The process of translating a map or spatial data from one geographic projection to another

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3
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161 views

Formula for maximum coverage of a geostationary satellite based on earth station elevation

I am trying to create a javascript function to represent the maximum coverage of a geo satellite for different antenna elevations (0 degrees, 5 and 10 degrees) with 3 leaflet polylines. The result is ...
3
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0answers
722 views

Reprojecting WGS 1984 Web Mercator (EPSG:3857) in Python with GDAL

I am reprojecting rasters in python using GDAL. I need to project several tiffs from geographic WGS 84 coordinates to WGS 1984 Web Mercator (Auxiliary Sphere), in order to use them later in Openlayers ...
3
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537 views

Fortifying re-projected shapefile for ggplot2 in R

I have a shapefile of US county boundaries which I got from the NHGIS. I can load the file using the rgdal package and see information about it: library(rgdal) shp_1860 <- readOGR("shp", ...
3
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66 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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0answers
395 views

How do I pass a LatLng Bounds from Leaflet to Mapfish Print?

I successfully fired up a MapFish print server on Elastic Beanstalk, and it prints out the sample spec files fine, but I'm trying to pass bounds from my Leaflet frontend now, and encountering a lot of ...
3
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0answers
1k views

Converting projected coordinates to google maps pixels

I have a single polygon in a local projection system. I would like to convert that polygon into an image that can be used as an overlay on google maps. I understand that it may be better to use ...
2
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0answers
18 views

Error in Measuring distance using QGIS?

I am using the current Qgis 2.6.1 and having problems using the measuring distance function. The 'Measure Line' is giving me distances which is completely wrong and the scale shown was too big also. ...
2
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62 views

Help with Python/GDAL documentation

The instructions from the url http://gdal.org/gdal_tutorial.html give the following example: dataset = gdal.Open( filename, GA_ReadOnly) with the following description: It's interpretation is ...
2
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72 views

QGIS Problem with extract and warp modules in model builder

I have problems using the gdal modules extract and warp in the model builder. They run correctly when started without the modelbuilder, but when I integrate them in the modelbuilder they won't work. ...
2
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71 views

Clipping and reprojecting in one process for modelbuilder // “Save raster layer as” … in modelbuilder

I want to build a model in the QGIS Modelbuilder. First it should do a clip. Afterwards it should be reprojected (from Geographic WGS84 Coordinates to Gauss-Krüger). I only see one way to do this: ...
2
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81 views

What C/C++ libraries exist to transform vectors between map projections

Has anybody written a C/C++ library (preferably one that is aware of Proj.4 definition strings) that has a set of routines to convert vector quantities (e.g., wind speed and direction) between map ...
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173 views

How to install Proj4js.js in my localhost directory?

I'm developing a GIS website for vineyard management. I am using Openlayers with the WMTS IGN (French institute for geography) datas. It works fine. I also would like to add the possibility for the ...
2
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0answers
62 views

Re-projecting WGS84 to OSGB in SAGAGIS

I took some points with a GPS, and I'm trying to convert from GCS to OSGB 1936 British National Grid in SAGAGIS. I'm working with a shapefile. To reproject the vector layer to the OSGB projection I ...
2
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0answers
192 views

How to generate bounding box based on tile numbers using slippy map tiles method?

Description: I am writing a map cache server for my company. I have to get input data based on tms standard and send a request to wms server to render and cache map files. I am using slippy map tiles ...
2
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849 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 ...
2
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404 views

Geoserver - empty native SRS field

I'm converting layers from shape files to postgis with the below command: shp2pgsql -s 22175 -c -W "latin1" path/file.dbf' table_name db_name | psql -d db_name Next, I add this layer to the ...
2
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144 views

MGRS square identifier to polygon

I'm looking for a function/formula/library that basically takes a MGRS square identifier such as 4QFJ16 and returns me the coordinates of the 4 corners of this polygon in some simple form such as ...
2
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828 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 ...
2
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0answers
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?
2
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520 views

Help converting projection/coordinates to Google Earth

I'm trying to program a GPS style tracker for a simulation game but I'm having a hard time figuring out how to transform the game's coordinates into Google Earth's. The game's world is flat and has ...
2
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0answers
882 views

OSGB36 to WGS84 reprojection 'error'

First off, I am a recent convert to QGIS and am greatly impressed with its ease of use and speed compared with the ESRI products with which I am more familiar - my congratulations and thanks to its ...
2
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494 views

How to overlay geographic data from multiple sources?

Being a newbie to GIS, I am trying to create a map using shapefiles and addresses found online, as an exercise. The steps are below: I downloaded a shapefile of Connecticut from the following link ...
2
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567 views

OpenLayers WMS overlay tile projection

We are using OpenLayers for our GIS Application and we have base files from Ordinance Survey for UK maps. For creating WMS layers, we are generating tiles of 256 x 256 through Sharpmap Library but ...
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20 views

Identify coordinate system used near Kuala Lampur

I have some coordinates that were given to me, and I do not know much about how they were taken. I thought they were UTM coordinates, but when I try to convert them using some online tools I always ...
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21 views

Conversion of (lat, lon, height) from GPS to another CRS

I have latitudes, longitudes and ellipsoidal heights derived from GPS readings, referenced to the ITRF08 system with vertical datum (CGVD2013) - http://webapp.geod.nrcan.gc.ca/geod/hmod/hmod.php How ...
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38 views

Unknown coordinates in Shapefile, projecting doesn't give expected results

I'm reading a Shape file (four files actually, .dbf, .prj, .shp and .shx) containing polygons representing certain areas in my neighborhood. For this I use C# and a library called DotSpatial. I can ...
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77 views

