[postgis-devel] [PostGIS] #1757: Spheroid length functions returning unexpected results.

[PostGIS]

#1757: Spheroid length functions returning unexpected results.
-----------------------+----------------------------------------------------
 Reporter:  darkpanda  |       Owner:  pramsey      
     Type:  defect     |      Status:  new          
 Priority:  medium     |   Milestone:  PostGIS 2.0.1
Component:  postgis    |     Version:  2.0.x        
 Keywords:             |  
-----------------------+----------------------------------------------------
 This may be related to an older (closed) ticket involving similar sphere
 functions. See #1136 for details on that.

 The geometry and spheroid I'm using for testing are as follows:

 {{{
 POLYGON((-5 -5,-5 5,5 5,5 -5,-5 -5))
 SPHEROID["WGS 84", 6378137, 298.257223563]
 }}}

 The results of the ST_3dlength_spheroid/ST_length_spheroid functions do
 not match with the results from previous versions of PostGIS.

 Here's PostGIS 2.0.0 on my machine:

 {{{
 postgis_2=# SELECT ST_3dlength_spheroid('POLYGON((-5 -5,-5 5,5 5,5 -5,-5
 -5))', 'SPHEROID["WGS 84", 6378137, 298.257223563]');
  st_3dlength_spheroid
 ----------------------
      4429494.47924311
 (1 row)

 postgis_2=# select postgis_full_version();
 postgis_full_version
 ----------------------------------------------------------------------------------------------------------------------------------------------------------
  POSTGIS="2.0.0 r9605" GEOS="3.3.3-CAPI-1.7.4" PROJ="Rel. 4.7.1, 23
 September 2009" GDAL="GDAL 1.9.0, released 2011/12/29" LIBXML="2.7.8"
 TOPOLOGY RASTER
 (1 row)
 }}}

 And PostGIS 1.5.3:

 {{{
 postgis_1_5=# SELECT ST_length3d_spheroid('POLYGON((-5 -5,-5 5,5 5,5 -5,-5
 -5))', 'SPHEROID["WGS 84", 6378137, 298.257223563]');
  st_length3d_spheroid
 ----------------------
                     0
 (1 row)

 postgis_1_5=# select postgis_full_version();
                                          postgis_full_version
 -------------------------------------------------------------------------------------------------------
  POSTGIS="1.5.3" GEOS="3.3.3-CAPI-1.7.4" PROJ="Rel. 4.7.1, 23 September
 2009" LIBXML="2.7.8" USE_STATS
 (1 row)

 }}}

 Here's the PostgreSQL version() information:

 {{{
 PostgreSQL 9.1.3 on x86_64-apple-darwin11.3.0, compiled by i686-apple-
 darwin11-llvm-gcc-4.2 (GCC) 4.2.1 (Based on Apple Inc. build 5658) (LLVM
 build 2336.9.00), 64-bit
 }}}

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/1757>
PostGIS <http://trac.osgeo.org/postgis/>
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