Node:Abs, Next:absolute, Up:Reference

### Abs

#### Synopsis

    function Abs (i: integer_type): integer_type;

or

    function Abs (x: real_type): real_type;

or

    function Abs (z: complex_type): real_type;

#### Description

Returns the absolute value of the argument. For integer or real values of `x`, the definition is

    function Abs (x: integer_or_real_type): integer_or_real_type;
    begin
      if x < 0 then
        Abs := -x
      else
        Abs := x
    end;

whereas for complex values it is

    function Abs (x: Complex): Real;
    begin
      Abs := SqRt (x * Conjugate (x))
    end;

#### Conforming to

The function `Abs` is defined in ISO 7185 Pascal; its application to complex values is defined in ISO 10206 Extended Pascal.

#### Example

    program AbsDemo;
    var
      i1: Complex;
    begin
      WriteLn (Abs (42));             { 42 }
      WriteLn (Abs (-42));            { 42 }
      WriteLn (Abs (-12.1) : 0 : 1);  { 12.1 }
      i1 := Cmplx (1, 1);             { 1 + i }
      WriteLn (Abs (i1) : 0 : 3)      { 1.414, i.e. SqRt (2) }
    end.

#### See also

Sqr.