1
vote
1answer
32 views

Can't get SRS from PostGIS using Proj4 text

I'm having a problem transforming a point from the Australian MGA UTM datum (eg MGA Zone 51 http://spatialreference.org/ref/epsg/28351/) to WGS84 using GeoDjango. I've narrowed that down to a problem ...
0
votes
2answers
61 views

Coordinate System Google Maps API

I am making an application in java using GMaps4JSF where the person will enter the address on the map I'll take this coordinate and consult on my postgis base regions in which region this point is ...
1
vote
1answer
110 views

Help defining custom CRS in QGIS 2.2

I'm trying to use EPSG:4479 in QGIS. 1) If I search for EPSG:4479, it returns a "Imported from GDAL" EPSG:4479, but it does not work. At the console, the following message is displayed: ERROR 6: ...
1
vote
1answer
56 views

Trouble using ogr2ogr w/ -s_srs to combine inconsistent EPSG files into my postgis DB

I'm having trouble combining shapefiles from TIGER and different local governments into a single postgis db to query legislative locations. I've imported all data to multipolygon geom, but found some ...
1
vote
1answer
72 views

QGIS with CH1903/LV03 and WGS84 layers

I have a few CH1903/LV03 layers (lake, river and the country border of Switzerland) and a layer in WGS84 (two points of two cities, Vaduz and Bregenz). On-the-fly-transformation is activated but ...
1
vote
3answers
107 views

How ensure data put into PostGIS gets proper CRS attached?

I recently had an intractable problem that we finally traced back to the fact that some points in a PostGIS table had a CRS associated with them and others did not. This resulted in some points being ...
2
votes
2answers
399 views

finding the correct transformation (from EPSG:31300 to EPSG:4326) or how to store two srid in one table

I have a very specific problem. I have data crossing two coordinate-systems, more specifically: the Netherlands and Belgium. Previously the data was stored in one table in Oracle, using the RD ...
3
votes
1answer
545 views

Setting coordinate system in PostGIS

The geographical information data that INEGI (part of the Mexico's goverment) provides are in the following coordinate system (or is projection?) Lambert Conformal Conic, double standard parallel ...
3
votes
1answer
278 views

Mapping latlng values to a point on a HRAP grid

I have a copy of some NWS rainfall data loaded into a PostGIS database. Given a lat lng point, I want to find the rainfall for that given day. The original data are in XMRG format and projected ...
1
vote
1answer
107 views

Geometry has incorrect latitude-longitudes

SELECT ST_SRID(geom) AS s FROM zones GROUP BY s; returns a single record: 4326 SELECT Find_SRID('public', 'zones', 'geom'); returns 4326 SELECT AsText(geom) FROM zones returns geometry like: ...
0
votes
2answers
168 views

How can I find the SRID from the WKT out of a GRIB file?

I have a grib2 file which I'm trying to import into PostGIS 2.0 Raster and process. Trouble is, I can't figure out what the SRID is supposed to be, or one close enough for government work. Running ...
2
votes
1answer
167 views

Calculating points in the USDA's Cropland Data Layer coordinate system

I need to integrate against the USDA's cropland data layer. They've got a demo and some API docs. The important query I need to run is this, given an (x, y) of say (1551459.363, 1909201.537): ...
9
votes
2answers
1k views

Which function for creating a POINT in PostGIS?

When defining a Point in PostGIS, when do you decide to use which of the following? ST_SetSRID(ST_MakePoint(lon,lat),4326) ST_SetSRID(ST_Point(long,lat),4326) ST_SetSRID(ST_GeomFromText('POINT(lon ...
0
votes
1answer
158 views

Openlayers Linestring over edge of map

im trying to create a route displayer for ships. But im struggling with the edges of the map. When going from ie. 179* to 2* it displays a line across the entire map, instead of displaying it on the ...
2
votes
2answers
1k views

What Spatial Reference System do I store Google Map's Lat/Lng in

I am new to PostGIS, Spatial Reference Systems and projections and want to store lat/lng coordinates retrieved from Google Maps and Openstreetmap and its services like the Geocoder/Nominatim. I'm ...
3
votes
1answer
121 views

How to bulk import ESRI projections into Postgis

Where can I get a file that would allow me to bulk upload all of the ESRI projections into the spatial_ref_sys table of postgis. I know that you can get insert statements on spatialreference.org; ...
1
vote
1answer
923 views

Convert latitude longitude coordinate to x y coordinate?

I'm using a postgis database and java to develop my application. I need to transform my geographic data currently in latitude/longitude format into a x/y format. I found solutions based on UTM ...
1
vote
1answer
1k views

SRID 4326 and geometry conversion

From this line: SELECT ST_AsEWKT(geom) FROM buildings LIMIT 1; I get this result: "SRID=4326;MULTIPOLYGON(((404269.308014269 4543087.6184561,...)))" I'm wondering if the coordinations are ...
0
votes
1answer
128 views

Why does Find_SRID return zero?

using SELECT Find_SRID('public', 'myTable', 'myColumn'); I get zero as the result, what does it mean? Regards,
4
votes
1answer
245 views

extracting pixel value from a table in postgresql

I have a table in postgresql that contains ID, row number, column number, pixel value and centroid of the pixel in WGS84 lat-lon system(4326). How could I extract the pixel value by giving a point in ...
2
votes
0answers
363 views

PostGIS: ST_Transform function conversion problem

I'm inserting map data from a GML file with srid EPSG:27700 into a PostGIS database table with srid EPSG:4326. I'm using the ST_Transform function as in this snippet: ...
2
votes
2answers
285 views

Ordnance Survey osgb:BNG spatial reference system not recognized by PostGIS

I'm trying to load an Ordnance Survey GML file into PostGIS using the ST_GeomFromGML function. The problem is that the spatial reference system that is used in the file, osgb:BNG, is not recognized by ...
9
votes
2answers
1k views

How can I convert geomagnetic coordinates to geographic coordinates without doing the math myself?

I have some data which are in geomagnetic coordinates; that is, they are latitude and longitude, but in reference to the magnetic north pole in Canada rather than the geographic north pole. As you ...
5
votes
2answers
2k views

What is the SRID of census.gov shapfiles?

I downloaded the county files from: http://www.census.gov/cgi-bin/geo/shapefiles2011/main I cannot figure out what SRID to use with them. When I am trying to generate a class file from ./manage.py ...
1
vote
1answer
98 views

Which SRS is computational more effective to store continental scale data? (given some conditions)

For a Precision Agriculture application I need to make calculations in UTM projection. The data will be stored in Postgis and is made of soil samples results (point data) and field boundaries of many ...
3
votes
1answer
2k views

How to get the coordinate system from a PostGIS database?

My question is probably amazinlgy stupid, but I can't find the answer myself. I would like to extract from a database the latitude and longitude of points. For now, I'm getting x(the_geom) and ...
6
votes
4answers
458 views

Where should I start advanced GIS learning

I am relatively familiar with most of the GIS stuff. I develop GIS applications as well with open source offerings. Still I find some lapses in my theoretical knowledge in GIS. What resources can you ...
17
votes
5answers
3k views

How do you best deal with data that spreads across UTM Zones?

I have data that spreads across two UTM Zones GDA/MGA94 UTM Zone 55 and 56. I have layers such as a cadastre, roads, pipelines etc where I want to store measurements like lengths and areas in metres ...