Help Determining This Sort Algorithm

Question

I came across this sort algorithm when looking for a function to sort a collection of objects in VBA by a property of the object. In order to make sure that I understand all aspects of the code that I implement, I wanted to validate my thoughts on this algorithm. To me it looks like an Insertion Sort, but I wanted to check with the community to make sure that I was correct.

To help myself understand it better, I put together this pseudocode of what I believe that the function is doing. (Just assume it will be sorted in ascending order)

UnknownSort(collection C)
    for i=1 to C.Count - 1
      begin
        x = C[i].Value
        index = i
        for j=i+1 to C.Count 
         begin
          y = C[j].Value
          if x > y then
            x = y
            index = j
          j++
         end
      if index <> i then
        temp = C[index]
        C.Remove(index)
        C.Add temp before C[i]
      i = i + 1
    end

I have included the code as well in case I made a mistake in the pseudocode above.

For those not familiar with VBA, the col.Add obj, , i inserts the object into the collection before the object i in the collection.

Private Function SortCollection(col As Collection, psSortPropertyName As String, pbAscending As Boolean) As Collection

Dim obj As Object
Dim i As Integer
Dim j As Integer
Dim iMinMaxIndex As Integer
Dim vMinMax As Variant
Dim vValue As Variant
Dim bSortCondition As Boolean
Dim bUseKey As Boolean
Dim sKey As String        

    For i = 1 To col.Count - 1
        Set obj = col(i)
        vMinMax = CallByName(obj, psSortPropertyName, VbGet)
        iMinMaxIndex = i

        For j = i + 1 To col.Count
            Set obj = col(j)
            vValue = CallByName(obj, psSortPropertyName, VbGet)

            If (pbAscending) Then
                bSortCondition = (vValue < vMinMax)
            Else
                bSortCondition = (vValue > vMinMax)
            End If

            If (bSortCondition) Then
                vMinMax = vValue
                iMinMaxIndex = j
            End If

            Set obj = Nothing
        Next j

        If (iMinMaxIndex <> i) Then
            Set obj = col(iMinMaxIndex)

            col.Remove iMinMaxIndex
            col.Add obj, , i               

            Set obj = Nothing
        End If

        Set obj = Nothing
    Next i
   Set SortCollection = col
End Function

Edit For a list that will never be longer than 300 elements with a random displacment, is this algorithm ok, or should I try to implement something else?

Answer 1

I believe this is Selection sort.

Edit: To answer your question, this is not a fast algorithm it's a O(n²), but, if this is your only processing I think O(n²) for 300 elements is good.

You should probably test your whole program and then judge if you need optimization or not. Just keep in mind that your sort algorithm can be optimized.