Re: Odd math

From: Dennis M. Heisler <dheisler_at_binghamton.edu>
Date: Wed, 12 Jul 2000 07:00:10 -0400
Message-Id: <10556.111779@fatcity.com>

On 7.3.4

SQL> select 2 - log(2,4) from dual;

2-LOG(2,4)

---

 2.000E-38

SQL> select trunc(round(log(2,4),38)) from dual

TRUNC(ROUND(LOG(2,4),38))

---

                        1

SQL> select trunc(round(log(2,4),37)) from dual;

TRUNC(ROUND(LOG(2,4),37))

---

                        2

Dennis

"A. Bardeen" wrote:

> Steve,
>
> It's an old bug. The workaround is to round the
> number to a precision of 38 before truncating it:
>
> SQLWKS> select trunc(round(log(2,4),38)) from dual;
> TRUNC(ROUN
> ----------
> 1
>
> HTH,
>
> -- Anita
>
> --- Steve Adams <steve.adams_at_ixora.com.au> wrote:
> > Hi All,
> >
> > Oracle 8.1.6 appears to think that ... trunc(log(2,
> > 4)) = 1.
> >
> > SQL> select trunc(log(2,4)) from dual;
> >
> > TRUNC(LOG(2,4))
> > ---------------
> > 1
> >
> > Does it reproduce on earlier versions?
> >
> > Regards,
> > Steve Adams
> > http://www.ixora.com.au/
> > http://www.oreilly.com/catalog/orinternals/
> > http://www.christianity.net.au/
> >
> > --
> > Author: Steve Adams
> > INET: steve.adams_at_ixora.com.au
> >
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Received on Wed Jul 12 2000 - 06:00:10 CDT