AutoIt UDF to perform actions on decimals numbers

; ==> _RoundDecimal($NbDouble, $NbForRound)
; This function takes two parameters:
; $NbDouble to take the number to be rounded. Datatype is double.
; $NbForRound to contain the precision of the rounding. Datatype is int
; This function return a variable of datatype double or int if rounding is zero or an @error code.
; @error:
;   1 => $NbDouble isn't number
;   2 => $NbForRound isn't integer
;   3 => $NbForRound ins't positive number.
Func _RoundDecimal($NbDouble, $NbForRound)
    ;   If $NbDouble isn't double datatype.
    If IsFloat($NbDouble) <> 1 Then
        If IsNumber($NbDouble) = 1 Then
            Return $NbDouble
        Else
            SetError(1)
            Return
        EndIf
    EndIf

    ;   If $NbToRound isn't integer datatype.
    If IsInt($NbForRound) <> 1 Then
        SetError(2)
        Return
    EndIf

    ; If $NbToRound isn't a  positive number
    If $NbForRound <= 0 Then
        SetError(3)
        Return
    EndIf

    ;   We transform $NbDouble in string to separate iteger part to decimal part
    Local $StringNbDouble = String($NbDouble)
    $StringNbDouble = StringSplit($StringNbDouble,".")

    Local $LenghtOfDoublePart = StringLen($StringNbDouble[2])

    ;   If the number of char to keep is greater than the real lenght of string.
    If $NbForRound >= $LenghtOfDoublePart Then
        Return $NbDouble
    EndIf

    $StringNbDouble[2] = StringLeft($StringNbDouble[2], $NbForRound)
    Local $Result = Number($StringNbDouble[1] & "." & $StringNbDouble[2])
    Return $Result
Return
EndFunc
; <== _RoundDecimal($NbDouble, $NbForRound)



; ==> _NbAfterDecimalPoint($NbDouble)
; This function takes one parameter:
; $NbDouble to take the number to be rounded. Datatype is double.
; This function return a variable of datatype int and contain the number of number after decimal point.
; @error:
;   1 => $NbDouble isn't number
Func _NbAfterDecimalPoint($NbDouble)
    If IsFloat($NbDouble) <> 1 Then
        If IsNumber($NbDouble) = 1 Then
            Return $NbDouble
        Else
            SetError(1)
            Return
        EndIf
    EndIf

    Local $StringNbDouble = String($NbDouble)
    $StringNbDouble = StringSplit($StringNbDouble,".")
    Local $LenghtOfDoublePart = StringLen($StringNbDouble[2])
    Return Int($LenghtOfDoublePart)
EndFunc
; <== _NbAfterDecimalPoint($NbDouble)