How to get vba function array to return in excel

Question

Hello I am working on this project and I need to create a function in VBA in order to store a formula and return the result in excel using the index function. My code is as below and i created just a simple dummy function for testing purposes. In excel I believe the function should be =INDEX(NewArray,,1)? Any help on this would be greatly appreciated Thanks

Public Function NewArray(a As Integer, b As Integer) As Long()
Dim arr() As Long
ReDim arr(1 To 10, 1 To 5) As Long
Dim row As Integer
Dim col As Integer

For row = 1 To 5
arr(row, 1) = (row + 1)
 Next row

NewArray = arr(a, b)
End Function

Answer 1

Using a 'UDF Array' with INDEX

Option Explicit

''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' Purpose:      Creates a 2D one-based array with 'a' rows and 'b' columns.
'               populated by the product of rows and columns.
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Function NewArray(ByVal a As Long, ByVal b As Long) As Long()
    
    Dim arr() As Long: ReDim arr(1 To a, 1 To b)
    
    Dim r As Long
    Dim c As Long
    
    For r = 1 To a ' loop (iterate) through rows
        For c = 1 To b ' loop (iterate) through columns
            arr(r, c) = r * c ' e.g. product of the current row and column
        Next c
    Next r
    
    NewArray = arr ' don't forget to return the result

End Function

5 rows, 7 columns

• In VBA, return the elements of the array in the Immediate window ( Ctrl + G ).

Sub NewArrayTEST()

    Dim arr() As Long: arr = NewArray(5, 7)
    
    Dim r As Long
    Dim c As Long
    
    For r = 1 To UBound(arr, 1)
        For c = 1 To UBound(arr, 2)
            Debug.Print r, c, arr(r, c)
        Next c
    Next r

End Sub

• In Excel, you can return the element at the intersection of the 2nd row and the 3rd column using the INDEX function:

   =INDEX(NewArray(5,7),2,3)

• The result is 6 since we added the product 2*3 .