Fabio,

>The problem it not this.

Yes, it is. You seem to not understand the floating point binary representation and how it is converted to decimal display.

It goes back to your thread from a few weeks ago complaining about very small numbers not being equal to 0.

It works as expected if you SET FIXED OFF. Because the difference between your two datetimes is exactly 3960 not 3959.999965131283.

You setting a memvar to a value of 3959.999965131283 is not necessarily the exact same bit pattern as what a independent calculation will result in. It's like expecting the lines of code below to print .T.

x = 0.333333333333
y = 1.0 / 3.0
? x = y

when they are in fact not the same value.


>To me it does not interest the value of lnDiff, it origin, ....
>
>My interest is this:
>
>

>i have two variable, equal value, equal type, apply a deterministic
>function and get a not deterministic result !
>

>
>Any programming enviroment that do this is bad.