Delphi Basics : Abs command

DelphiBasics

Abs
Function

Gives the absolute value of a number (-ve sign is removed)

System unit

function Abs(Number Numeric type):Numeric type;

Description

The Abs function returns the absolute value of a negative or positive number. It does this by removing a negative sign, if found.

The Number can be any numeric type, and can even be a Variant, as long as it can be converted to a number. For example, a Variant set to a string '-1.23' will work fine. Always, Abs converts the Variant to an Extended floating point number prior to removing any negative sign, even if the result is an integer value.

Notes

Floating point numbers can be set to extreme values, such as infinity (see the example). The Abs function simply removes the negative sign of these, so that -INF becomes INF.

Related commands

Div		Performs integer division, discarding the remainder
Mod		Performs integer division, returning the remainder

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Example code : Illustrating absolute values of different data types

var
  float, bigFloat : single;
  int : Integer;
  varVar : Variant;

begin
  float    := -1.5;      // Small negative floating point number
  bigFloat := -4.56E100;  // Infinite negative floating point number
  int      := -7;        // Negative integer
  varVar   := '-98';      // Variants are converted to floating point!

  ShowMessage('Abs(float) = '+FloatToStr(Abs(float)));
  ShowMessage('Abs(bigFloat) = '+FloatToStr(Abs(bigFloat)));
  ShowMessage('Abs(int) = '+FloatToStr(Abs(int)));

  // Variants are converted into Extended floating types
  float := Abs(varVar);
  ShowMessage('Abs(varVar) = '+FloatToStr(float));
end;

Show full unit code

  Abs(float) = 1.5
  Abs(bigFloat) = INF
  Abs(int) = 7
  Abs(varVar) = 98