IsArrayEmpty

[gcue]

Check if an array is empty.  Feedback welcome

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$iArray = Get_2d_Array()
;~ $iArray = Get_1d_Array()

$empty = IsArrayEmpty($iArray)

If $empty = 0 Then
    MsgBox(0, "", "Array is not empty")
Else
    MsgBox(0, "", "Array is empty")
EndIf

Func Get_2d_Array()

    Local $array[2][3]

    $array[0][0] = "2"
    $array[0][1] = ""
    $array[0][2] = ""

    $array[1][0] = ""
    $array[1][1] = ""
    $array[1][2] = ""

    Return $array

EndFunc   ;==>Get_2d_Array

Func Get_1d_Array()

    Local $array[3]

    $array[0] = "2"
    $array[1] = ""
    $array[2] = ""

    Return $array

EndFunc   ;==>Get_1d_Array

Func IsArrayEmpty($array)

    $string = _ArrayToString($array)

    $string = StringStripWS($string, 8)
    $string = StringReplace($string, "|", "")

    If $string = "" Then
        Return 1
    Else
        Return 0
    EndIf

EndFunc   ;==>IsArrayEmpty

 

[Andreik]

Based on the fact that _ArrayToString() already traverse the entire array to form the string it would be more practical to return false when the first index of array with some data it's encountered. I think it might be faster also but didn't check.

#include <Array.au3>

Local $aData[] = ['', '  ', ' test ', '']

MsgBox(0, '', IsArrayEmpty($aData))

Func IsArrayEmpty(Const ByRef $aArray)
    For $Index = 0 To UBound($aArray) - 1
        If Not StringIsSpace($aArray[$Index]) Then Return False
    Next
    Return True
EndFunc

or

Func IsArrayEmpty(Const ByRef $aArray)
    For $Index = 0 To UBound($aArray) - 1
        If StringIsSpace($aArray[$Index]) Then ContinueLoop
        Return False
    Next
    Return True
EndFunc

 

Edited May 14 by Andreik

[jchd]

It all depends on what you call empty.

Local $a[5] is NOT an empty array: it's an array having 5 rows, each having an empty string (or 0) as content.

Local $a[0] IS an empty array, just like $a[0][3] is empty as well.

If you consider a Map, then Local $m[] is an empty map.

Edited May 14 by jchd

[Numeric1]

Here's a complete and robust code to check the content of arrays with a maximum dimension of 10

 

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Func IsArrayEmpty(ByRef $aArray, $vEmptyValue = "")

    If Not IsArray($aArray) Then Return SetError(1, 0, Null)

