A library for performing conversions between cartographic projections.

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11
votes
2answers
264 views

Huge differences between results for 7-param datum transform

I'm trying to transform a WGS84 lat/lon point 11d42'32.10629" E 5d12'56.75371" S in three different software packages (Proj4, GeoTrans and Leica GeoOffice) but I receive very big differences ...
11
votes
2answers
625 views

How to reproject raster from 0 360 to -180 180 with cutting 180 meridian

I have a geotiff raster image that has a coordinate system with longtitudes from 0 to 360. The horizontal center of the image is 180 longtitude. See image below: I want to transform it to EPSG:4326 ...
8
votes
0answers
446 views

How to define Winkel Tripel in proj 4.8.0?

I have QGIS with proj 4.8.0 installed. I'd like to add Winkel Tripel projection which seems to be defined as +proj=wintri But that definition string does not work. Is this a bug in my proj version, ...
6
votes
1answer
838 views

use proj4 to specify Robinson projection with R ggmap and ggplot2 packages?

I want to project this map in robinson projection: library(ggmap) world <- map_data("world") ggplot() + geom_path(data = world, aes(long, lat, group = group)) ...
6
votes
1answer
650 views

projection/pyproj puzzle, and understanding SRS format

I have a shapefile that has a .prj file, with the following wkt contents: ...
6
votes
1answer
177 views

What is the definition for a geographic coordinate system with east/west bounds of 0 to 360

I need the coordinate system reference or a projection definition that uses geographic (i.e. lat/lon) coordinates but instead of east/west bounds being defined as 180 to -180, I need them to be ...
6
votes
2answers
180 views

Using PROJ.4 library to transform from local coordinate system coordinates to global coordinate system using ground control points?

I have a point cloud whose coordinates are with respect to a local coordinate system. I also have ground control points with GPS values. Can I convert these local coordinates to a global coordinate ...
5
votes
2answers
5k views

Converting X,Y coordinates to lat/long using pyproj and Proj.4 returns the wrong coordinates

I'm writing a python script that reads multiple XML files containing x and y coordinates and combines them all into a single csv file. Latitude and Longitude are required fields in the csv, but I am ...
5
votes
4answers
1k views

PostGis ST_Transform: failed to load NAD27-83 correction file (-38)

So I'm getting some user drawn polygons in WKT with OpenLayers. (Web Mercator CRS) and I now need to now convert it to SRID4326 so can do some spatial queries. However, when it fails to do a ...
5
votes
2answers
2k views

what is the best way to programmatically convert between WKT and Proj4 string?

some shapefiles have a .prj file associated with it. and the .prj file contains the projection info of the shapefile in the format of WKT. Sometimes I need to convert WKT to proj4 string, and ...
5
votes
2answers
320 views

Stereographic projection of WGS84 ellipsoid on a plane[python]

I would like to ask you for help in following task. What I need to do is to derive local x,y coordinates from latitude, longitude, applying stereographic projection of WGS84 ellipsoid on a plane, ...
5
votes
1answer
256 views

pyproj, proj4 doesn't return same coordinates after inverse conversion

I'm trying to interpolate between coordinates, as a step in that process I convert latlong to UTM so I can work in metric. I don't get the expected latlong when converting back, reproduced below: ...
5
votes
1answer
544 views

Does anyone know the proj4 Coordinte Reference System command line for Rectangular Polyconic Gores?

I am a GIS beginner using QGIS 1.8.0 I am trying to transform a world map from the standard WGS84 Coordinate Projection System to a set of rectangular polyconic gores, with a gore count of 12. ...
5
votes
1answer
128 views

Having trouble finding out what coordinate system a map is using, and how to convert it

I'm using Small Area shapefiles in Ireland from the Central Statistics Office (CSO) website. The link to these is here http://census.cso.ie/censusasp/saps/boundaries/ED_SA%20Disclaimer1.htm (Look for ...
4
votes
1answer
572 views

How do I solve a “No PROJ.4 translation” error with gdal?

