Excel VBA: MoviesByGenre Function - vba

Question

I am trying to write an Excel VBA function that will do two things. First, it will determine the number of movies in each genre and print it to the immediate window using the printMovieData function I have written. Secondly, it will return the genre that has the most number of movies using the FindMax function I have written. I have provided my codes for printMovieData, FindMax, and what I have so far for MoviesByGenre, however, I am not sure what I am doing wrong and am looking for help to get the function working. Currently, Excel is returning the #VALUE! error.
printMovieData:
Function printMovieData(title As String, arrayTopic, arrayOther)
printMovieData = ""
For i = 1 To UBound(arrayTopic)
Debug.Print arrayTopic(i) & " : " & arrayOther(i)
Next i
End Function
FindMax:
Function FindMax(valueArray, nameArray) As String
Dim i As Integer
Dim maxValue As Variant
maxValue = 0
For i = 1 To UBound(valueArray)
If valueArray(i) >= maxValue Then
maxValue = valueArray(i)
FindMax = nameArray(i)
End If
Next i
End Function
MoviesByGenre:
Function MoviesByGenre(genreRng As Range) As String
Dim i As Integer
Dim genreArray(1 To 4) As String
Dim countArray
genreArray(1) = Action
genreArray(2) = Comedy
genreArray(3) = Drama
genreArray(4) = Musical
For i = 1 To UBound(genreArray)
For j = 1 To genreRng.Count
If genreRng.Cells(j) = genreArray(i) Then
countArray(i) = countArray(i) + 1
End If
Next j
Next i
MoviesByGenre = printMovieData("Movies by Genre", genreArray, countArray)
MoviesByGenre = FindMax(countArray, genreArray)
End Function

Answer 1

TBH there are quite a lot of reasons why I wouldn't expect your code to work.
There are some assumptions made such as how you use genreRng.Count. This is assuming data to count is either one row or one column.
The following assumes that genreRng.Cells.Count, Ubound(genreArray) and UBound(countArray) are all the same. You don't ensure this.
There are missing variable declarations, no use of Option Explicit and a number of other things.
Overarching though, is that I think you want a different object to handle your count. This is where Collection and Scripting Dictionaries are very useful.
You can have the key as the genre and the count is held in the associated value. If the key already exists, i.e. a repeat genre, just add one to the existing count.
With that in mind, a starting point, might be something like (sorry, no error handling added):
Option Explicit
Public Sub test()
Dim genreCount As Object
Set genreCount = CreateObject("Scripting.Dictionary")
Set genreCount = MoviesByGenre(ActiveSheet.Range("A1:A3"), genreCount)
printMovieData "Movies by genre", genreCount
FindMax genreCount
End Sub
Public Function MoviesByGenre(ByRef genreRng As Range, ByVal genreCount As Object) As Object
Dim j As Long
For j = 1 To genreRng.Count 'assumes 1 column/row
Dim currentGenre As String
currentGenre = genreRng.Cells(j, 1)
If Not genreCount.Exists(currentGenre) Then
genreCount.Add currentGenre, 1
Else
genreCount(currentGenre) = genreCount(currentGenre) + 1
End If
Next j
Set MoviesByGenre = genreCount
End Function
Public Function printMovieData(ByVal title As String, ByVal genreCount As Object)
Dim key As Variant
Debug.Print title & vbCrLf 'put to next line
For Each key In genreCount.keys
Debug.Print key & " : " & genreCount(key)
Next key
End Function
Public Function FindMax(ByVal genreCount As Object) As String
Dim maxValue As Long
Dim maxGenre As String
Dim key As Variant
For Each key In genreCount.keys
If genreCount(key) > maxValue Then
maxValue = genreCount(key)
maxGenre = key
End If
Next key
Debug.Print vbNewLine & "Max genre is " & maxGenre & " with " & maxValue
End Function
Input and output:
Input:
Output: