LBound function
LBound( array [,dimension] )
Returns the smallest available subscript for the dimension of the indicated array.
Example
' This example demonstrates some of the features of arrays.  The
' lower bound for an array is 0 unless it is specified or option
' base has set as is done in this example.
 
Option Base 1
 
Sub Main
   Dim a(10) As Double
   MsgBox "LBound: " & LBound(a) & " UBound: " & UBound(a)
   Dim i As Integer
   For i = 0 to 3
       a(i) = 2 + i * 3.1
   Next i
   Print a(0),a(1),a(2), a(3)
End Sub