Array CountIf Substitute - Count(Match())

Question

Core Question

How can I perform repeated CountIf()s on a range as efficiently (performance-wise) as possible?

Concerns in Detail

Answer 1

Solution - Count(Match())

The solution we are looking for is:

Application.Count(Application.Match(SavedArray(), Array([lookup_value]), 0))

What? How does that work? --- How can a function that normally returns a row number be paired with an array and count to return the correct answer? How can you count row numbers?

Explanation of Mechanics

With many thanks to @Jeeped, here's how it works:

It's an undocumented feature of Match(lookup value, lookup array, 0) that if you put an array as the lookup value, it will Match() each value in the array you entered against the lookup array. Thus, for the above example, for Loop = 1, it will become:

{match(A2, Array("1"), 0),match(A3, Array("1"), 0), ... match(A11, Array("1"), 0)}

Then, per @Jeeped:

Each match will either return a number or an error. The Count() function counts numbers, not errors. So you get a count of whether any of the values in A1:A11 match Loop1.

Final Code and Values

Sub M1ArrayCount()

Dim arrNumbers() As Variant
Dim Long1 As Long
Dim Loop1 As Long

arrNumbers() = ThisWorkbook.Sheets(1).Range("A2:A11").Value

With ThisWorkbook.Sheets(1)
    For Loop1 = 1 To 6
        .Cells(Loop1 + 1, 4).Value = Application.Count(Application.Match(arrNumbers(), Array(Loop1), 0))
    Next Loop1
End With

End Sub

References --- This comment

This answer

Question

Example:

myarray = array("First","Second","Second","Third","Fourth")

then what would the countif(myarray,"second") syntax be? (the result should equal 2 counts)

Answer

Try also:

MsgBox Application.Count(Application.Match(myArray, Array("Second"), 0))

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