The process of converting the coordinates of a map or an image from one system to another, typically by shifting, rotating, scaling, skewing, or projecting them.

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2
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1answer
147 views

Setting coordinate systems in QGIS: “transform error caught”

I'm learning how to use QGIS (v 1.8.0 "Lisboa") on Mac OS 10.6.8. My goal is to create a simple county map of Illinois using the base data shapefiles available from the Illinois Natural Resources ...
6
votes
1answer
290 views

locating latitude-longitude point in a piste-map with matrix transforms

I am trying to plot points of a particular latitude longitude on this image of a Swiss mountainous landscape. What I am doing is I have some 54 known location-points plotted on this image (not ...
1
vote
1answer
169 views

How to reproject this vector layer?

I have a dxf file and use this tool to convert it to shapefile. Then I apply some affine transformations and get a shapefile that does not fit the shapefiles downloaded from osm (EPSG:4326). I know ...
2
votes
1answer
562 views

ArcObjects 10.1 .NET Convert Point from WGS1984 to OSGB1936

Please can someone help me convert a point in WGS1984 to OSGB1936, I have followed all the documentation (or so i think...) and yet have not made any headway into this problem. This is my code : Type ...
4
votes
2answers
433 views

What's the best projection for rasterization of random latitude and longitude data in the northern Atlantic?

I have a dataset in the WGS84 geographic coordinate system that I would like to interpolate along a grid using Python. It appears gdal_grid is not available through the Python bindings, so I plan to ...
1
vote
1answer
68 views

How does ogr2ogr determine which transformation to use and how big would the introduced error be?

I want to convert TIGER data GEOGCS["GCS_North_American_1983", DATUM["North_American_Datum_1983", SPHEROID["GRS_1980",6378137,298.257222101]], PRIMEM["Greenwich",0], ...
1
vote
0answers
177 views

How to use CropCoverage Render Transformation in Geoserver SLD (WPS)? [closed]

I have yet to find an example on the web (or in code) of anyone using the "Crop Coverage" Render Transformation from a Geoserver SLD. Does anyone have an example or at least be able to point me to ...
2
votes
0answers
688 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 ...
1
vote
0answers
381 views

ArcPy 10.1 PointGeometry.projectAs()

I'm trying to reproject an X,Y passed in from an Add-in. So far this works fine: pointGeometry = arcpy.PointGeometry(arcpy.Point(x,y),srIn,False, False) projectedPoint = ...
3
votes
1answer
654 views

getting the specified geographic transformation, or at least the GCS, of a data frame

First, the TLDR digest: I'm getting a bogus value from dataFrame.geographicTransformations on some machines; how do I get the correct value as shown in the properties dialog? and/or Given a spatial ...
2
votes
1answer
903 views

Openlayers Transform not transforming a point from EPSG 27700 to EPSG 4326

I am trying to add Google street view functionality to a Openlayers Map. I have started by using 3 divs to hold the Openlayers Map (which uses a local tilecached base map), a google api map and ...
2
votes
1answer
61 views

OSGB conversion error

So I am using ArcGIS 10 and trying to work in British National Grid. My shape file is in WGS84 UTM30N. By chance I passed the shape file across to a colleague and we both transformed into BNG. When ...
2
votes
0answers
123 views

What's the difference between CRS 4326, CRS 4978, and CRS 4979?

CRS 4326, 4978, and 4979 are all based on WGS84. 4326 is called "geographic 2D" 4978 is called "geocentric" 4979 is called "geographic 3D" What are the differences between these three? And why ...
9
votes
1answer
702 views

How can I see the coordinate transformation parameters in QGIS?

How can I see (and edit if possible) the transformation method and parameters used by QGIS for "on-the-fly" transformation, and then for saving data in another CRS? Like in ArcGIS? Here is the ...
0
votes
1answer
175 views

Terrasolid - How to define spherical mercator (EPSG: 3857)

Im trying to define the srs EPSG 3857 inside Terrasolid sofware. I ran into a problem because the definition of the reference ellipsoid is given with a major axis and inverse flatening, not via both ...
1
vote
1answer
101 views

Problem transforming projection on outlying features from shapefile [closed]

I am fairly new to GIS data and as such please feel free to ask for extra data I might not have provided. I have some regional data from Natural Earth, more specifically this: ...
3
votes
2answers
421 views

How to transform coordinates to location in x-y grid in R?

