I used this code to create 100000 numbers (12 digit unique random numeric numbers )
Sub uniqueramdom()
Const strCharacters As String = "0123456789"
Dim cllAlphaNums As Collection
Dim arrUnqAlphaNums(1 To 60000) As String
Dim varElement As Variant
Dim strAlphaNum As String
Dim AlphaNumIndex As Long
Dim lUbound As Long
Dim lNumChars As Long
Dim i As Long
Set cllAlphaNums = New Collection
lUbound = UBound(arrUnqAlphaNums)
lNumChars = Len(strCharacters)
On Error Resume Next
Do
strAlphaNum = vbNullString
For i = 1 To 12
strAlphaNum = strAlphaNum & Mid(strCharacters, Int(Rnd() * lNumChars) + 1, 1)
Next i
cllAlphaNums.Add strAlphaNum, strAlphaNum
Loop While cllAlphaNums.Count < lUbound
On Error GoTo 0
For Each varElement In cllAlphaNums
AlphaNumIndex = AlphaNumIndex + 1
arrUnqAlphaNums(AlphaNumIndex) = varElement
Next varElement
Range("A1").Resize(lUbound).Value = Application.Transpose(arrUnqAlphaNums)
Set cllAlphaNums = Nothing
Erase arrUnqAlphaNums
End Sub
It works with: Dim arrUnqAlphaNums(1 To 50000) As String
But with: Dim arrUnqAlphaNums(1 To 100000) As String
, it not working and producing Error : type mismatch
I have the following code in here http://www.excelforum.com/
you have hit the limitation of Transpose. the below would work
Dim arrUnqAlphaNums(1 To 65536 ) As String 'remember the number 65536?
this wont work
Dim arrUnqAlphaNums(1 To 65537 ) As String
You will find that this limitation inherited on ranges from prior versions of Excel. Microsoft may have left some business incomplete
you could probably refactor the code as below
Option Explicit
Sub uniqueramdom()
Const strCharacters As String = "0123456789"
Dim strAlphaNum As String
Dim AlphaNumIndex As Long
Dim lUbound As Long
Dim lNumChars As Long
Dim i As Long
Dim iRow As Long
iRow = 1
lUbound = 100000 'Change here your ubound. This can increase execution time.
lNumChars = Len(strCharacters)
On Error Resume Next
Do
strAlphaNum = vbNullString
For i = 1 To 12
strAlphaNum = strAlphaNum & Mid(strCharacters, Int(Rnd() * lNumChars) + 1, 1)
Next i
Cells(iRow, 1) = strAlphaNum
iRow = iRow + 1
Loop While iRow <= lUbound
On Error GoTo 0
End Sub
You were running into an old functional size limitation of application.transpose
. If you move to a 2-D array and fill the proper rank, you should not require the use of transpose at all.
Sub uniqueramdom()
Const strCharacters As String = "0123456789"
Dim cllAlphaNums As Collection
Dim arrUnqAlphaNums(1 To 100000, 1 To 1) As String
Dim varElement As Variant
Dim strAlphaNum As String
Dim AlphaNumIndex As Long
Dim lUbound As Long
Dim lNumChars As Long
Dim i As Long
Set cllAlphaNums = New Collection
lUbound = UBound(arrUnqAlphaNums, 1)
lNumChars = Len(strCharacters)
On Error Resume Next
Do
strAlphaNum = vbNullString
For i = 1 To 12
strAlphaNum = strAlphaNum & Mid(strCharacters, Int(Rnd() * lNumChars) + 1, 1)
Next i
cllAlphaNums.Add strAlphaNum, strAlphaNum
Loop While cllAlphaNums.Count < lUbound
On Error GoTo 0
For Each varElement In cllAlphaNums
AlphaNumIndex = AlphaNumIndex + 1
arrUnqAlphaNums(AlphaNumIndex, 1) = varElement
Next varElement
Range("A1").Resize(lUbound) = arrUnqAlphaNums
Set cllAlphaNums = Nothing
Erase arrUnqAlphaNums
End Sub