Tag Info

New answers tagged

0

The maps were probably hand drawn, then later scanned and may not exactly match the intended projection system. You best bet is probably to georectify the images against known locations and use those georectified images in your application.


3

EPSG:24378 Kalianpur 1975 / India I should be the local CRS in the region you mentioned. The extent seems to fit to that: To get this picture using QGIS, create these text files: E N 73.4775 34.3629 and Easting Northing 3250193.00 1115573.00 3249214.00 1111220.00 Load each into QGIS as Delimited Text File, with blank as delimiter and setting CRS to ...


1

OpenLayers can reproject entire layer, but only at load time (from file or a server). Features added manually (using the addFeatures method) must have their geometries reprojected before adding to a layer.


2

For the Mercator projection, the extent can not reach North and South pole for mathematical reasons. The standard Google and Openstreetmap mercator projection is limited to 85.011° North and South to get a square map. See http://wiki.openstreetmap.org/wiki/Slippy_map_tilenames#X_and_Y for explanation. Using EPSG:3857, the extent of a map is ...


2

I discribed a workflow to get aeqd maps using a sphere instead of an ellipsoid here: Manipulating Azimuthal Equidistant Projections in QGIS If you only want to have 180°, I suggest clipping the resulting picture with a polygon in aeqd projection would be the solution. For a bearing from -45° to 135° from the center of projection at 7E 51N, the clipping ...


0

This issue is now solved in QGIS 2.2, for details see: https://github.com/qgis/QGIS/pull/1081


1

I suggest to change your settings under Settings -> Options, CRS, CRS for new layers to Prompt for CRS You can rightclick on every layer -> Set CRS for Layer and check that your rail data has the custom CRS, but road data another CRS as stated for your library. If the data comes as shapefiles, they should have the correct .prj file with projection ...


2

I think this is a good question and just wanted to add a more explicit answer aimed directly to the original phrasing of the question. No, reprojecting a shapefile does not only change the prj file, it changes both the prj file and the main shapefile contents (the .shp file). The reason being, as demonstrated by @csw, reprojecting a shapefile has to ...


0

Thank you 'mkennedy'. For anyone struggling, the method that worked best for me was to export the data by right-clicking on the layer and choosing data, export data. In that tool, I set it to use the data frame's coordinate system. It produces an Export-Output layer which should be projected correctly.


0

The ortho projection does not cover the whole world, only the visible half. Using the QGIS GUI, your globe would look like this: What you see as nasty artefacts will kill the python script. So you have to clip the world to the vsisble extent. See these Q&A for more advice: Where did the polygons go after projecting a map in QGIS? Ortho Projection ...


0

WGS84 EPSG:4326 does not have metres as units, but degrees. KML files are always in degrees, so you have to set CRS to that, then reproject the layer to someting else with Save As .... Maybe you have used Set CRS for Layer, which is wrong in most cases. The extents you provide are a bit strange. For the kml, yMin and yMAx are very small, even if the point ...


0

CPNO27 is not an official EPSG code, reference ID in QGIS 2.2 is ZANGI:ZANGI:CPNO27. The official one is EPSG:22287 Cape/Lo27 The difference is the axis orientation: CPNO21 has +axis=enu (which is default and can be omitted), while Cape/Lo27 has +axis=wsu. Usually, .prj files do not deal with the EPSG codes, but use the full WKT parameters. QGIS has to ...


0

UPDATE table SET the_geom = ST_Transform(ST_SetSRID(ST_Point(coord_x, coord_y), 2249), 4326)


1

I'm not sure where you found the code epsg:4277 from but it is a representation of the OS national grid in degrees (if I'm reading the EPSG file correctly) the much more common EPSG code is EPSG:27700 which is measured in meters.



Top 50 recent answers are included