Rotating a list

I have a closed loop list like

loop(1)=      19
loop(2)=      33
loop(3)=      32
loop(4)=      31
loop(5)=      6
loop(6)=      10
loop(7)=      11
loop(8)=      19

I would like to have a macro which will find the minimum number (here it is 6) and rotate the list so that the list starts with that number giving

loop(1)=      6
loop(2)=      10
loop(3)=      11
loop(4)=      19
loop(5)=      33
loop(6)=      32
loop(7)=      31
loop(8)=      6
LVL 43
Saqib Husain, SyedEngineerAsked:
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byundtCommented:
Collection rotating sub:
Sub RotateLoop(vLoop As Collection)
Dim dMin As Double
Dim i As Long, iMin As Long, n As Long
n = vLoop.Count
dMin = 1E+307
For i = 1 To n
    If vLoop(i) < dMin Then
        iMin = i
        dMin = vLoop(i)
    End If
Next
If iMin > 1 Then
    vLoop.Remove n
    For i = 1 To iMin
        vLoop.Add vLoop(1)
        If i < iMin Then vLoop.Remove 1
    Next
End If
End Sub

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Raheman M. AbdulSenior Infrastructure Support Analyst & Systems DeveloperCommented:
Where did you store the numbers in the list?
Where do you want the output list?
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byundtCommented:
There may be a more elegant way of doing it, but here is code that uses an intermediate array for rewriting the list.
Sub Test()
Dim vLoop(1 To 8) As Variant, vResult As Variant
Dim i As Long
vLoop(1) = 19
vLoop(2) = 33
vLoop(3) = 32
vLoop(4) = 31
vLoop(5) = 6
vLoop(6) = 10
vLoop(7) = 11
vLoop(8) = 19
RotateLoop vLoop
For i = 1 To 8
    Debug.Print i & "    " & vLoop(i)
    Next
End Sub

Sub RotateLoop(vLoop As Variant)
Dim dMin As Double
Dim v As Variant
Dim i As Long, iMin As Long, iFirst As Long, iLast As Long, j As Long, k As Long
iFirst = LBound(vLoop)
iLast = UBound(vLoop)
ReDim v(iFirst To iLast)
dMin = Application.Min(vLoop)
iMin = Application.Match(dMin, vLoop, 0) + iFirst - 1
j = iFirst
For i = iMin To iLast
    v(j) = vLoop(i)
    j = j + 1
Next
If iMin > iFirst Then
    For i = iFirst To iMin - 1
        v(j) = vLoop(i)
        j = j + 1
    Next
End If
For i = iFirst To iLast
    vLoop(i) = v(i)
Next
End Sub

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Saqib Husain, SyedEngineerAuthor Commented:
Thanks, Brad, but the result does not match the desired result. The original loop starts at 19 and ends at 19. The transformed loop should start at 6 and end at 6.

Would it be also possible to have vLoop as a collection object?
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byundtCommented:
I can add the "repeat the starting value at end of list" feature by adding two statements to the original code:
Sub RotateLoop(vLoop As Variant)
Dim dMin As Double
Dim v As Variant
Dim i As Long, iMin As Long, iFirst As Long, iLast As Long, j As Long, k As Long
iFirst = LBound(vLoop)
iLast = UBound(vLoop)
ReDim v(iFirst To iLast)
dMin = Application.Min(vLoop)
iMin = Application.Match(dMin, vLoop, 0) + iFirst - 1
j = iFirst
For i = iMin To iLast - 1
    v(j) = vLoop(i)
    j = j + 1
Next
If iMin > iFirst Then
    For i = iFirst To iMin - 1
        v(j) = vLoop(i)
        j = j + 1
    Next
End If
v(iLast) = v(iFirst)
For i = iFirst To iLast
    vLoop(i) = v(i)
Next
End Sub

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Before I embark upon modifying the code to work with a collection, could you be more specific about which property of the objects in the collection should be minimized?
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Saqib Husain, SyedEngineerAuthor Commented:
I am not sure about what you mean by
which property of the objects in the collection should be minimized?


I have something like

Sub Test()
Dim vLoop As New Collection
Dim vResult As Variant
Dim i As Long
vLoop.Add 19
vLoop.Add 33
vLoop.Add 32
vLoop.Add 31
vLoop.Add 6
vLoop.Add 10
vLoop.Add 11
vLoop.Add 19
RotateLoop vLoop
For i = 1 To 8
    Debug.Print i & "    " & vLoop(i)
    Next
End Sub
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Saqib Husain, SyedEngineerAuthor Commented:
Perfect, thanks
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