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> I guess that 1.000000000000000001 is non-unity
> as an 80-bit IEEE number, but rounds to 1 when
> stored as a 64-bit IEEE number.
>
> As an example try x := Math.Pi()
>
> then later try
>
> x = Math.Pi(). The answer is FALSE.
>
The constants defined in a Module are stored in REAL
precision, so the above argument does not apply.
But you are right, 1+10^(-18) is not 1 in 80 bit IEEE,
but it is 1.0 in 64 (REAL) precision.
Given the following module, the command Test.Do
prints $FALSE.
- Dominik
MODULE Test;
IMPORT StdLog, Math;
PROCEDURE OnePlusTenToThePowerOfMinusEighteen(): REAL;
BEGIN RETURN 1 + Math.IntPower(10, -18);
END OnePlusTenToThePowerOfMinusEighteen;
PROCEDURE Do*;
VAR x: REAL;
BEGIN
x := OnePlusTenToThePowerOfMinusEighteen();
StdLog.Bool(x = OnePlusTenToThePowerOfMinusEighteen());
END Do;
END Test.
--------------------------------------------
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Received on Mon Feb 17 2003 - 19:31:03 UTC