A library for performing conversions between cartographic projections.

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GDAL/proj4 equirectangular projection coordinate system units assumed by OGRSpatialReference and GDALDataset::GetGeoTransform()?

How do I configure my OGRSpatialReference object to specify an equirectangular projection system http://en.wikipedia.org/wiki/Equirectangular_projection where the affine geo-transform matrix (provided ...
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1answer
81 views

Most efficient way to use UTM in leaflet

Our server is using UTM internally. We then send a large number of UTM Coordinates to display them in a custom made leaflet layer. First we transform (unproject) them into "normal" geographical ...
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1answer
418 views

OpenLayers and custom Proj4 Projection

ok so I'm a newbee in using OpenLayers. I try to map some planetary data on my webMap server using OpenLayers. I defined a proj4 projection as follow: Proj4js.defs["MYDATUM"] = "+proj=longlat ...
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1answer
66 views

Is it possible to get all projections form OGR?

I'm working on a project where the user can give my program so GIS data which may or may not have which projection it is using. So is it possible to get a list of all the projections from OGR or ...
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1answer
265 views

How to transform/convert Coordinate Reference System with Proj4 and php

Basically my question is: Can I combine the functions of proj4 with php in my server? For example, I would like to know if it is possible get data in WGS84 and transform in ETRS89. I need to get ...
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682 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, ...
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445 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 ...
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63 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, ...
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212 views

PyProj/Proj4 convert geographic to projected coordinates for Geostationary Data

I am trying to convert geographic coordinates (in degrees east/north lon lat) to projected coordinates in meters for geostationary full disc data (GVAR Goes East data from CLASS). To do this, I tried ...
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663 views

How do I solve Gdalwarp error 'too many points failed to transform' for remapping Geostationary to Lambert conformal?

I am trying to remap from Geostationary to Lambert conformal using gdalwarp. My input data is in netcdf, and is in geographic coordinates (degrees) and I would like to output the remapped data to ...
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138 views

Proj4 inconsistent longitude after projection

All coordinates expressed in this question are (longitude, latitude), the default for proj4. London is at (-0.1460838, 51.5170986), and San Francisco is at (-122.419302, 37.775549). According to the ...
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786 views

Projecting point in Leaflet from EPSG 900913 (same as 3857) to EPSG 2232 with proj4js returning unexpected results

I have a leaflet map from which I want to be able to query an api that accepts x y values in EPSG 2232 as inputs. Leaflet doesn't handle point transformations like Open Layers does so I am trying to ...
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99 views

Proj4s.js Library Transformation Accuracy Documentation

I am using proj4s.js for transforming between coordinate systems for a GIS web application. Is there any documentation out there on transformations accuracy provided by the library?
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112 views

How do I use Proj4Leaflet projections correctly?

I'm loading data layers from a WMS server into a Leaflet map, and I need to give the user a choice of projections. For the WMS server requests, I just need to change the CRS parameter to a different ...
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0answers
81 views

Can't project ArcGIS Tiled Service for Esri-Leaflet

I'm following this example from the esri-leaflet docs. I have an ArcGIS Tiled MapService in ESRI:102696. So I'm trying to use Proj4Leaflet to project the service and use it in my application. I ...
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114 views

Creating custom projections with Proj4

I'm reading into how to customise projections with Proj4 - specifically to achieve tilted projections such as the example below (from vis4.net) The Proj4 literature is pretty heavy going and having ...
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122 views

Problem with custom projection in OpenLayers

I'm using OpenLayers 2 with Proj4JS 1.10. When trying to change the map's projection using Proj4js.defs['STEREOGRAPHIC:180,90'] = "+proj=stere +lat_0=90 +lon_0=180 +a=3396190.0 +b=3396190.0 +over=F ...
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0answers
57 views

How can I obtain the unit of a projection SRID?

Given a projection SRID, is there a way I can obtain the coordinates unit string (meter, degree, ...) ? In PostGIS for example, it looks like it is present in the srtext column of spatial_ref_sys. ...
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0answers
161 views

proj/pyproj converted coordinates offset

I'm using pyproj to convert some coordinates from WGS84 to OSGB36. When mapped out the converted and unconverted don't map to the same places on a map. The OSGB36 coordinates are mapped about 100 ...
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0answers
217 views

How can I fix badly specified geographic coordinate system with units in arc-seconds?

Check out this depth-to-rock soil data. It is linked from here. The spatial reference system is a latlon, but the units are arcseconds. I could not reason out how to override the SRS even after ...
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167 views

proj4's omerc projection (cs2cs) broken?

When I project longitude -60, latitude 0 to mercator, I get the expected answer: > echo "-60 0" | cs2cs +proj=lonlat +to +proj=merc -6679169.45 0.00 0.00 However, when I project it to ...
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On the usage of Proj4Js->tmerc.js

I am using "proj4js & open layers" for my mapping. I got projection & datum (which is based on "Transverse Mercator") of a local plane and this plane is part of a grid which returns ...
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349 views

Conversion From Transverse Mercator To Longitude & Lattitude

I have to transform (7-parameters datum transformation) coordinates from northings & eastings to lattitude & longitude. Following are details of source coordinate system(i.e. northings & ...
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331 views

How do I use Proj4js or other technique to make custom map projections with google.maps.Projection?

I'm using Google's Projection class to try to convert my map projection from the default spherical mercator to something like Lambert Conformal Conic. I was previously adapting the code from this ...
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153 views

Proj4js can't handle 90/180degree transformations from 4326

So if you try to do a transform like this Proj4js.transform( new Proj4js.Proj( 'EPSG:4326' ), new Proj4js.Proj( 'EPSG:3857' ), new Proj4js.Point( -180, -90 ) ...
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proj.4 definition for (obsolete) UK War Office “Italy South” grid

I'm helping a friend convert his late father's war diary coordinates to WGS84. I have a proj.4 definition that appears to work in QGIS, but if I transform a scanned map with gdalwarp, it's not even ...
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223 views

Leaflet + proj4js + EPSG:2180

I'm trying to add a WMS layer in EPSG:2180. I get the definition for EPSG:2180 from here and I am using this guide on GitHub to make a new CRS definition, but I think it is corrupted. It is not ...
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93 views

How can I create Albers projection of Russia map?

I need a conic tranformation of map, so this code var map = L.map('map', { crs: new L.CRS.proj4js('EPSG:4326', '+proj=aea +lat_1=52 +lat_2=64 +lat_0=0 +lon_0=105 +x_0=18500000 +y_0=0 +ellps=krass ...
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136 views

Map doesn't show anything in img file (WMS-Mapserver)

Actually in a practical Project we wanted to use OpenLayer and MapServer to display our data using WMS, but We can't find a proper srs or EPSG code. One of the ITC students said, we have to change our ...
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222 views

What parameters are useful for an Albers equal area projection map of the world

I have a data set which contains global points. I would like to convert from long/lat to Albers equal area. However, the http://spatialreference.org proj4 world parameter values are actually for the ...
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103 views

How do I determine programmatically what values to add to the proj4js constructor for a CRS or SRS such that I can iteratively render proper overlays

I think this is primarily a GIS based question as far as for example: var crs = L.CRS.proj4js('EPSG:2154', '+proj=lcc +lat_1=49 +lat_2=44 +lat_0=46.5 +lon_0=3 +x_0=700000 ...