I've installed gdal using the brew utility on OS X so the proj and geos dependencies were also installed. I'm now trying to warp a GeoTIFF so that I can import it into Google Earth. I am getting a ...
4
votes
1answer
633 views

Openlayers/Proj4js not transforming coordinates the first time

Something seems to be going wrong with my transformations. Before I added proj4js, transforming a coordinate went fine: new OpenLayers.LonLat(-1.0, 52.0).transform(new ...
4
votes
1answer
123 views

Problem with custom projection definition in Qgis

I want to define a custom crs valid for Mexico. The context is that older cartography in Mexico is based on the NAD27 datum. I wanted to test the following proj4 string +proj=longlat +ellps=clrk66 ...
4
votes
1answer
410 views

How to define a CRS using a projection rotated about a given point

I have a data set that uses a common projection, but has its own false easting and northing, and is rotated 315 degrees. I need to be able to work in this CRS and easily translate from one CRS to ...
4
votes
1answer
387 views

How to make PROJ4 on windows including NZ datum shift grids

Can anyone point me to an example of how to 'make' proj4 including the New Zealand datum shift grids? I understand I need to include the shift grids in the build, just not sure how to make it on ...
4
votes
1answer
2k views

Converting Lambert Conformal Conic to WGS84 using Proj.4

I am attempting to transform data from Lambert Conformal Conic lat/long and I am having some issues with the results. The shapefile I am attemtping to transform can be found here: ...
4
votes
1answer
117 views

GDALWARP and OGR2OGR / CS2CS not agreeing on transformation

I am trying to transform some data (both raster and vector) from WGS84 to a Croatian Coordinate system defined by: +proj=tmerc +lat_0=0 +lon_0=15 +k=0.9999 +x_0=5500000 +y_0=0 +ellps=bessel ...
4
votes
2answers
175 views

SRS: geographic or cartesian?

Let's have a list of SRS with proj4 definitions (e.g. spatial_ref_sys table). Is there a way to determine whether given SRS is geographic (lon,lat) or cartesian (x,y)?
3
votes
1answer
238 views

Are these two OGC WKT projections the same? And if so, why are their reference strings different?

So here is the .prj text of a federal shapefile dataset of all public airports in its native OGC WKT format: ...
3
votes
2answers
134 views

Convert file with coordinates, keep record ID

I have the following sample data: 345 -515561.05 -1166540.03 456 -515542.01 -1166548.76 999 -515519.61 -1166552.19 789 -515505.29 -1166550.25 321 -515477.05 -1166546.82 201 -515431.12 -1166534.06 197 ...
3
votes
2answers
787 views

Leaflet proj4leaflet with multiple projections

I am looking at having both EPSG4326 tiles and EPSG3857(cloudmade) tiles on a single map (but separate layers). I have been looking at the proj4leaflet plugin, and it "appears" to me that this might ...
3
votes
1answer
81 views

Location for floorplan

Is there an application / service where I can put my floorplan of a building en 'position' it on the right place on the earth? (The buildings location). I found TileMill an application where I can ...
3
votes
1answer
553 views

how to add a custom SRID to Spatialite

I'd like to create a spatialite database and load it with shapefiles using the Mississippi Transverse Mercator (MSTM) projection, but it doesn't have an EPSG definition in the spatialite library of ...
3
votes
3answers
1k views

How to define ITRF 92 and ITRF 2008 using Proj4 parameters in QGIS?

I know how to define a CRS, but this particular one is giving me a headache. I was unable to find the EPSG code at spatial reference. The main reason for asking this is that raster and vector data ...
3
votes
1answer
871 views

Proj4js objects not readyToUse

I am using Proj4js to transform between WGS84 and a local Swedish grid RT90 (EPSG:2400). It works in FF, but in IE the Proj objects often is not readyToUse when I need them to. I use this code to ...
3
votes
2answers
2k views

How to integrate Proj4 into an iOS / iPhone project?

This may be overkill, but I need to reproject a point coming from the CLLocationManager, which is in EPSG:4326, to Dutch RD (Double Stereographic, EPSG:28992) in my iOS application and I am using ...
3
votes
1answer
314 views

Get the geotransform in Mercator given a pixel size away from the origin

I have a radar image with the following information: The projection is Mercator (Mercator_1SP in GDAL) The projection origin is 0º lat 0º lon At a given geographic coordinates (e.g. lon=10º ...
3
votes
1answer
151 views

proj4 cookbook?

Is there a proj4 "cookbook"? I discovered proj4 from @MerseyViking excellent answer to: Create Mercator map with arbitrary center/orientation? but most of the documentation appears to be fairly high ...
3
votes
1answer
298 views

What's wrong with my Proj4 transformation?

I am having trouble converting a projected coordinate EPSG:28355 to WGS84 EPSG:4326 using Proj4js. I know by default Proj4 will not convert to EPSG:28355 so I went to spatialreference.org and got the ...
3
votes
0answers
233 views

How to set GDAL/cs2cs/proj to use NTv2 grid shift file when using EPSG codes?

