Shrink array after deleting 1 random element

[tarretarretarre]

As the title states, if i would to "shrink" my array after deleting 1 random element, is this the most efficient/effective way i can do it? without using array.au3 UDF

 

Yes this is only for 1D arrays. Maybe 2D sometime but not for now

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#include "array.au3"
Local $MyArray[1]
$MyArray[0] = 0

add("One")
add("Two")
add("Three")
add("Four")

_ArrayDisplay($MyArray)
RemoveByElementId($MyArray, 2)
_ArrayDisplay($MyArray)
RemoveByElementId($MyArray, 2)
_ArrayDisplay($MyArray)


;Adding data to array without _ArrayAdd
Func add(ByRef $MyArray, $iData)
    $MyArray[0] += 1
    ReDim $MyArray[$MyArray[0] + 1]
    $MyArray[$MyArray[0]] = $iData
EndFunc   ;==>add

;Remove by specified ArrayID
Func RemoveByElementId(ByRef $MyArray, $ArrayID)
    If $MyArray[0] < $ArrayID Or $ArrayID == 0 Then Return False;Error out of bounds

    ;Replace the deleted Element with neighbour
    $MyArray[$ArrayID] = $MyArray[$ArrayID - 1]

    ;Shrink the array
    For $i = $ArrayID To $MyArray[0]
        $MyArray[$i - 1] = $MyArray[$i]
    Next

    ;Redim the array
    ReDim $MyArray[$MyArray[0]]
    $MyArray[0] -= 1
EndFunc   ;==>RemoveByElementId

 

[BrewManNH]

You could do it this way, which makes things a bit easier to follow. 

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#include "array.au3"
Local $MyArray[1]
$MyArray[0] = 0

add($MyArray, "One")
add($MyArray, "Two")
add($MyArray, "Three")
add($MyArray, "Four")

_ArrayDisplay($MyArray)
RemoveByElementId($MyArray, 2)
_ArrayDisplay($MyArray)
RemoveByElementId($MyArray, 2)
_ArrayDisplay($MyArray)


;Adding data to array without _ArrayAdd
Func add(ByRef $aMyArray, $iData)
    $aMyArray[0] += 1
    ReDim $aMyArray[$aMyArray[0] + 1]
    $aMyArray[$aMyArray[0]] = $iData
EndFunc   ;==>add

;Remove by specified ArrayID
Func RemoveByElementId(ByRef $aMyArray, $ArrayID)
    If Not IsArray($aMyArray) Then Return SetError(1, 0, 0)
    Local $iUbound = UBound($aMyArray)

    If $ArrayID < 0 or $ArrayID > $iUbound Then Return SetError(1, 0, 0)

    Local $aTempArray[$iUbound - 1]
    For $iLoop = 0 to $ArrayID - 1
        $aTempArray[$iLoop] = $aMyArray[$iLoop]
    Next
    For $iLoop = $ArrayID + 1 to $iUbound - 1
        $aTempArray[$iLoop - 1] = $aMyArray[$iLoop]
    Next
    $aMyArray = $aTempArray

;~  If $MyArray[0] < $ArrayID Or $ArrayID == 0 Then Return False;Error out of bounds

;~  ;Replace the deleted Element with neighbour
;~  $MyArray[$ArrayID] = $MyArray[$ArrayID - 1]

;~  ;Shrink the array
;~  For $i = $ArrayID To $MyArray[0]
;~      $MyArray[$i - 1] = $MyArray[$i]
;~  Next

;~  ;Redim the array
;~  ReDim $MyArray[$MyArray[0]]
;~  $MyArray[0] -= 1
EndFunc   ;==>RemoveByElementId

Your add() function is pretty much the same as the old _ArrayAdd without any error checking, and your RemoveByElementID would only work if the array has a count in the first (0) element.

[iamtheky]

thats twice im close to the same conclusion as bob, spooky.   I dont know if its better/worse than the OP, but it is different.

Func RemoveByElementId(ByRef $MyArray, $ArrayID)
    local $xMyArray[ubound($MyArray) - 1]
    local $x

    If $MyArray[0] < $ArrayID Or $ArrayID == 0 Then Return False;Error out of bounds

    For $i = 1 To $MyArray[0]
     $x = $i <= $ArrayID ? $i : $i - 1
     If $i <> $ArrayID Then $xMyArray[$x] = $MyArray[$x]
    Next

    $MyArray = $xMyArray
    $MyArray[0] = ubound($MyArray) - 1

EndFunc   ;==>RemoveByElementId

 

one more way, just to be even moreso: *fatally flawed - fixed in post #12

Func RemoveByElementId(ByRef $MyArray, $ArrayID)
    local $sArr = ""
    local $sRemove = $MyArray[$ArrayID]

        for $i = 1 to ubound($MyArray) - 1
            $sArr &= $MyArray[$i] & "|"
        next

    $MyArray =  stringsplit($MyArray[0] - 1 & "|" & stringreplace(stringtrimright($sArr , 1) , $sRemove & "|" ,"") , "|" , 2)

EndFunc   ;==>RemoveByElementId

Edited August 21, 2015 by boththose

[Gianni]

@boththse, Your last way could fail if unluckily some element of the array already contains the "|" character

Edited August 21, 2015 by Chimp

[water]

Or you could simply set deleted items to a specific value so that you can later ignore the item when processing the array. 

[guinness]

Like Null (the keyword).

Edited August 21, 2015 by guinness

[water]

I think of ANY character that is not part of your data. 

[guinness]

If someone is using Null as a way to denote valid data, then they're using it wrong.

I think of ANY character that is not part of your data. 

So long as they clearly document that this char or set of chars means "NO DATA". Though knowing developers hate/suck at writing documentation (first hand experience), then I doubt this happening.

[water]

Code without documentation isn't worth using it (first hand experience too).

[guinness]

Code without documentation isn't worth using it (first hand experience too).

I wish I knew this back when I needed it.

[water]

Live means learning constantly 

[iamtheky]

Your last way could fail ...

 

.. also if they would have used the last element..  still has potential issues if they choose to use pipe.

Func RemoveByElementId(ByRef $MyArray, $ArrayID)
    local $sArr = ""
    local $sRemove = $MyArray[$ArrayID]

        for $i = 1 to ubound($MyArray) - 1
            $sArr &= $MyArray[$i] & chr(0)
        next

    $MyArray = $ArrayID = ubound($MyArray) - 1 ? stringsplit($MyArray[0] - 1 & chr(0) & stringreplace($sArr , chr(0) & $sRemove & chr(0) ,"") , chr(0) , 2) : stringsplit($MyArray[0] - 1 & chr(0) & stringreplace(stringtrimright($sArr , 1) , $sRemove & chr(0) ,"") , chr(0) , 2)

EndFunc   ;==>RemoveByElementId

 

Edited August 21, 2015 by boththose