[postgis-users] DISTANCE function doesn't work at 179,-179 degrees

[Andrew Edmondson]

I have two points either side of the 180 degree line on a sphere. (example included)
Calling DISTANCE on them, doesn't yield the result 2, but rather 357...
Have I not actually got a sphere?
Or does DISTANCE not do what I expect?

Thanks,

-Ed

<example>

test=# SELECT * FROM location;;
 location_id | latlong          
-------------+--------------------------
           1 |  SRID=4278;POINT(0 0)
           2 |  SRID=4278;POINT(0 90)
           3 |  SRID=4278;POINT(0 179)
           4 |  SRID=4278;POINT(0 -179)
(4 rows)

test=# SELECT DISTANCE(latlong, GeometryFromText('POINT(0 178)',4278)) from location;
     distance     
------------------
              178
               88
                1
              357
(4 rows)

</example>

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Andrew Edmondson
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