How do I extract values from a range without headers in VBA Excel and store them in a 1D array?

Question

How to eficiently flatten a range or a 2D Array into a 1D array excluding the header? Example: Range("A1:A10") where:

Range("A1") is a header Range("A2:A10") contains data.

I need to convert the entire range (Range("A1:A10")) into a 1D Array containig the values from

Range("A2:A10").

Thanks a lot to everyone.

I tried several versions of Transpose(Index...)) and no results.

Answer 1

Function that returns a 1 dimensional array from a range rng, optionally ignoring the first hdr_rows number of cells :

Function range_to_1d_array(rng As Range, Optional hdr_rows As Long = 0) As Variant
    Set BodyRange = rng.Offset(hdr_rows).Resize(rng.Rows.Count - hdr_rows)
    range_to_1d_array = Application.Transpose(Application.Index(BodyRange, 0, 1))
End Function

To use this to read your A1:A10 (ignoring 1st row):

myArr = range_to_1d_array(rng:=Range("A1:A10"), hdr_rows:=1)

To see this in action:

Sub test()
    myArr = range_to_1d_array(rng:=Range("A1:A10"), hdr_rows:=1)
    For Each arrayvalue In myArr
        Debug.Print arrayvalue
    Next
End Sub

Or you can request specific values using:

    myArr = range_to_1d_array(rng:=Range("A1:A10"), hdr_rows:=1)
    thirdvalue = myArr(3)

Note:

The Transpose function has an internal limitation of 65,535 cells. If you're looking for more than that I'd suggest a manual (looping) process as provided by other answers here.

Answer 2

Single-Column Values To 1D Array

Sub ColumnToArray()

    Const FIRST_CELL As String = "A1"
    Const HEADER_ROWS As Long = 1
    Const ARRAY_LOWER_LIMIT As Long = 0
    
    Dim ws As Worksheet: Set ws = ActiveSheet ' improve!
     
    Dim rg As Range, rCount As Long
    With ws.Range(FIRST_CELL)
        rCount = ws.Cells(ws.Rows.Count, .Column).End(xlUp).Row _
            - .Row - HEADER_ROWS + 1 
        If rCount < HEADER_ROWS Then Exit Sub ' nothing or just some headers
        Set rg = .Offset(HEADER_ROWS).Resize(rCount)
    End With
    
    Dim Data()
        
    If rCount = 1 Then
        ReDim Data(1 To 1, 1 To 1): Data(1, 1) = rg.Value
    Else
        Data = rg.Value
    End If
    
    Dim rDiff As Long: rDiff = 1 - ARRAY_LOWER_LIMIT
    Dim Arr(): ReDim Arr(ARRAY_LOWER_LIMIT To rCount - rDiff)
    
    Dim r As Long
    
    For r = 1 To rCount
        Arr(r - rDiff) = Data(r, 1)
    Next r
    
    Debug.Print Join(Arr, ", ") & vbLf _
        & "Array Limits [" & LBound(Arr) & "," & UBound(Arr) & "]"
    
End Sub

Result

1, 2, 5, 3, 7, 9, , , 10
Array Limits [0,8]

Answer 3

Consider this sheet:

Using VBA you can get the data like this:

Sub GetValues()
    Dim arrValues()
    
    arrValues = Range("A2:A10")
    
    For Each c In arrValues
        Debug.Print c
    Next
End Sub

A range can be directly assigned to an array. The array items will hold the call data.

Output:

value1
value2
value3
value4
value5
value6
value7
value8
value9

Answer 4

To efficiently flatten a range or a 2D array into a 1D array excluding the header, you can use the following approach:

Function FlattenRange(rng As Range) As Variant
Dim dataRange As Range
Dim dataArray As Variant
Dim resultArray As Variant
Dim i As Long

' Exclude the header row
Set dataRange = rng.Offset(1).Resize(rng.Rows.Count - 1)

' Convert the range to a 2D array
dataArray = dataRange.Value

' Determine the size of the result array
ReDim resultArray(1 To UBound(dataArray, 1))

' Copy the values from the 2D array to the result array
For i = 1 To UBound(dataArray, 1)
    resultArray(i) = dataArray(i, 1)
Next i

FlattenRange = resultArray
End Function

To use this function, you can call it with your range as an argument and assign the returned 1D array to a variable. Here's an example:

Sub TestFlattenRange()
Dim rng As Range
Dim flattenedArray As Variant

' Define your range
Set rng = Range("A1:A10")

' Call the FlattenRange function
flattenedArray = FlattenRange(rng)

' Display the flattened array values
Dim i As Long
For i = LBound(flattenedArray) To UBound(flattenedArray)
    Debug.Print flattenedArray(i)
Next i
End Sub

This code will exclude the header row and convert the range into a 1D array (flattenedArray) containing the values from the remaining rows. You can modify it to suit your specific needs.

