Horton

Re: [PATCH] Improve geometric types

Tomas Vondra <tomas.vondra@2ndquadrant.com>

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From: Tomas Vondra <tomas.vondra@2ndquadrant.com>
To: emre@hasegeli.com
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Thomas Munro <thomas.munro@enterprisedb.com>, Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2018-08-02T09:50:55Z
Lists: pgsql-hackers 

On 08/01/2018 01:40 PM, Emre Hasegeli wrote:
>> Ah, so there's an assumption that NaNs are handled earlier and never reach
>> this place? That's probably a safe assumption. I haven't thought about that,
>> it simply seemed suspicious that the code mixes direct comparisons and
>> float8_mi() calls.
> 
> The comparison functions handle NaNs.  The arithmetic functions handle
> returning error on underflow, overflow and division by zero.  I
> assumed we want to return error on those in any case, but we don't
> want to handle NaNs at every place.
> 
>> Not sure, I'll leave that up to you. I don't mind doing it in a separate
>> patch (I'd probably prefer that over mixing it into unrelated patch).
> 
> It is attached separately.
> 

OK, thanks.

So, have we reached conclusion about all the bits I mentioned on 7/31? 
The delta and float8/double cast are fixed, and for computeDistance 
(i.e. doing comparisons directly or using float8_lt), the code may seem 
a bit inconsistent, but it is in fact correct as the NaNs are handled 
elsewhere. That seems reasonable, but perhaps a comment pointing that 
out would be nice.

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

Commits

  1. Improve test coverage of geometric types

  2. Fix problems in handling the line data type

  3. Use the built-in float datatypes to implement geometric types

  4. Remove remaining GEODEBUG references from geo_ops.c

  5. Provide separate header file for built-in float types

  6. Refactor geometric functions and operators

  7. Fix crash in close_ps() for NaN input coordinates.

  8. Fix GiST index build for NaN values in geometric types.

  9. Enable building with Visual Studion 2013.

  10. Suppress -0 in the C field of lines computed by line_construct_pts().