I am using the GDAL API for Python for a script that takes only EPSG codes for inputs to specify source and target coordinate systems. While the cs2cs command seems to handle quite well ...
3
votes
0answers
60 views

How can I specify a spatial reference system which has a north pole different than the standard north pole?

I have a geographic spatial reference system (i.e., latitude and longitude) which has a north pole that is not the usual north pole: it's the magnetic north pole at approximately 70.30 degrees north, ...
2
votes
4answers
2k views

OpenLayers transform EPSG 27700 coordinate to Google 900913

Community, I'm currelty capturing my mouse click event and trying to transform the coordinates into Long Lat. I need to get at the Long Lat as strings so I can build a url and throw it at Google ...
2
votes
3answers
129 views

Can someone recognize the CRS?

I'm using QGIS 1.8.0 and have some shapefiles with a "User Defined CRS" which I don't recognize. Is anyone able to recognize it? Here is an image of the settings I see on QGIS. Thanks in advance. ...
2
votes
3answers
156 views

How to find and apply reprojection parameters?

I have a data set in one projection, and a shapefile in another, and I am trying to combine the two. I am using Python. I apologize for posting a "help me transform coordinates" question on this site ...
2
votes
1answer
730 views

Projection ETRS89 (Ellipsoid: GRS80) 6-Degree Zone 33 to UTM33N - WGS84

Hi I'm having trouble to reproject a shape file in Qgis. The projection is supposed to be "ETRS89 (Ellipsoid: GRS80) 6-Degree Zone 33" and I would like to project it to UTM33N - WGS84 (EPSG 32633). ...
2
votes
3answers
4k views

How do I include proj4js in openlayers?

in my Openlayers app, since the base map projection is not epsg900913 or 4326, I need to include proj4js in order to use geolocation feature. but i got such a error notice: GET ...
2
votes
1answer
71 views

Shapefiles from Nationalgrid without a .prj file - what projection are they in?

Im working with these shapefiles: http://www2.nationalgrid.com/uk/services/land-and-development/planning-authority/shape-files/ They show pipelines & electricity grid of the UK. They do not ...
2
votes
1answer
27 views

WGS84 CRS without elipsoid

What's the difference between using CRS defined as +proj=longlat +datum=WGS84 +no_defs and a CRS defined as +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs Will using one or the other pse any ...
2
votes
2answers
497 views

Why is Spatialite delivering “Invalid SRID” error message

Qspatialite in QGIS 1.8 (and also Spatialite-gui) delivers an "Invalid SRID" error message when I try to load shapefiles with a SRID value of 3814 (Mississippi Transverse Mercatur). The SRID is ...
2
votes
1answer
976 views

How to setup leaflet map to display a WMS layer in ESRI:102012 projection?

I have a WMS server that serves layers in ESRI:102012 projection. http://spatialreference.org/ref/esri/102012/ It accepts GetMap requests with srs=EPSG:102012 parameter. My goal is to display a map ...
2
votes
3answers
211 views

How would you use change the projection within KML file?

I have created some KML files by converting the projection with both ARC and MapWindow. I'm looking for ways to automate exporting the data from our application with coordinates in State Plane ...
2
votes
2answers
1k views

How to perform transformations using ProjNet?

While writing some unit tests I thought it would be convenient/possible to use ProjNet to convert from EPSG:4326 into several other coordinate systems (3875,3395). I figured it would be as easy as ...
2
votes
1answer
478 views

compiling a c++ program using proj.4

I am real new to C++ and am having trouble compiling a C++ program that uses the proj.4 library. I downloaded and compiled and installed the proj.4 library on my machine. So, the '/usr/local/lib' ...
2
votes
1answer
608 views

What is wrong with this Proj4 transformation?

I'm implementing support for WMS maps in my company's software. Servers return a list of projections their maps are available in, but our software only displays data in WGS84 (lat/lon or UTM), and ...
2
votes
1answer
74 views

Choosing correct proj4string in R for a set of points

I was given a set of points which I eventually will overlay with a polygon shapefile in R. The issue is that the person who provided me with the points did not give them to in long/lat coordinates but ...
2
votes
1answer
75 views

How to do a raster reprojection in QGIS with custom map parameter

I'd need to reproject a raster dataset in a new customized projection, but I'm fairly new at both QGIS and GDAL and I'm not exactly sure about how to proceed and what the exact syntax is. The ...