From: Chengpeng Yan <chengpeng_yan@outlook.com>
To: Dean Rasheed <dean.a.rasheed@gmail.com>
CC: Tom Lane <tgl@sss.pgh.pa.us>, PostgreSQL-development
	<pgsql-hackers@postgresql.org>
Subject: Re: [PATCH] Fix overflow and underflow in regr_r2()
Thread-Topic: [PATCH] Fix overflow and underflow in regr_r2()
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Date: Sat, 23 May 2026 02:42:37 +0000
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Hi,

> On May 17, 2026, at 17:16, Dean Rasheed <dean.a.rasheed@gmail.com> wrote:
>=20
> OK, here's a more complete patch along those lines, intended to apply
> on top of the regr_r2() patch.


Thanks for the regr_intercept.patch. The approach looks good to me.

I only noticed a few small things:

1. The patch file seems to have a format issue and doesn't apply
directly. `git apply` reports:

```
error: git apply: bad git-diff - expected /dev/null on line 2
```

2. `dy` seems a bit hard to understand. Perhaps `offset`, as used in the
earlier sketch, would be clearer?

3. Do we need to add tests for the underflow path, and perhaps for the
Inf/NaN guard?

Other than that, this looks good to me.

--
Best regards,
Chengpeng Yan