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11

Requests / 24 person RR across 5 courts

« Last post by Tennis76 on August 25, 2025, 05:12:37 PM »

Hi,

I’m trying to create a round robin schedule, and could use some help.

We are 24 players, across 5 courts, for a rotating-partners doubles tennis round robin. We will only have time for 9 or 10 rounds. I was thinking it might be best to divide the 24 players into two groups (by play level) to make the scheduling easier. For example, 10 players across 2 courts (8 playing, 2 sitting out each round) and 14 players across 3 courts (12 playing, 2 sitting out each round).

My questions are: is this the best way to split the players up? If so, could you give me a balanced schedule please for the 2 RR groups (of 10 and 14)? If not, what split do you suggest for 24 rotating doubles players across 5 courts with 9 (or 10 rounds)? And what would the best schedule be?

Thank you for any help!


Just an update here to help with the parameters I’m hoping to achieve:

- 24 players (can be split into 2 groups, I was thinking maybe a group of 10 and a group of 14)
- There are 5 courts available for each round
- A maximum of 10 rounds (9 would be better)
- Rotating partners so that each person plays with everyone once, and plays against each person at least once but not more than twice

Any help is much appreciated!!

12

Requests / Re: Golf pairings

« Last post by Ian Wakeling on August 16, 2025, 10:31:09 AM »

There really is no good schedule for 12 players in groups of 4 when there are only a handful of rounds, things get much easier if you can have 16 or more players. I have prepared the following schedule with your comment about wishing to balance each player's opponents as best possible, but this comes at the expense of having repeated partner pairs.

(A4 A3 v B1 B4) (A6 A5 v B2 B6) (A2 A1 v B3 B5)
(A3 A4 v B5 B2) (A5 A6 v B4 B3) (A2 A1 v B1 B6)
(A5 A4 v B3 B6) (A3 A1 v B2 B4) (A6 A2 v B1 B5)
(A1 A5 v B1 B5) (A4 A2 v B4 B2) (A6 A3 v B6 B3)

Team A has players A1 to A6, and team B has players B1 to B6. Each player opposes 4 members of the other team once, and the other 2 members twice. Hope that helps.

13

Requests / Golf pairings

« Last post by Groveroo on August 08, 2025, 11:36:37 AM »

I have 12 golfers split into two 6 man teams. We are playing 4 rounds of golf with 2 players from each team playing against each other in a scramble format. What would be the best pairings to limit the amount of times you would play against an opponent?

14

Requests / Golf pairings

« Last post by Groveroo on August 07, 2025, 04:09:25 PM »

I have 2 teams of 6. Playing in 2 man teams against each other for 4 rounds. What is the optimal pairings 

15

Requests / Re: 9 Teams 8 Events but hear me out

« Last post by Ian Wakeling on August 06, 2025, 03:43:27 AM »

If you look at reply #1 here from 2017, then (if you are logged in) there is a downloadable Excel file with a similar schedule to the one above, but for 14 teams in a 7x7 square.

16

Requests / Re: 9 Teams 8 Events but hear me out

« Last post by Ian Wakeling on August 05, 2025, 12:51:37 PM »

This is possible but there needs to be 9 rounds and 9 events - then each team has 8 intra-divisional games and 1 inter-divisional game and plays each event exactly once.  In the schedule below division 1 is teams A to I, and division 2 is teams J to R, all the inter-divisional games are on the main diagonal.  Because of the symmetry, rows and columns can be assigned to rounds and events either way.  Hope that helps.

(A J) (Q R) (D I) (C G) (B H) (M N) (E F) (O P) (K L)
(H I) (B K) (N Q) (L O) (P R) (E G) (C D) (J M) (A F)
(M R) (E H) (C L) (P Q) (F I) (B D) (K O) (A G) (J N)
(L P) (C F) (G H) (D M) (J K) (A I) (N R) (B E) (O Q)
(K Q) (G I) (O R) (A B) (E N) (C H) (J L) (D F) (M P)
(D E) (N P) (K M) (J R) (L Q) (F O) (A H) (C I) (B G)
(N O) (L M) (B F) (E I) (A C) (J Q) (G P) (K R) (D H)
(F G) (A D) (J P) (K N) (M O) (L R) (B I) (H Q) (C E)
(B C) (J O) (A E) (F H) (D G) (K P) (M Q) (L N) (I R)

17

Requests / 9 Teams 8 Events but hear me out

« Last post by YardGamesCo on August 04, 2025, 11:08:56 AM »

I know in a previous post it says it isn't possible because a team will have a bye every round. I was thinking of the Bye team playing a cross division game vs a Bye round team from another 9 team division to fix it.

Can I still see what it would look like for 8 rounds?

Thank you

18

Requests / Re: Memorial Tennis Round Robin

« Last post by Ian Wakeling on August 01, 2025, 03:00:14 AM »

Hi Don,

With 12 players there is actually no 3 court schedule possible - instead you would have to play it on 2 courts like this.  So there are 18 sessions in total where each player plays in 6 sessions, partnering and opposing each member of the opposite sex exactly once.

