Horton

Re: pgsql: Add support for hyperbolic functions, as well as log10().

Dean Rasheed <dean.a.rasheed@gmail.com>

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From: Dean Rasheed <dean.a.rasheed@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Michael Paquier <michael@paquier.xyz>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Lætitia Avrot <laetitia.avrot@gmail.com>
Date: 2019-03-14T08:28:16Z
Lists: pgsql-hackers 
On Thu, 14 Mar 2019 at 04:41, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
> Dean Rasheed <dean.a.rasheed@gmail.com> writes:
> > I'm amazed that jacana's asinh() returned -0 for an input of +0.
>
> Even more amusingly, it returns NaN for acosh('infinity'), cf
> https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=jacana&dt=2019-03-14%2003%3A00%3A34
>
> Presumably that means they calculated "infinity - infinity" at some
> point, but why?
>

Given the -0 result, I don't find that particularly surprising. I
suspect lots of formulae would end up doing that without proper
special-case handling upfront.

It looks like that's the only platform that isn't POSIX compliant
though, so maybe it's not worth worrying about.

Regards,
Dean

Commits

  1. Further adjust the tests for the hyperbolic functions.

  2. Adjust the tests for the hyperbolic functions.

  3. Rethink how to test the hyperbolic functions.

  4. Add support for hyperbolic functions, as well as log10().