg104252] Re: Ten chess-players...*From*: "Nasser M. Abbasi" <nma at 12000.org>*Date*: Sun, 25 Oct 2009 01:06:23 -0400 (EDT)*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 http://www.devenezia.com/downloads/round-robin/index.html 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