    Local $iDimension = UBound($aArray, 0)
    Switch $iDimension
        Case 1
            For $i = 0 To UBound($aArray) - 1
                If _NotEmpty($aArray[$i], $vEmptyValue) Then Return False
            Next
            Return True
        Case 2
            For $i = 0 To UBound($aArray) - 1
                For $j = 0 To UBound($aArray, 2) - 1
                    If _NotEmpty($aArray[$i][$j], $vEmptyValue) Then Return False
                Next
            Next
            Return True
        Case 3
            For $i = 0 To UBound($aArray) - 1
                For $j = 0 To UBound($aArray, 2) - 1
                    For $k = 0 To UBound($aArray, 3) - 1
                        If _NotEmpty($aArray[$i][$j][$k], $vEmptyValue) Then Return False
                    Next
                Next
            Next
            Return True
        Case 4
            For $i = 0 To UBound($aArray) - 1
                For $j = 0 To UBound($aArray, 2) - 1
                    For $k = 0 To UBound($aArray, 3) - 1
                        For $l = 0 To UBound($aArray, 4) - 1
                            If _NotEmpty($aArray[$i][$j][$k][$l], $vEmptyValue) Then Return False
                        Next
                    Next
                Next
            Next
            Return True
        Case 5
            For $i = 0 To UBound($aArray) - 1
                For $j = 0 To UBound($aArray, 2) - 1
                    For $k = 0 To UBound($aArray, 3) - 1
                        For $l = 0 To UBound($aArray, 4) - 1
                            For $m = 0 To UBound($aArray, 5) - 1
                                If _NotEmpty($aArray[$i][$j][$k][$l][$m], $vEmptyValue) Then Return False
                            Next
                        Next
                    Next
                Next
            Next
            Return True
        Case 6
            For $i = 0 To UBound($aArray) - 1
                For $j = 0 To UBound($aArray, 2) - 1
                    For $k = 0 To UBound($aArray, 3) - 1
                        For $l = 0 To UBound($aArray, 4) - 1
                            For $m = 0 To UBound($aArray, 5) - 1
                                For $n = 0 To UBound($aArray, 6) - 1
                                    If _NotEmpty($aArray[$i][$j][$k][$l][$m][$n], $vEmptyValue) Then Return False
                                Next
                            Next
                        Next
                    Next
                Next
            Next
            Return True
        Case 7
            For $i = 0 To UBound($aArray) - 1
                For $j = 0 To UBound($aArray, 2) - 1
                    For $k = 0 To UBound($aArray, 3) - 1
                        For $l = 0 To UBound($aArray, 4) - 1
                            For $m = 0 To UBound($aArray, 5) - 1
                                For $n = 0 To UBound($aArray, 6) - 1
                                    For $o = 0 To UBound($aArray, 7) - 1
                                        If _NotEmpty($aArray[$i][$j][$k][$l][$m][$n][$o], $vEmptyValue) Then Return False
                                    Next
                                Next
                            Next
                        Next
                    Next
                Next
            Next
            Return True
        Case 8
            For $i = 0 To UBound($aArray) - 1
                For $j = 0 To UBound($aArray, 2) - 1
                    For $k = 0 To UBound($aArray, 3) - 1
                        For $l = 0 To UBound($aArray, 4) - 1
                            For $m = 0 To UBound($aArray, 5) - 1
                                For $n = 0 To UBound($aArray, 6) - 1
                                    For $o = 0 To UBound($aArray, 7) - 1
                                        For $p = 0 To UBound($aArray, 8) - 1
                                            If _NotEmpty($aArray[$i][$j][$k][$l][$m][$n][$o][$p], $vEmptyValue) Then Return False
                                        Next
                                    Next
                                Next
                            Next
                        Next
                    Next
                Next
            Next
            Return True
        Case 9
            For $i = 0 To UBound($aArray) - 1
                For $j = 0 To UBound($aArray, 2) - 1
                    For $k = 0 To UBound($aArray, 3) - 1
                        For $l = 0 To UBound($aArray, 4) - 1
                            For $m = 0 To UBound($aArray, 5) - 1
                                For $n = 0 To UBound($aArray, 6) - 1
                                    For $o = 0 To UBound($aArray, 7) - 1
                                        For $p = 0 To UBound($aArray, 8) - 1
                                            For $q = 0 To UBound($aArray, 9) - 1
                                                If _NotEmpty($aArray[$i][$j][$k][$l][$m][$n][$o][$p][$q], $vEmptyValue) Then Return False
                                            Next
                                        Next
                                    Next
                                Next
                            Next
                        Next
                    Next
                Next
            Next
            Return True
        Case 10
            For $i = 0 To UBound($aArray) - 1
                For $j = 0 To UBound($aArray, 2) - 1
                    For $k = 0 To UBound($aArray, 3) - 1
                        For $l = 0 To UBound($aArray, 4) - 1
                            For $m = 0 To UBound($aArray, 5) - 1
                                For $n = 0 To UBound($aArray, 6) - 1
                                    For $o = 0 To UBound($aArray, 7) - 1
                                        For $p = 0 To UBound($aArray, 8) - 1
                                            For $q = 0 To UBound($aArray, 9) - 1
                                                For $r = 0 To UBound($aArray, 10) - 1
                                                    If _NotEmpty($aArray[$i][$j][$k][$l][$m][$n][$o][$p][$q][$r], $vEmptyValue) Then Return False
                                                Next
                                            Next
                                        Next
                                    Next
                                Next
                            Next
                        Next
                    Next
                Next
            Next
            Return True
        Case Else
            Return SetError(3, 0, Null)
    EndSwitch
    Return True
EndFunc   ;==>IsArrayEmpty

