Re: operation of 'round' function

[maierh]

ronan.waide@euroconex.com (Ronan Waide) writes:

> This may be a bug, or may simply be a failure of understanding on my
> part. However.
> 
> GNU Emacs 20.7.1 (i386-redhat-linux-gnu, X toolkit) of Mon Jul 30 2001
> on stripples.devel.redhat.com
> 
> (round 0.5) = 0
> (round 1.5) = 2
> (round 2.5) = 2
> (round 3.5) = 4
> (round 4.5) = 4
> 

FYI. The mingw NT emacs (GNU Emacs 21.1.90.1 (i386-mingw-nt5.0.2195))
produces the following output:

(round 0.5) = 1
(round 1.5) = 2
(round 2.5) = 3
(round 3.5) = 4
(round 4.5) = 5

Harald


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maierh@myself.com wrote:

> ronan.waide@euroconex.com (Ronan Waide) writes:
>
> > (round 0.5) = 0
> > (round 1.5) = 2
> > (round 2.5) = 2
> > (round 3.5) = 4
> > (round 4.5) = 4
>
> FYI. The mingw NT emacs (GNU Emacs 21.1.90.1
> (i386-mingw-nt5.0.2195)) produces the following output:
>
> (round 0.5) = 1
> (round 1.5) = 2
> (round 2.5) = 3
> (round 3.5) = 4
> (round 4.5) = 5

I guess this proves the often-cited text in the Perl
documentation.  It is equally true for Emacs.

    Rounding in financial applications can have seri-
    ous implications, and the rounding method used
    should be specified precisely.  In these cases, it
    probably pays not to trust whichever system round-
    ing is being used by Perl, but to instead imple-
    ment the rounding function you need yourself.

Peter

-- 
I put the batteries the wrong way in my flashlight.
Now when I turn it on, it gets dark.