I have a polygon with a 40m diameter and several points that lay inside it. Now I want to reformat the point locations (projected in DHDN/GK-3, but could vary) to x-y coordinates ranging from zero to ...
2
votes
2answers
447 views

How to create a “Datum-less” projection in QGIS?

I want to use QGIS to do some georeferencing and image registration. On ArcMap10 I can define an "Unknown Projection", basically a default metric grid, and use it as a grid for georeferncing. In QGIS ...
2
votes
0answers
153 views

projection discrepancy with gdal (1.9) and proj4

I boiled the problem down to that python example: import sys try: from osgeo import gdal from osgeo import osr except: import gdal import osr if __name__ == '__main__': version_num = ...
2
votes
2answers
158 views

Coordinate system of a raster file to be introduced for transformation

I am working on raster data using GDAL. When I extract coordinate system information of the files I got this: PROJCS["Geostationary_Satellite", GEOGCS["GCS_Unknown datum based upon the custom ...
3
votes
1answer
532 views

Coordinate system of a MODIS file to be introduced in GDAL for transformation

I am working on MODIS data using GDAL. When I extract coordinate system information of the files I got this: Coordinate System is: PROJCS["unnamed", GEOGCS["Unknown datum based upon the custom ...
8
votes
1answer
2k views

How to reproject a raster file in QGIS with datum transformation?

I want to reproject a tiff raster file from projection A (ETRS89/UTM Zone 32) to projection B (DHDN/Gauss-Kruger zone 2). The two projections have a different datum so I have to use a datum ...
2
votes
2answers
1k views

Howto change OpenLayers BBOX request projection?

My map uses EPSG:900913 projection on the map. All coördinates in the database are stored in the 'normal' google format / GPS coordinates (WGS84). For instance, if you save a new location..Before I ...
2
votes
1answer
1k 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 ...
0
votes
2answers
157 views

How to apply v.transform on a set of vector layers (GRASS 6.4)?

I have 64 vector layers, all of them must be warped using the v.transform module; the pointsfile is the same for all vectors. How can I apply the transformation recursively to all layers? I'm not ...
2
votes
3answers
358 views

Datum transformations, do we use wgs84 as an intermediate common reference?

I was transforming some data the other day using the 7 param helmert transformation and it got me thinking. I have a set of transformation parameters, but these only describe the transformation from ...
2
votes
2answers
465 views

Looking for formula for the Robinson projection

I'm looking for a source that describes how the Robinson projection is calculated. I'm going to use this for converting long/lat into Robinson coordinates in both R and in javascript.
6
votes
1answer
951 views

Python script to convert Lat Long to ITM (Irish Transverse Mercator)

I am currently working on a python script that converts Lat Long (WGS84) to ITM. The formulas used are based on a paper published by OSGB (Appendix B): ...
2
votes
0answers
178 views

How to decode Magellan URL coordinates to lat/lon

Magellan uses this URL to designate a coordinate in New York: mgn:///address/?coord=merwFvlqbM,name=Viva%20Herbals%20Pizzeria,number=179,street=2nd%20Avenue,city=New%20York,country=US How can I ...
8
votes
1answer
1k views

Computational most efficient way to convert Cartesian to Geodetic Coordinates

As far as I understand the literature there are several ways to convert a set of geoecentric cartesian coordinates to geodetic coordinates Bowring, 1976 Borkowski, 1989 Lin & Wang, 1995 Toms, ...
2
votes
2answers
435 views

How to transform Lambert coordinates in C#?

I want to transform Lambert (EPSG:3035) coordinates to EPSG:4326 in C#. I have tried this: var lambert = cf.CreateFromWkt("PROJCS[\"ETRS89 / ETRS-LAEA\",GEOGCS[\"ETRS89 ...
3
votes
1answer
2k views

How to use OpenLayer.Transform?

