# Sort Algorithm in WinWrap Basic

QAID # 17341 Published

## Question / Problem:

**Sort Algorithm in WinWrap Basic**

## Answer / Solution:

The following is an implementation of the Quick Sort algorithm purely in WinWrap Basic. It can be used to sort any type of object array. The example below sorts any array of Alternatives based on their confidence. And yes it is fast — it takes milliseconds to sort 100 items.

The concrete example below was a postprocessing of Database Locator results — where the alternative confidences where changed by script, and the alternatives needed resorting.

# Preparing CscXDocFieldAlternatives for Sorting

This code snippet shows how to prepare CscXDocFieldAlternatives for sorting, call the sort routine, and then apply the changes to CscXDocFieldAlternatives.

Type alt id As Integer conf As Double End Type Public Sub resortAlternativesByConfidence(alts As CscXDocFieldAlternatives) Dim i As Integer 'Create a list of references to alternatives to store their id and confidence. ' We will then sort the list by the confidence. Dim refs() As alt ReDim refs(alts.Count - 1) For i = 0 To alts.Count - 1 refs(i).ID = i refs(i).Conf = alts(i).Confidence Next sort(refs) 'Copy all of the resorted alternatives to the end of the Alternatives object For i = 0 To alts.Count - 1 alts.Create() altcopy(alts(refs(i).ID), alts(alts.Count - 1)) Next 'Delete all of the unsorted alternatives. For i = alts.Count / 2 - 1 To 0 Step -1 alts.Remove(i) Next End Sub '!!!!!! You MUST implement a Compare function for the sort algorithm to use. 'Here we sort based on confidence. Private Function Compare(a As Variant, b As Variant) If a.Conf > b.Conf Then Compare = True Else Compare = False End Function

# Quick Sort in WinWrap

**This is the actual generic Quick Sort routine, which uses partitioning and recursion to sort:**

Private Sub sort(ByRef a As Variant) quicksort(a, 0, UBound(a)) End Sub Sub quicksort(ByRef a As Variant, ByVal Left As Integer, ByVal Right As Integer) Dim pivot As Integer If Right > Left Then pivot = getpivot(Left, Right) pivot = partition(a, Left, Right, pivot) quicksort(a, Left, pivot) quicksort(a, pivot + 1, Right) End If End Sub Function getpivot(ByVal Left As Integer, ByVal Right As Integer) 'Return a random integer between Left and Right getpivot = (Rnd() * (Right - Left + 1) * 1000) Mod (Right - Left + 1) + Left End Function Function partition(ByRef a As Variant, ByVal Left As Integer, _ ByVal Right As Integer, ByRef pivot As Integer) Dim i Dim piv Dim store piv = a(pivot) swap(a(Right), a(pivot)) store = Left For i = Left To Right - 1 If Compare(a(i), piv) Then swap(a(store), a(i)) store = store + 1 End If Next swap(a(Right), a(store)) partition = store End Function Sub swap(ByRef v1, ByRef v2) Dim tmp As Variant tmp = v1 v1 = v2 v2 = tmp End Sub

## Applies to:

Product |
Version |
Category |
---|---|---|

AXPRO |
3.5 |
Configuration |

AXPRO |
4.0 |
Configuration |

AXPRO |
4.5 |
Configuration |

AXPRO |
5.0 |
Configuration |

AXPRO |
5.5 |
Configuration |