Bubblesort

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Philosophaie

Is there a command called Bubblesort? If so what can it do and its functions
like multiple rows, sort a range by ascendind or descending.
 
"Bubblesort" is a relatively simple algorithm for sorting an array with
code. There's no command for it, you need to roll your own (search this
group for examples).

If you want to sort a range of cells use Excel's sort, record a macro to get
the syntax and see "sort" in VBA help.

Regards,
Peter T
 
I don't think there's a command in excel.

It's a generic term for a way of sorting a list - compare item 1 to item 2,
if they're back to front then reverse the order. Compare item 2 to item 3,
then item 3 to item 4 etc.

You keep going through from item 1 to item n, comparing pairs, until you can
go from 1 to n without swapping any over. It's not a very efficient way of
sorting but is easy to code and to scale up

Sam
 
Is there a command called Bubblesort? If so what can it do and its functions
like multiple rows, sort a range by ascendind or descending.
Click to expand...

John Walkenbach's "Excel 2003 Power Programming with VBA" (and
probably the 2007 version as well) has an interesting table comparing
various sorting algorithms. As an example of the sort of inefficiency
that Sam Wilson describes, Walkenbach ran a test where it took
bubblesort 329.24 seconds to sort a randomly generated list of 50,000
numbers but took another algorithm called quicksort only 0.27 seconds
to sort the same list. If it is ranges that you want to sort then
Peter T's suggestion of turning on the macro recorder when using
Excel's built-in Data/sort is the way to go. Even if you want to sort
VBA arrays a practical way is to first transfer the data into a
worksheet, sort it there, and transfer it back to an array. Despite
all of the data transfer going on this still outperforms boublesort
except for the smallest arrays and is almost as efficient as
quicksort. See Walkenbach for more details.

Hope that helps

-John Coleman
 
Here's a bubble sort that I used for a two dimensional array. Hope it helps.

Sub SortList(CustList)

'CustList is the 2 dimensional array passed to the Sub. It was in fact a
'list of customer account numbers and their company names

Dim Temp1 As String
Dim Temp2 As String
Dim First As Integer
Dim Last As Long
Dim i As Long
Dim j As Long

'This sub sorts the list into alphabetical order by first of the numbers in
the array
' using the bubble sort algorithm


Dim Temp


Last = UBound(CustList, 2)
For i = 1 To Last
For j = i + 1 To Last
If CustList(1, i) > CustList(1, j) Then
Temp1 = CustList(1, j)
Temp2 = CustList(2, j)
CustList(1, j) = CustList(1, i)
CustList(2, j) = CustList(2, i)
CustList(1, i) = Temp1
CustList(2, i) = Temp2
End If
Next j
Next i
End Sub

If this helps, please click Yes
 
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