Answer 5

Function Flatten() with optional header cut and/or rebase action

Returns an x-based 1D array removing the header via Filter() function and allowing to rebase to any lower boundary:

Function Flatten(rng As Range, _
    Optional cutHeader As Boolean = True, _
    Optional newBase As Long = 0)
'Note: assumes optional header row in a one-column range
Const DEL = "$DEL$"
'a) get a "flat" 1D array
    Dim tmp:  tmp = Application.Transpose(rng.Value2)
'b) remove header (optional)
    If cutHeader Then tmp(LBound(tmp)) = DEL
    tmp = Filter(tmp, DEL, False)   ' Filter always returns a 0-based array)
'c) rebase to newBase(optional)
    If newBase Then
        ReDim Preserve tmp(newBase To UBound(tmp) + newBase)
    End If
'd) return function result as 1D x-based array
    Flatten = tmp
End Function

---

Example Calls

Sub ExampleCalls()
'A) Define Range
    Dim rng As Range: Set rng = Tabelle1.Range("A1:A10")
    
'B) Example calls
    Dim result As Variant

    'Example 1) 1D 0-based array with header
    result = Flatten(rng, False)
    display result, False

    'Example 2) 1D 0-based array without header
    result = Flatten(rng)                        ' cut header (default)
    display result

    'Example 3) 1D 3-based array without header
    result = Flatten(rng, True, 3)               ' cut header explicitly AND rebase
    display result

End Sub

Helper procedure Display()

Displays results in VB Editor's immediate window:

Sub display(flatArr, Optional cutHeader As Boolean)
    Static cnt As Long: cnt = IIf(cnt, cnt + 1, 1)
    Debug.Print cnt & ") Boundaries " & _
        IIf(cutHeader, "w/o ", "with") & _
        " header: (" & LBound(flatArr) & " To " & UBound(flatArr) & ")" & vbNewLine & vbTab & _
        Join(flatArr, "|")
End Sub

Answer 6

**

The shortest way to convert a Range into a one-dimensional array

and probably the fastest (so far). Οptionally trim headers (hdrRows=0)

There are two versions:

a) Range has one column and many rows (headers above)

b) Range has one row and many columns. (headers left)

The result will in both cases be a one-dimensional array of Range values. In addition to these two basic Functions, I also publish an auxiliary one that uses both.

'VERTICAL RANGE (ONE COLUMN) TO ONE DIMENTIONAL ARRAY
Function colRngTo1Darr(r As Range, Optional hdrRows As Long = 0) As Variant
   colRngTo1Darr = Application.Transpose(IIf(hdrRows = 0, r.Value2, r.Offset(hdrRows).Resize(r.Rows.CountLarge - hdrRows).Value2))
End Function


'HORIZONTAL RANGE (ONE ROW) TO ONE DIMENTIONAL ARRAY
Function rowRngTo1Darr(r As Range, Optional hdrRows As Long = 0) As Variant
   rowRngTo1Darr = Application.Transpose(Application.Transpose(IIf(hdrRows = 0, r, r.Offset(0, hdrRows).Resize(1, r.Columns.CountLarge - hdrRows))))
End Function


'THIS IS A HELPER FUNCTION WHEN NEEDS THE SAME ENTRY POINT FOR HORIZONTAL and
'VERTICAL RANGES tranformation
'HORIZONTAL or VERTICAL RANGE (ONE ROW or ONE COLUMN) TO ONE DIMENTIONAL ARRAY
Public Function rngTo1Darr(rng As Range, Optional hdrRows As Long = 0) As Variant
   If rng.Columns.CountLarge = 1 Then
      rngTo1Darr = colRngTo1Darr(rng, hdrRows)
   ElseIf rng.Rows.CountLarge = 1 Then
      rngTo1Darr = rowRngTo1Darr(rng, hdrRows)
   Else
      MsgBox ("rngTo1Darr> invalid range dimentions " & rng.Address)
   End If
End Function

The bounds of the solution I'm posting match the bounds of "Application.Transpose"