# Excel/combin() function

Question
QUESTION: I am using the combin() function. I am looking for a way to display the listings and not just the output of the formula. e.g. combin(5,2) = 10 possible combinations. I would like to be able to pout put the 10 values. 1&2, 1&3, 1&4, 1&5, 2&3,2&4,2&5, 3&4,3&5,4&5 are the combinations.

I tried a few VBA samples from the internet, but can't seem to get them working.

ANSWER: Put the 5 items in column F,
Run macro comb8:

Dim CurrentRow

Sub Comb8()
lmt = Application.CountA(Range("F:F"))
[a:a].ClearContents
[a1].Select
'''Generate combinations of 8 items taken 1 thru 8 at a time
For i = 1 To lmt
'Single apostrophe surrounded by quotes
Comb lmt, i, 1, "'"
Next
Application.Goto Range("A1"), True
For i = 1 To lmt
[a:a].Replace i, Cells(i, 6).Value
Next
'remove items which aren't a pair:
For i = 1 To Cells(Rows.Count, 1).End(xlUp).Row
If Len(Cells(i, 1).Value) - Len(Application.Substitute(Cells(i, 1).Value, " ", "")) <> 2 Then Cells(i, 1).ClearContents
Next
End Sub

'''Generate combinations of integers k..n taken m at a time, recursively
Sub Comb(ByVal n As Integer, ByVal m As Integer, _
ByVal k As Integer, ByVal s As String)
If m > n - k + 1 Then Exit Sub
If m = 0 Then
ActiveCell = s
ActiveCell.Offset(1, 0).Select
Exit Sub
End If
Comb n, m - 1, k + 1, s & k & " "
Comb n, m, k + 1, s
End Sub

[an error occurred while processing this directive]---------- FOLLOW-UP ----------

QUESTION: That worked for combin(5,2). Not sure how it knows the number of items in each combination. e.g combin(5,4) retruns 5 values. It would be nice if it could work off of a Private Function where the 2 values of (5,4) for example were input and then the macro launched displaying the 5 items. Any combination is possible for this application of course.

Put the number of items in each combination in cel G1. Run this:

Sub Comb8()
lmt = Application.CountA(Range("F:F"))
[a:a].ClearContents
[a1].Select
'''Generate combinations of 8 items taken 1 thru 8 at a time
For i = 1 To lmt
'Single apostrophe surrounded by quotes
Comb lmt, i, 1, "'"
Next
Application.Goto Range("A1"), True
For i = 1 To lmt
[a:a].Replace i, Cells(i, 6).Value
Next
'remove items which aren't a pair:
For i = 1 To Cells(Rows.Count, 1).End(xlUp).Row
If Len(Cells(i, 1).Value) - Len(Application.Substitute(Cells(i, 1).Value, " ", "")) <> Range("G1").Value Then Cells(i, 1).ClearContents
Next
End Sub

'''Generate combinations of integers k..n taken m at a time, recursively
Sub Comb(ByVal n As Integer, ByVal m As Integer, _
ByVal k As Integer, ByVal s As String)
If m > n - k + 1 Then Exit Sub
If m = 0 Then
ActiveCell = s
ActiveCell.Offset(1, 0).Select
Exit Sub
End If
Comb n, m - 1, k + 1, s & k & " "
Comb n, m, k + 1, s
End Sub
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