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I am using Django 1.3, PostGIS 2.0 , Postgresql 9.0 and GeoDjango.

I had a database with a table for places. This table had latitude and longitude for places in the US. I enabled this database with PostGIS. I added PointField to my model. Then, updated this table with

SELECT AddGeometryColumn('table', 'poly', 4326, 'POINT', 2)

CREATE INDEX "table_poly_id" ON "table" USING GIST ( "poly" )

UPDATE table
SET poly = ST_PointFromText('POINT(' || longitude ||' '|| latitude ||')', 4326)

Now, I want to make query to find places within 5 miles of given latitude and longitude of a user's location. So, I did this

ref_pnt = fromstr("POINT(%s %s)" % ("-87.627778", "41.881944"))
records = Table.objects.filter(poly__distance_lte = (ref_pnt,D(mi=5)))

But, I am getting an error

DatabaseError: Coordinate values are out of range [-180 -90, 180 90] for GEOGRAHY type

I also get an error when I do this

SELECT ST_PointFromText(poly) FROM table 

ERROR:  parse error - invalid geometry
HINT:  "0101000020E61000007E" <-- parse error at position 20 within geometry
CONTEXT:  SQL function "st_pointfromtext" statement 1

What could be the problem?

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2 Answers 2

I had a similar problem, in my case, I was storing coordinates inverted.

In WGS84 and postgis, the order in point is longitude, latitude.

In Django, the point object is like: Point(x=longitude, y=latitude)

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i think the problem is about projection system. my advice is that connect your postgis table to qgis. and then open your table and reproject it to WGS84.

EDIT:

SELECT placename, st_astext(geom), st_x(geom) AS x, st_y(geom) AS y
FROM Points           
WHERE
        st_x(geom) < -180 OR
        st_x(geom) > 180 OR
        st_y(geom) < -90 OR
        st_y(geom) > 90;

this sql code checks if your geom objects greater than 180 and 90...

i hope it helps you...

share|improve this answer
    
How to solve the projection system problem? I opened the table in qgis and set to WGS84. But how to reproject? –  carlsen Apr 26 '12 at 8:45
    
for qgis reprojectioning. after this save your file and then use SPIT tool - Shapefile to PostGIS Import Tool, overwrite your old file... –  Aragon Apr 26 '12 at 10:17

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