Golf Trip Pairings w/ No Repeats

[pstoller]

We have a 32-man golf trip that is split up into 2 teams of 16. We play 4 rounds. I am trying to come up with a schedule where everyone has a different partner all 4 rounds, and everyone will play against different people on the opposing team over the 4 rounds (8 in total), with no overlap or repeats. If it's even possible I figure there has to be a formula but for the life of me can't figure it out. Any help would be greatly appreciated.

 

[arc6th]

If everything can be truly random. I'd assign each player a RAND() number and convert to value. Sort each team by that number--low-to-high. The lowest of each team is Player 1. The highest is Player 16. Then I'd shift the players manually by one slot for each round.
Rd 1: 1 vs 1, 2 vs 2, 3 vs 3, 4 vs 4, etc...
Rd 2: 1 vs 16, 2 vs 1, 3 vs 2, 4 vs 3, etc...
Rd 3: 1 vs 15, 2 vs 16, 3 vs 1, 4 vs 2, etc...
Rd 4: 1 vs 14, 2 vs 15, 3 vs 16, 4 vs 1, etc...

If shifting by one slot is too predictable I might have Excel select another random number between 1 and 15 to determine the shift.

It's not sophisticated, but it's not difficult, either.

 

[lrobbo314]

***edit

 

[AhoyNC]

See attached (free) golf pairing generator web site.

Free round robin tournament schedule / pairings generator – GolfSoftware.com

Use our free round robin tournament generator to create your single round robin, double round robin or play with all schedule for your tournaments and leagues.

golfsoftware.com

 

[lrobbo314]

Attempt #2 at VBA solution.

Team Rank Golf VBA.xlsm
	E	F	G	H	I	J	K	L
1	Round 1		Round 2		Round 3		Round 4
2	Europe	USA	Europe	USA	Europe	USA	Europe	USA
3	1	7	1	5	1	4	1	13
4	2	5	2	12	2	10	2	14
5	3	2	3	7	3	16	3	13
6	4	8	4	6	4	15	4	14
7	5	6	5	8	5	4	5	15
8	6	2	6	6	6	8	6	16
9	7	7	7	4	7	6	7	11
10	8	10	8	1	8	14	8	13
11	9	5	9	7	9	2	9	14
12	10	4	10	6	10	10	10	1
13	11	16	11	12	11	11	11	2
14	12	12	12	4	12	5	12	3
15	13	5	13	11	13	2	13	4
16	14	12	14	13	14	15	14	7
17	15	15	15	11	15	7	15	12
18	16	4	16	15	16	12	16	10
Sheet7

Sub Golf()
Application.ScreenUpdating = False
Application.DisplayAlerts = False
Application.EnableEvents = False

Dim Teams As Integer:       Teams = 16
Dim AA() As Object:         ReDim AA(1 To Teams)
Dim AL As Object:           Set AL = CreateObject("System.Collections.ArrayList")
Dim r As Range:             Set r = Range("E3:E18")
Dim SP() As String
Dim v As Variant

For k = 1 To UBound(AA)
    Set AA(k) = CreateObject("System.Collections.ArrayList")
Next k

For i = 0 To Teams - 1
    For j = 0 To Teams - 1
        v = i + 1
        AA(v).Add Join(Array(v, ((j) Mod Teams) + 1), ",")
    Next j
Next i

For col = 1 To 4
    For ro = 1 To Teams
        Randomize
        ri = Int(AA(ro).Count * Rnd())
        SP = Split(AA(ro).Item(ri), ",")
        AL.Add AA(ro).Item(ri)
        AA(ro).removeAt (ri)
        AA(SP(1)).Remove (SP(1) & "," & SP(0))
    Next ro
    With r
        .Value = Application.Transpose(AL.toArray)
        .TextToColumns DataType:=xlDelimited, Comma:=True
    End With
    Set r = r.Offset(, 2)
    AL.Clear
Next col

Application.ScreenUpdating = True
Application.DisplayAlerts = True
Application.EnableEvents = True
End Sub

 

[lrobbo314]

The above post was closer, but I'm seeing an issue with it again.

 

[pstoller]

So the problem here, aside from the duplicate numbers in the USA column, but also having the Europe team be 1-16 for each round, assuming every 2 rows they would be grouped as teammates for that match then Europe would have the same partner all 4 rounds.

 

[pstoller]

I got it. I couldn't figure out an Excel formula, ended up just manually moving things around until everything checked out. Thanks for the help and suggestions.