Re: Re: [GENERAL] +/- Inf for float8's

I can't say whether its worth the trouble to add NaN, but I will say that NaN
is not the same as NULL.  NULL is missing data; NaN is 0./0.  The difference
is significant for numerical applications.

Tim

"Ross J. Reedstrom" wrote:

> Thomas -
> A general design question. There seems to be a good reason to allow +/-Inf
> in float8 columns: Tim Allen has an need for them, for example. That's
> pretty straight forward, they seem to act properly if the underlying float
> libs handle them.
>
> I'm not convinced NaN gives us anything useful, especially given how
> badly it breaks sorting. I've been digging into that code a little,
> and it's not going to be pretty. It strikes me as wrong to embed type
> specific info into the generic sorting routines.
>
> So, anyone have any ideas what NaN would be useful for? Especially given
> we have NULL available, which most (non DB) numeric applications don't.
>
> Ross
> --
> Ross J. Reedstrom, Ph.D., <reedstrm@rice.edu>
> NSBRI Research Scientist/Programmer
> Computer and Information Technology Institute
> Rice University, 6100 S. Main St.,  Houston, TX 77005

--
Timothy H. Keitt
National Center for Ecological Analysis and Synthesis
735 State Street, Suite 300, Santa Barbara, CA 93101
Phone: 805-892-2519, FAX: 805-892-2510
http://www.nceas.ucsb.edu/~keitt/