Horton

Re: [PATCH] Improve geometric types

Alvaro Herrera <alvherre@2ndquadrant.com>

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From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, emre@hasegeli.com, Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>, Thomas Munro <thomas.munro@enterprisedb.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2018-09-27T20:59:17Z
Lists: pgsql-hackers 
On 2018-Sep-27, Tomas Vondra wrote:

> I may be missing what you're saying, but point_mul_point is not just a
> simple multiplication of coordinates, i.e.
> 
>     (x1,y1) * (x2,y2) != (x1*x2, y1*y2)
> 
> It essentially does this:
> 
>     ((x1 * x2 - y1 * y2), (x1 * y2 + x2 * y1))
> 
> so I wouldn't be surprised if this was a difference between _pl and _mi.

Yeah, I had misinterpreted the operation before reading the code, then
when reading it I realized the formula is what you were saying, so I
updated the final part of my reply but failed to realize I had written
my misunderstanding in the first portion.

-- 
Álvaro Herrera                https://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().