Node:Abs, Next:absolute, Up:Reference
function Abs (i: integer_type): integer_type;or
function Abs (x: real_type): real_type;or
function Abs (z: complex_type): real_type;
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;
The function Abs is defined in ISO 7185 Pascal; its
application to complex values is defined in ISO 10206 Extended
Pascal.
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.