Func _NotEmpty($vData, $vEmptyValue = "")
    If $vData <> $vEmptyValue Then Return True
    Return False
EndFunc   ;==>_NotEmpty

 

[Numeric1]

Local $aExampleArray[2][3][4] = [[[0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0]], [[0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0]]]
Local $aExampleArray1[2][3][4] = [[["", "", "", ""], ["", "", "", ""], ["", "", "", ""]], [["", "", "", ""], ["", "", "", ""], ["", "", "", ""]]]

ConsoleWrite("Is aExampleArray empty with 0 as empty value? " & IsArrayEmpty($aExampleArray, 0) & @CRLF)
ConsoleWrite("Is aExampleArray1 empty with empty string as empty value? " & IsArrayEmpty($aExampleArray1, "") & @CRLF)

 

[Gianni]

In this topic from some time ago (https://www.autoitscript.com/forum/topic/180468-traversing-array/), we were basically discussing how to traverse all the elements of a generic array whose dimensions are unknown. Well in the last post of that thread I posted a way to achieve that.
Using that function can save "a few" bytes and shorten the function considerably.
You can pass multidimensional arrays and even arrays that contain nested arrays without any problems.
I coded the logic whether to consider an element empty or not empty in the function itself on line 30 of the listing rather than passing it via parameter so as to be able to better customize the criterion.

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Func IsArrayEmpty(ByRef $aMyArray)
    If Not IsArray($aMyArray) Then Return SetError(1, 0, -1)
    Local $iDimensions = UBound($aMyArray, 0)
    Local $sArraySubscript = "$aMyArray"
    For $i = 0 To $iDimensions - 1
        $sArraySubscript &= '[$aLoops[' & $i & '][2]]'
    Next
    Local $aLoops[$iDimensions][3]
    For $i = 0 To $iDimensions - 1
        $aLoops[$i][0] = 0
        $aLoops[$i][1] = UBound($aMyArray, $i + 1) - 1
        $aLoops[$i][2] = $aLoops[$i][0]
    Next
    Local $x, $vContent
    Do
        $vContent = Execute($sArraySubscript)

        If IsArray($vContent) Then
            $IsEmpty = IsArrayEmpty($vContent) ; <-- recursive call for nested arrays
        Else
            ; check out your "voidness" logic here
            ; ------------------------------------
            $IsEmpty = ($vContent = '') Or ($vContent = False) Or ($vContent = Null) ; ...... up to you decide
        EndIf

        If Not $IsEmpty Then Return False ; Is not Empty

        $x = UBound($aLoops) - 1
        $aLoops[$x][2] += 1
        While ($aLoops[$x][2] > $aLoops[$x][1])
            $aLoops[$x][2] = $aLoops[$x][0]
            $x -= 1
            If $x < 0 Then ExitLoop
            $aLoops[$x][2] += 1
        WEnd
    Until $x < 0

    Return True ; Is Empty
EndFunc   ;==>IsArrayEmpty

 

Edited May 19 by Gianni

[Nine]

@Gianni  Very clever code you made there.  I was not aware of it, thank you for sharing.

I had a bit of a hard time understanding the behavior of $x.  So I changed it (hope you don't mind ) to make it, IMO, easier to read.