Regards,

Ian

19

Requests / Re: Memorial Tennis Round Robin

« Last post by Don Gray on July 31, 2025, 06:39:44 AM »

Ian,

It has been a while, but once again I need your assistance.  This time the algorithm has the following parameters:

• Mixed doubles tennis round robin - 6 men and 6 women
• 4 courts (or three if simpler)
• Each man plays with each woman against each man + partner
• All possible mixed doubles configurations. Am I right that this produces 36 sessions?

As always, your advice gratefully received.

Regards,

Don Gray.

20

Requests / Re: Bridge club schedule

« Last post by Ian Wakeling on July 26, 2025, 11:27:10 AM »

I am sorry that I can't offer a complete solution here, as the list of limitations is something I can't address, and as you will see later there are other issues as well. But I can offer some guidance on how I would approach this problem. The first thing to note is that it is possible to have every couple meet with every other couple exactly once in a 5 month period.  So it seems natural to look for a 15 round schedule where every pair of couples meet once in the first 5 months, meet once in months 6 to 10, and meet once in the last 5 months.  So this goes a long way towards meeting the "same pair two months in a row" criterion, as this can only happen in between each block of 5.  Of course this will be a month short, but I think I would attempt to do something special in the last month based on the couples' performance over months 1 to 15.

It is not actually possible to do as you ask: "to go to every pair's home over the two year period".  If there are 16 rounds, and every couple hosts 4 times, then they can only visit a maximum of 12 out of the 15 other homes.

If the social mixing is to be optimal, then you should try to avoid having the same 3, or the same 4 couples come together more than once. Or putting that another way, on the 3 occasions that couples A and B meet, the other 6 couples present should all be different.  It is possible to achieve this, and myschedule here in reply #1 shows you how to do it - just take any 3 of the 7 blocks.

As I have been experimenting with this problem, it's become apparent that my 3 blocks of 5 approach is not compatible with the idea of each couple having a long break between months where they host. So I can only offer the 15 month schedule below where quite often a couple hosts in 3 or 4 consecutive months. You could choose to reorder the 15 rounds to improve the breaks between hosting, but in the process you would make the breaks between seeing the same couple much worse.  So there is definitely a trade off here - you can not have everything that you ask for above.

So here is the 15 round (the 15 rows) schedule for 16 couples A to P. The square brackets give the hosts, so in round 1 from the 1st row, the four couples (I M O P) come together at M's home.

  Group 1  Group 2  Group 3  Group 4      Hosts
(A E G H) (B C D F) (I M O P) (J K L N)    [E B M L]
(O L F H) (I J C E) (G D N P) (A B K M)    [F C D M]
(N C M H) (O A J D) (F K E P) (G I B L)    [M O F L]
(L A C P) (M F G J) (D I K H) (E N O B)    [L M D E]
(C G K O) (B H J P) (D E L M) (F A N I)    [O B L I]
(J N A H) (K L E G) (B F I P) (C D M O)    [J K P D]
(C G B H) (D E F A) (K O J P) (L M N I)    [C D P N]
(I E O H) (J C L F) (A M G P) (B K D N)    [O J P K]
(E B M J) (D H L P) (F G N O) (A C I K)    [J P N K]
(N C E P) (O A B L) (F K M H) (G I J D)    [N B K J]
(G D F H) (A B C E) (O L N P) (I J K M)    [H A O I]
(N K E H) (O I B D) (F C M P) (G A J L)    [H I C G]
(M B L H) (N G I C) (E J D P) (F O A K)    [H G E A]
(K G B P) (L E F I) (C O J H) (D M N A)    [G E H A]
(B F J N) (A H I P) (C D K L) (E G M O)    [F A C G]

If you use this, then a couple will never visit another couple's home more than once.

The table below gives another way of looking at the schedule above, one row gives the movements for a single couple, so for example couple D starts by going to the home of couple B, then in month 2 the asterisk indicates that they host, while in month 3 they go to the home of couple O.

Couple/Round
                        1 1 1 1 1 1
      1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
      -----------------------------
  A | E M O L I J D P K B * G * * *
  B | * M L E * P C K J * A I H G F
  C | B * M L O D * J K N A * G H *
  D | B * O * L * * K P J H I E A C
  E | * C F * L K D O J N A H * * G
  F | B * * M I P D J N K H C A E *
  G | E D L M O K C P N J H * * * *
  H | E F M D B J C O P K * * * * A
  I | M C L D * P N O K J * * G E A
  J | L C O M B * P * * * I G E H F
  K | L M F D O * P * * * I H A G C
  L | * F * * * K N J P B O G H E C
  M | * * * * L D N P J K I C H A G
  N | L D M E I J * K * * O H G A F
  O | M F * E * D P * N B * I A H G
  P | M D F L B * * * * N O C E G A

Finally note that couples [B F I N] are the ones who host only 3 times in the 15 round schedule, so they should be the hosts for whatever happens in month 16.

Hope that is of some help.