ABS Function
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 Action

 Returns the absolute value of a numeric expression.


 Syntax

  ABS( numeric-expression#)


 Remarks

 The absolute value is the unsigned magnitude of its argument. For example,
 ABS(-1) and ABS(1) are both 1.


 Example

 The following example finds an approximate value for a cube root. It uses
 ABS to find the difference between two guesses to see if the current
 guess is accurate.  DEFDBL establishes the default data type for
 all variables.

 DEFDBL A-Z
 Precision = .0000001#
 CLS                               ' Clear the screen.
 INPUT "Enter a value. ", Value    ' Prompt for input.
 ' Make the first two guesses.
 X1 = 0#. X2 = Value
 ' Loop until the difference between guesses is
 ' less than the required precision.
 DO UNTIL ABS(X1 - X2) < Precision
     X = (X1 + X2) - 2#
     ' Adjust the guesses.
     IF X * X * X - Value < 0# THEN
         X1 = X
     ELSE
         X2 = X
     END IF
 LOOP
 PRINT "The cube root is "; X


 Output

 Enter a value. 27

 The cube root is  2.99999997206032