Func IsArrayEmpty(ByRef $aMyArray)
    If Not IsArray($aMyArray) Then Return SetError(1, 0, -1)
    Local $iDimensions = UBound($aMyArray, 0)
    Local $sArraySubscript = "$aMyArray"
    For $i = 0 To $iDimensions - 1
        $sArraySubscript &= '[$aLoops[' & $i & '][1]]'
    Next
    Local $aLoops[$iDimensions][2]
    For $i = 0 To $iDimensions - 1
        $aLoops[$i][0] = UBound($aMyArray, $i + 1)
        $aLoops[$i][1] = 0
    Next
    Local $vContent, $IsEmpty
    Do
        $vContent = Execute($sArraySubscript)

        If IsArray($vContent) Then
            $IsEmpty = IsArrayEmpty($vContent) ; <-- recursive call for nested arrays
        Else
            ; check out your "voidness" logic here
            ; ------------------------------------
            $IsEmpty = (Not $vContent) ; ...... up to you decide
        EndIf

        If Not $IsEmpty Then Return False ; Is not Empty

        For $i = 0 To $iDimensions - 1
          $aLoops[$i][1] = Mod($aLoops[$i][1] + 1, $aLoops[$i][0])
          If $aLoops[$i][1] Then ExitLoop
        Next
    Until $i = $iDimensions
    Return True ; Is Empty
EndFunc   ;==>IsArrayEmpty

 

Edited May 19 by Nine

[jguinch]

Another one : 

Func IsArrayEmpty($aArray)
    Local $iIndex, $iCount = 1, $sArray
    Local $iDimensions = UBound($aArray, 0)
    If @error Then Return SetError(1, 0, 0)
    For $i = 1 To $iDimensions
        $iCount *= UBound($aArray, $i)
    Next
    Local $iStep = $iCount, $iLastStep = $iCount
    For $i = 1 To $iDimensions
        If $i > 1 Then $iLastStep = $iStep
        $iStep /= UBound($aArray, $i)
        $iIndex = -1
        $sArray = ""
        For $j = 0 To $iCount - 1
            $iIndex += 1
            If $iIndex = $iLastStep Then $iIndex = 0
            $sArray &= "[" & Int($iIndex/$iStep) & "]"
            If $i = $iDimensions Then
                If Execute("$aArray" & $sArray) <> "" Then Return 0
            EndIf
        Next
    Next
    Return 1
EndFunc

 

[Gianni]

On 5/19/2024 at 7:27 PM, Nine said:

@Gianni  Very clever code you made there.  I was not aware of it, thank you for sharing.Hi

I had a bit of a hard time understanding the behavior of $x.  So I changed it (hope you don't mind ) to make it, IMO, easier to read.

Hi @Nine

Thanks for simplifying the code.
My "reduction" was just a quick adaptation of more complicated code intended to simulate nested For-Next loops with the ability to set the initial value of each loop, different step values both positive and negative for each nesting... just like the real For -next loops. (for those interested and needing to use it, the complete code for the For-Next simulator can be found here: https://www.autoitscript.com/forum/topic/180468-traversing-array/?do=findComment&comment=1296451 )

The adaptation used here, as well as your optimization, only allows simpler loops but which for this use case are optimal.

[Gianni]

On 5/21/2024 at 10:02 AM, jguinch said:

Another one : 

Func IsArrayEmpty($aArray)
    Local $iIndex, $iCount = 1, $sArray
    Local $iDimensions = UBound($aArray, 0)
    If @error Then Return SetError(1, 0, 0)
    For $i = 1 To $iDimensions
        $iCount *= UBound($aArray, $i)
    Next
    Local $iStep = $iCount, $iLastStep = $iCount
    For $i = 1 To $iDimensions
        If $i > 1 Then $iLastStep = $iStep
        $iStep /= UBound($aArray, $i)
        $iIndex = -1
        $sArray = ""
        For $j = 0 To $iCount - 1
            $iIndex += 1
            If $iIndex = $iLastStep Then $iIndex = 0
            $sArray &= "[" & Int($iIndex/$iStep) & "]"
            If $i = $iDimensions Then
                If Execute("$aArray" & $sArray) <> "" Then Return 0
            EndIf
        Next
    Next
    Return 1
EndFunc

 

Hi @jguinch

Looks like the list needs some fixing. Also it wasn't designed to accept nested arrays, right?

[jguinch]

@Gianni : Not, it was not designed for nested arrays. Like you said,  "up to you decide" 😀