;------------------------------------------------------------------------------------------------------------------------------------------
#DefineFunction udfArrayHeapSort (arrArray)
If !ArrInfo (arrArray, -1) Then Return ArrDimension (0) ; Invalid input array, return empty valid dim-0 array.
If ArrInfo (arrArray, 0) != 1 Then Return ArrDimension (0) ; Only dim-1 array allowed, return empty valid dim-0 array.
intElements = ArrInfo (arrArray, 1)
If intElements == 0 Then Return ArrDimension (0) ; Input array has no elements, return empty valid dim-0 array.
If intElements == 1 Then Return arrArray ; Input array has only one element, return the input array.

intR = intElements
intM = (intElements / 2) - 1
For intI = intM To 0 By -1
   intL = intI
   anyValue = arrArray [intL]
   While (intL < (intR / 2))
      intNext = intL + intL + 1
      If (intNext + 1) < intR Then If arrArray [intNext] < arrArray [intNext + 1] Then intNext = intNext + 1
      If anyValue >= arrArray [intNext] Then Break
      arrArray [intL] = arrArray [intNext]
      intL = intNext
   EndWhile
   arrArray [intL] = anyValue
Next

While intElements > 1
   anyValue = arrArray [0]
   arrArray [0] = arrArray [intElements - 1]
   arrArray [intElements - 1] = anyValue

   intElements = intElements - 1
   intR = intElements
   intL = 0

   anyValue = arrArray [intL]
   While intL < (intR / 2)
      intNext = intL + intL + 1
      If (intNext + 1) < intR Then If arrArray [intNext] < arrArray [intNext + 1] Then intNext = intNext + 1
      If anyValue >= arrArray [intNext] Then Break
      arrArray [intL] = arrArray [intNext]
      intL = intNext
   EndWhile
   arrArray [intL] = anyValue
EndWhile

Return arrArray
;..........................................................................................................................................
; Heapsort algorithm adapted from:
; 'Algorithmen und Datenstrukturen, Prof. Dr. Gerald Timmer, 1998-11-06, Fachhochschule Osnabrück'.
; Reference: 'http://gtsun.et.fh-osnabrueck.de/lehre/algorithmen/alds-skript/node20.html'.
;
; Detlev Dalitz.20020822
;..........................................................................................................................................
#EndFunction
;------------------------------------------------------------------------------------------------------------------------------------------

;----------------------------------------------------------------------------------------------------------------------
#DefineFunction udfArrayItemize (arrArray, strDelimiter)
If !ArrInfo (arrArray, -1) Then Return "" ; No array.
If !ArrInfo (arrArray, 6) Then Return "" ; No elements.
If ArrInfo (arrArray, 0) > 1 Then Return "" ; Too much dimensions.
strItemList = ""
intHigh = Max (ArrInfo (arrArray, 1) - 1, 0)
intLow = 0
For intElem = intLow To intHigh
   If !!VarType (arrArray [intElem])
      strItemList = ItemInsert (arrArray [intElem], -1, strItemList, strDelimiter)
   Else
      strItemList = ItemInsert ("", -1, strItemList, strDelimiter)
   EndIf
Next
Return strItemList
;----------------------------------------------------------------------------------------------------------------------
; This UDF "udfArrayItemize" converts a given dim-1 array into an itemlist
; with each item separated by delimiter character.
;
; Example: strMyItemList = udfArrayItemize (arrMyArray, @TAB)
; Creates an itemList from array.
;
; Note:
; This UDF supports only dim-1 array.
; An array element which is not initialized has a Vartype=0 (undefined).
; Therefore an empty item will be appended to target itemlist.
;
; Detlev Dalitz.20020718.20090508.
;----------------------------------------------------------------------------------------------------------------------
#EndFunction
;----------------------------------------------------------------------------------------------------------------------


; Test.

strMsgTitle = "Demo: udfArrayHeapSort (arrArray)"
strMsgText = ""

strDelimiter = ","
strItemList = "22,q,w,e,r,t,T,999,a,s,d,f,1,/z,B5,-196" ; 16 Items.

arrA = Arrayize (strItemList, strDelimiter)
arrB = Arrayize (strItemList, strDelimiter)

arrB = udfArrayHeapSort (arrB)

strMsgText = strMsgText : "Array A: " : @LF : udfArrayItemize (arrA, strDelimiter) : @LF : @LF ; "22,q,w,e,r,t,T,999,a,s,d,f,1,/z,B5,-196"
strMsgText = strMsgText : "Array B sorted: " : @LF : udfArrayItemize (arrB, strDelimiter) : @LF : @LF ; "/z,-196,1,22,999,a,B5,d,e,f,q,r,s,t,T,w"

Message (strMsgTitle, strMsgText)

Exit