A library for performing conversions between cartographic projections.

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1k views

Mapping x, y pixel coordinates to latitude and longitudes on the WGS84 datum

Apologies in advance for the long question, I am fairly confused at this point and I figure if I show my thought process any flaws early on in the piece can be more easily pointed out. I have a grid ...
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3answers
2k views

How to convert Lat/Long to UTM using Proj(4j) similar to JScience UTM.latLongToUTM?

I'd like to use Proj(4j) to convert between UTM and Lat/Long coordinates. I used to use JScience for UTM <-> LatLong conversions like this: UTM.latLongToUtm(latlong, ReferenceEllipsoid.WGS84); ...
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3answers
233 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 ...
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0answers
164 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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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, ...
3
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1answer
160 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 ...
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3answers
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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 ...
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2answers
349 views

Geodjango - using projected coordinates with olwidget

I have a database in GeoDjango containing data based on the Australian MGA54 coordinate system (SRID 28354). I have the srid set in the model definintions and when using the standard GeoModelAdmin ...
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1answer
175 views

Looking for CRS for NAD 83 UTM Zone 30N

I'm curious as to why the UTM zones are incomplete for NAD 83 in QGIS? I have a WGS84 shapefile that I would like to project to NAD83 UTM Zone 30N but can't find it in the QGIS CRS list. I see how ...
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Conversion from N,E to Lat/Long And Lat/Long to N,E will always be same? [closed]

I have an excel tool for the conversion of following lat/long: Lat: 23° 11’ 24.67503’’ S Long: 118° 46’ 6.15742’’ E , which gives me following N,E: Northing: 7,434,317.43 Easting: 680,991.69 But I ...
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181 views

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 ...
0
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2answers
179 views

How do you pass parameters for Proj4js implementation with OpenLayers

I am using Proj4js along with OpenLayers for the transformation of x,y (projection type is Transverse Mercator) to long, lat. While executing "inverse()" method what I noticed that in tmerc.js some ...
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1answer
134 views

Tool For Generating Formula for Projection

I am using Proj4Js for northing,easting to lat,long transformation. My Datum is "AGD84" and projection is "Transverse Mercator". While doing so I found that if I don't specify "+proj" parameter in ...
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1answer
1k views

Generating Map Tiles for MGRS Grid Graticule

I'm possibly a bit out of my league here, but ready to get my hands dirty. I want to generate map tiles for a MGRS grid graticule similar to http://tiles.mapbox.com/mapbox/map/afghanistan-mgrs. I ...
2
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1answer
264 views

Proj4 Task not working - Northing Easting to Lat Lng

I usually post in StackOverFlow - if this is the incorrect area to post - I apologise. I have trying to convert a lot of northings / eastings to lat lng I have code below working: In ruby using ...
2
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1answer
840 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). ...
3
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1answer
371 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 ...
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335 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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1answer
100 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 ...
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313 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 ...
4
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1answer
496 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 ...
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2answers
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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 ...
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607 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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1answer
373 views

Can we use proj to offset coordinates?

Can someone please help me construct a proj string to offset coordinates? The detail we have - one coordinate point in a local construction grid, and the corresponding WGS1984 LatLong which we ...
4
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1answer
497 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 ...
2
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1answer
570 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' ...
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4answers
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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
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1answer
689 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 ...
6
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1answer
757 views

projection/pyproj puzzle, and understanding SRS format

I have a shapefile that has a .prj file, with the following wkt contents: ...
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152 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 ) ...
6
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1answer
191 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 ...
5
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4answers
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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 ...
3
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3answers
5k 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 ...
3
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1answer
964 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 ...
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1answer
456 views

How to resize layer using .prj (WKT) projection? (Geographic Coordinate System)

Briefly: How to parametrize .prj WKT file so that I can perform 7 point tranformation (wiki). I know how false_easting and false_northing params work, but how can I adjust scale? I do not mean ...
6
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3answers
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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
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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 ...
3
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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 ...
4
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1answer
3k 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: ...