abs

     Calculate absolute value. Abs returns the absolute value of a negative or positive variable. It does this by removing a negative sign, if found. The result of the function has the same type as its argument, which can be any numerical type.

     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 a string '-1.23' will work find. Always, abs converts the variants to an extended floating point of number prior to removing any negative sign, even if the result is an interger value.

     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.

Example

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

begin
  floatvar := -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!

  Writeln('Abs(floatvar) = ',Abs(floatvar));
  Writeln('Abs(bigFloat) = ',Abs(bigFloat));
  Writeln('Abs(int) = ',Abs(int));

  // Variants are converted into Extended floating types
  floatvar := Abs(varVar);
  Writeln('Abs(varVar) = ',floatvar);
end.

Output

Abs(floatvar) =  1.5000000000000000E+0000
Abs(bigFloat) =                      +Inf
Abs(int) = 7
Abs(varVar) =  9.800000000E+01

See Also

Div, Mod, Round, Trunc.

Brian Ellixson
FreePascal User