Abs Function

Returns the absolute value of a number.

Syntax

Abs(number)

Parts

• number: Required. Any valid numeric expression. If number contains Null, Null is returned; if it is an uninitialized variable, zero is returned.

Return Value

The return type is the same as the input type, except: - If number is a Variant containing Null, returns Null - If number is an uninitialized Variant, returns 0 - The absolute value is always non-negative (>= 0)

Remarks

• Absolute Value: The absolute value of a number is its unsigned magnitude. For example, Abs(-1) and Abs(1) both return 1.
• Type Preservation: The return type matches the input type. If you pass an Integer, you get an Integer back. If you pass a Double, you get a Double back.
• Null Handling: If the argument is Null, the function returns Null.
• Overflow: For the most negative value of Integer (-32768) or Long (-2147483648), Abs will cause an overflow error because the positive equivalent is outside the valid range.
• Performance: Abs is highly optimized and very fast for numeric operations.

Examples

Basic Usage

Dim result As Integer
result = Abs(-50)
' result = 50

With Positive Numbers

Dim value As Integer
value = Abs(25)
' value = 25 (unchanged)

With Floating Point

Dim distance As Double
distance = Abs(-12.75)
' distance = 12.75

With Zero

Dim zero As Integer
zero = Abs(0)
' zero = 0

With Expressions

Dim x As Integer, y As Integer
x = 10
y = 20
Dim difference As Integer
difference = Abs(x - y)
' difference = 10

Calculating Distance

Function Distance(x1 As Double, y1 As Double, x2 As Double, y2 As Double) As Double
Distance = Sqr((x2 - x1) ^ 2 + (y2 - y1) ^ 2)
End Function

' Often used with Abs for 1D distance:
Dim dist As Double
dist = Abs(x2 - x1)

With Currency

Dim amount As Currency
amount = Abs(-1234.56@)
' amount = 1234.56

With Variants

Dim v As Variant
v = -42
Dim result As Variant
result = Abs(v)
' result = 42

Common Patterns

Ensuring Positive Values

Sub ProcessValue(ByVal input As Integer)
Dim positiveInput As Integer
positiveInput = Abs(input)
' Always work with positive values
DoSomething positiveInput
End Sub

Calculating Difference

Function GetDifference(a As Long, b As Long) As Long
GetDifference = Abs(a - b)
End Function

Data Validation

Function IsWithinTolerance(actual As Double, expected As Double, tolerance As Double) As Boolean
IsWithinTolerance = (Abs(actual - expected) <= tolerance)
End Function

Financial Calculations

Function CalculateVariance(actual As Currency, budget As Currency) As Currency
CalculateVariance = Abs(actual - budget)
End Function

Array Processing

Sub MakeArrayPositive(arr() As Integer)
Dim i As Integer
For i = LBound(arr) To UBound(arr)
arr(i) = Abs(arr(i))
Next i
End Sub

Comparison Logic

Function MaxAbsValue(a As Double, b As Double) As Double
If Abs(a) > Abs(b) Then
MaxAbsValue = Abs(a)
Else
MaxAbsValue = Abs(b)
End If
End Function

Coordinate Systems

Function ManhattanDistance(x1 As Integer, y1 As Integer, x2 As Integer, y2 As Integer) As Integer
ManhattanDistance = Abs(x2 - x1) + Abs(y2 - y1)
End Function

Related Functions

• Sgn: Returns the sign of a number (-1, 0, or 1)
• Fix: Returns the integer portion of a number (truncates toward zero)
• Int: Returns the integer portion of a number (rounds down)
• Round: Rounds a number to a specified number of decimal places

Type Compatibility

Performance Notes

• Abs is a very fast intrinsic function
• No function call overhead in compiled code
• Optimized to CPU instructions where possible
• Prefer Abs over manual If/Then checks for performance

Abs is parsed as a regular function call (CallExpression) This module serves as documentation and reference for the Abs function