I want to draw a rectangle. The coordinates are somewhere in northern Germany. But the rectangle shows up in the Near East? What am I doing wrong? var epsg900913 = new ...
0
votes
1answer
193 views

coordinate projection

I'v got a detail map for an event as PDF an made an openlayers slippy map with Maptiler. I now need to place markers at the position of gps/gsm-trackers, which store their coordinate on a server. The ...
3
votes
1answer
505 views

Transform multiple layers as one unit in ArcGIS 10?

The general/conceptual question: Is there a way to transform multiple layers together in ArcMap 10 (on Windows XP SP3) as one unit? More specifically: I have an ArcMap document with a georeferenced ...
1
vote
1answer
433 views

Reprojecting non 4326 WMS image to spherical mercator

In OpenLayers, I'm trying to display a WMS overlay (EPSG:4269) from a server I don't have control over to a spherical mercator projection. Is there an equivalent to this: ...
3
votes
2answers
517 views

Error transforming EPSG:4326 to EPSG:90013

When I'm trying to run a map on geomajas an error has occurred: o.g.internal.service.GeoServiceImpl - Problem during transformation EPSG:4326->EPSG:900913 of MULTIPOLYGON The multipolygon ...
3
votes
1answer
530 views

PostGIS 2.0 ST_Transform with Rasters cannot find custom SRID

I'm trying to calculate an average value in a buffer around a point. Given a raster in EPSG 4326 and a similar point, this is fine, except that the values will be skewed as they are not projected in ...
1
vote
1answer
401 views

How to transform ETRS to EPSG?

I have data in the ETRS 89 LAEA format (SRID: 3035). But I have problems to transform it. Example data: N2736 E4541 I want to transform it to EPSG WGS84 (SRID: 4326), to check the coordinates on ...
3
votes
1answer
305 views

How does latitude of origin work in Mercator

I'm trying to make a coordinate transformation using GDAL/osr python bindings. I have a longitude an a latitude and I want to transform them into the mercator coordinates. So I define the mercator ...
1
vote
0answers
173 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
votes
2answers
171 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 ...
0
votes
1answer
123 views

How to adjust/convert/transform set of points with unknown crs using reference points

I have a set of points in an unknown crs. How can I convert (not guess) this to a given crs? I know, or rather I can determine the actual coordinates of each point in order to have some reference ...
2
votes
0answers
508 views

Use MS SQL Server to convert MGRS to Lat Long

Below is the SQL for converting Military Grid Reference System (MGRS) to decimal Latitude and Longitude. It is very accurate, but not perfect. If you can make it work 100%, it is yours, but PLEASE ...
4
votes
1answer
388 views

EPSG operations and operation methods

Querying through the EPSG database, I can see the tables epsg_coordoperation where transforms and conversions between different CRS are stored, and epsg_coordoperationmethod which stores the ...
3
votes
1answer
121 views

How can i get a transformation-parameters-report (spatial-adjustment)

everyone! In ArcGIS resource center about spatial adjustment (How Transform works), there are transform report like this ! Scale (X,Y) = (249.927,249.927) Rotation (degrees) = (0.362) Translation = ...
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 ...
5
votes
2answers
521 views

Translating all features in a shape file

I have a friend with a bit of a problem. He has 1000+ shape files mapping paddocks and being used for precision agriculture. He's recently discovered the base station positions used to create these ...
0
votes
2answers
600 views

Setting spatial reference for MapInfo tab-file

How can I change spatial reference for tab-file in MapInfo Professional?
5
votes
2answers
4k views

Rotating a vector layer in QGIS with qgsAffine (or other method)?

I would like to rotate a set of vector points in QGIS an arbitrary number of degrees around a central point (or arbitrary point). This is similar to a recent question about creating a regular grid; ...
1
vote
1answer
2k views

Adding EPSG:3857 / 900913 to Oracle's mdsys.cs_srs

I am working with an Oracle Standard database at version 11.2.0.1.0. I also have access to XE version 11.2.0.2.0. The later version has both SRIDs 900913 (Google Mercator) and 3857 (official Web ...