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	Wed, 13 Mar 2019 23:18:27 -0400
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
cc: Michael Paquier <michael@paquier.xyz>,
        Postgres hackers <pgsql-hackers@lists.postgresql.org>,
        laetitia.avrot@gmail.com
Subject: Re: pgsql: Add support for hyperbolic functions, as well as log10().
In-reply-to: <fedafa28-e63b-33f3-5d70-12ff94762a9e@2ndQuadrant.com>
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 <20190313022159.GR13812@paquier.xyz> <24813.1552447002@sss.pgh.pa.us>
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Comments: In-reply-to Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
	message dated "Wed, 13 Mar 2019 23:06:51 -0400"
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Andrew Dunstan <andrew.dunstan@2ndquadrant.com> writes:
> Or we could possibly call the function and then turn a result of -0 into 0?

But -0 is the correct output if the input is -0.  So that approach
requires distinguishing -0 from 0, which is annoyingly difficult.

			regards, tom lane