[postgis-tickets] [PostGIS] #3393: ST_Area NaN on some polygons

[PostGIS]

#3393: ST_Area NaN on some polygons
----------------------+---------------------------
  Reporter:  rfc2616  |      Owner:  pramsey
      Type:  defect   |     Status:  new
  Priority:  medium   |  Milestone:  PostGIS 2.2.1
 Component:  postgis  |    Version:  2.2.x
Resolution:           |   Keywords:
----------------------+---------------------------

Comment (by rfc2616):

 We were using the sphere for continuity with old published results. I just
 changed all the queries to use the spheroid and they seem to be running
 fine on 2.2.0 and within a small tolerance of our old sphere-based
 results, so that will get us out of short-term trouble. You're also
 correct that all the sphere based calculations are super crazy right now,
 and not just on the equator.

 {{{
 select analysis_name, analysis_year, region, range_quality, category,
 country, ST_Area(st_intersection::geography,true) spheroid,
 ST_Area(st_intersection::geography,false) sphere from
 survey_range_intersections where analysis_year=2007 order by region,
 country, category;
    analysis_name   | analysis_year |     region      | range_quality |
 category |           country            |      spheroid       |
 sphere
 -------------------+---------------+-----------------+---------------+----------+------------------------------+---------------------+-------------------
  2013_africa_final |          2007 | Central Africa  | Known         | C
 | Cameroon                     |    44861.9693270706 |  3595587.39688914
  2013_africa_final |          2007 | Central Africa  | Known         | C
 | Cameroon                     |    824073902.362827 |               NaN
  2013_africa_final |          2007 | Central Africa  | Known         | C
 | Cameroon                     |    678834776.222033 |               NaN
  2013_africa_final |          2007 | Central Africa  | Known         | D
 | Cameroon                     |    503424735.671734 |  504085360.780887
  2013_africa_final |          2007 | Central Africa  | Known         | D
 | Cameroon                     |    430138925.122056 |               NaN
  2013_africa_final |          2007 | Central Africa  | Known         | D
 | Cameroon                     |    653881544.632783 |               NaN
  2013_africa_final |          2007 | Central Africa  | Possible      | D
 | Cameroon                     |    734248715.634702 |               NaN
  2013_africa_final |          2007 | Central Africa  | Known         | D
 | Cameroon                     |    459.157410163432 |  1815169.69392417
  2013_africa_final |          2007 | Central Africa  | Known         | D
 | Cameroon                     |     80418.939783203 |               NaN
  2013_africa_final |          2007 | Central Africa  | Possible      | E
 | Cameroon                     |    1977273.09717699 |               NaN
  2013_africa_final |          2007 | Central Africa  | Possible      | E
 | Cameroon                     |    1530669683.44256 |               NaN
  2013_africa_final |          2007 | Central Africa  | Known         | E
 | Cameroon                     |    3.43081077933311 |  5.26343760021617
 }}}

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/3393#comment:2>
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