We help IT Professionals succeed at work.
Get Started

Quicksort for multiple columns in excel vba userform

Last Modified: 2008-01-09
I have a multicolumn listbox that I want to have the option of sorting any of the 7 columns. I would use the bubblesort, but there can be potentially 35000 in the list which makes it kind of slow. I found the code below for quicksort, but I am not sure how I can modify it so that I can sort multiple columns, not just one. Can anyone help me?

Sub Quicksort (List() As Long, min As Integer, max As Integer)
Dim med_value As Long
Dim hi As Integer
Dim lo As Integer
Dim i As Integer

    ' If the list has no more than 1 element, it's sorted.
    If min >= max Then Exit Sub

    ' Pick a dividing item.
    i = Int((max - min + 1) * Rnd + min)
    med_value = List(i)

    ' Swap it to the front so we can find it easily.
    List(i) = List(min)

    ' Move the items smaller than this into the left
    ' half of the list. Move the others into the right.
    lo = min
    hi = max
        ' Look down from hi for a value < med_value.
        Do While List(hi) >= med_value
            hi = hi - 1
            If hi <= lo Then Exit Do
        If hi <= lo Then
            List(lo) = med_value
            Exit Do
        End If

        ' Swap the lo and hi values.
        List(lo) = List(hi)
        ' Look up from lo for a value >= med_value.
        lo = lo + 1
        Do While List(lo) < med_value
            lo = lo + 1
            If lo >= hi Then Exit Do
        If lo >= hi Then
            lo = hi
            List(hi) = med_value
            Exit Do
        End If

        ' Swap the lo and hi values.
        List(hi) = List(lo)

    ' Sort the two sublists
    Quicksort List(), min, lo - 1
    Quicksort List(), lo + 1, max
End Sub
Watch Question
This problem has been solved!
Unlock 1 Answer and 19 Comments.
See Answer
Why Experts Exchange?

Experts Exchange always has the answer, or at the least points me in the correct direction! It is like having another employee that is extremely experienced.

Jim Murphy
Programmer at Smart IT Solutions

When asked, what has been your best career decision?

Deciding to stick with EE.

Mohamed Asif
Technical Department Head

Being involved with EE helped me to grow personally and professionally.

Carl Webster
CTP, Sr Infrastructure Consultant
Ask ANY Question

Connect with Certified Experts to gain insight and support on specific technology challenges including:

  • Troubleshooting
  • Research
  • Professional Opinions
Did You Know?

We've partnered with two important charities to provide clean water and computer science education to those who need it most. READ MORE