[postgis-tickets] [PostGIS] #2742: Rounding bug using ST_GeomFromGeojson()

[PostGIS]

#2742: Rounding bug using ST_GeomFromGeojson()
---------------------+------------------------------------------------------
 Reporter:  jakeorr  |       Owner:  pramsey
     Type:  task     |      Status:  new    
 Priority:  medium   |   Milestone:         
Component:  postgis  |     Version:  2.1.x  
 Keywords:           |  
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 Let's say I have the following geographical point represented in GeoJSON:

 {{{{"type":"Point","coordinates":[-109.0,35.292506]}}}}

 When I run the following conversion, things work as expected:

 {{{
     SELECT
 ST_AsText(ST_GeomFromGeojson('{"type":"Point","coordinates":[-109.0,35.292506]}'));
        st_astext
     -----------------------
      POINT(-109 35.292506)
     (1 row)
 }}}

 The problem occurs if the string passed to {{{ST_GeomFromGeojson()}}}
 omits the trailing decimal on {{{-109.0}}}:

 {{{
     SELECT
 ST_AsText(ST_GeomFromGeojson('{"type":"Point","coordinates":[-109,35.292506]}'));
        st_astext
     ----------------
      POINT(-109 35)
     (1 row)
 }}}

 Notice how in this case rounding to an Integer value occurs on both
 latitude and longitude. The loss of precision on the latitude value in
 this case is very significant (32.53 km).

 '''Note:''' I left out the CRS field for clarify, the problem occurs
 either way.

 The same problem does not occur using the {{{ST_GeomFromText()}}}
 function. Both numbers are ''not'' rounded to Integers if the first looks
 like an integer.

 Here is my postGIS full version:
 POSTGIS="2.1.0 r11822" GEOS="3.4.2-CAPI-1.8.2 r3921" PROJ="Rel. 4.8.0, 6
 March 2012" GDAL="GDAL 1.10.1, released 2013/08/26" LIBXML="2.9.1"
 LIBJSON="UNKNOWN" RASTER

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/2742>
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