Reprojecting a population raster from LAEA to lonlat

I have a population density raster from the EEA which is based on the CORINE land cover 2000 data. ...
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40 views

How to shift a CRS by an observed offset

I have a drone image is which is geo-referenced over a Google Sat. image. These align well, and both use WGS84-Pseudo Mercator (EPSG:3857). I have a set of data points in a shape file which are ...
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38 views

Reproject xy tiles from mercator to Gauß-Krueger in ubuntu terminal

I´ve exported a map from tilemill as mbtiles and converted them to xyz tiles with help of mbutil. The tiles should be used (for learning purpose) with mod_tile or geoserver and displayed in ...
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0answers
34 views

OpenLayers 2: Transform the geometries for a list of feature objects

I am trying to export GeoJSON for a list of feature objects. The features are in EPSG:3857 projection and I would like to convert all geometries to EPSG:4326. I am perfectly capable of doing this by ...
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95 views

Why does this Geotools Java reprojection to WGS-84/4326 cause offset?

I am using the block of code below. I am reading in a geotif with a UTM zone projection and converting it to 4326. I am pulling out certain multiband values and creating a new raster, when I plot the ...
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80 views

Assign CRS to shapefile in R

I imported my shapefile dat to R with readOGR, coordinates are given in easting and northing, I'd like to change it to latlon and tried: dat_latlon <- spTransform(dat, CRS("+proj=longlat ...
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0answers
142 views

Importing kml google earth polygons to QGIS

I've created some polygons in google earth, saved it to kml and then I loaded these files into QGIS. The problem seems to be the projection, these polygons are slightly out of the place. I've tried ...
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0answers
58 views

Braun/Gall projection and pixel conversion

I am fairly new to projection mathematics and I usually manage to get things to work with copy-paste and trial-and-error but this time I'm lost ... I am trying to map latitude (-90 to 90) and ...
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0answers
54 views

Mapping from one plane on the other plane despite of masking regions

have a set of data given here, where in the first and second columns there are the sky coordinates (ra,dec) e.g. right ascension and declination, respectively and in the third and forth, the ...
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0answers
47 views

Vector seems to be only a pixel of a raster after reprojection

I have the South America hydro1k data for slopes and I am trying to extract the data using point sampling tool with a grid in Brazil's map. My problem is that, even though vector and raster seem to ...
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0answers
86 views

Creating a marker proportionally offset along a line in QGIS 2.4 when re-projecting

One of the nice new features in QGIS 2.4 is to be able to offset markers (e.g. arrow heads) along a line as part of the styling. I am trying to display a dataset of simple lines (not polylines) with ...
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73 views

Why can't I reproject from HARN State Plane Ft Intl to State Plane Ft?

I'm attempting to reproject a feature class that is: NAD_1983_HARN_StatePlane_Oregon_North_FIPS_3601_Feet_Intl to our standard, which is: NAD_1983_StatePlane_Oregon_North_FIPS_3601_Feet When I ...
1
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0answers
64 views

Geodjango transform introduces large errors

Apologies for the possibly naive question. I'm trying to understand how Geodjango (running on PostGIS) deals with coordinate transformations, and am experiencing some unusual behaviour. Let's say I ...
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0answers
150 views

Conversion problem of projection of MODIS LAI from sinusoidal to geographic

I am trying to change MODIS data's (LAI) sinusoidal projection to geographic. Actually I did it. But when I reproject it by ERDAS, the output LAI raster moved about 10 km to west side of actual shape ...
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0answers
77 views

Gauss-Krueger coordinates in Openlayers

I want to show the coordinates of my map in gauss-krüger coordinates, but nothing works. I tried another projection, displayProjection, lonLat.transform but the answers are the same. my source ...
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0answers
129 views

Am I correctly projecting a geometry using a WKID in ArcObjects?

I would like to take in any valid WKID for a spatial reference and then project a single geometry to it. The following code seems to be working, but (1.) can someone verify that this is the correct ...
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0answers
129 views

How to convert MODIS (Vegetation Continuous Fields - MOD44B) to (.img and hdr) in ENVI

Please can anyone help me to convert MODIS (Vegetation Continuous Fields) to (.img and hdr) formats? In ENVI, anytime i try using the MODIS conversion toolkit, a dialog box appears telling me to ...
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0answers
49 views

Create oblique projection?

bit of an odd one which isn't necessarily package-specific. I'm trying to make a tshirt with a map section centred on the plane between San Francisco, USA, to Galway, Ireland. The Great Circle line ...
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0answers
346 views

Reprojecting GeoTIFFs to WGS84/UTM

I'm using libgeotiff and proj4 to read and (try to!) process GeoTIFFs. After reading the file, I want to get the corner coordinates in WGS84/UTM - but there are so many functions and parameters to try ...
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0answers
139 views

Trying to convert to EPSG:27700 (Ordnance Survey) projection, unable to do so

I'm trying to code an interface that allows a user to draw a vector shape on openstreetmap, which is then converted to a WKT string, processed by the server and sent of as a WFS query to emapsite ...
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0answers
72 views

Projection for Tracking a Vehicle

I'm looking for the best coordinate system projection to use for cartesian calculations while a vehicle is running from its starting location to about 100 miles from that spot. The offline format ...
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0answers
282 views

Conversion between WGS84 height and local height datum

For x/y or lat/lon or heights between different ellipsoid, we can do conversion by using proj.4. But I found that if I want to convert between WGS84 height and local height, I found that it is not so ...
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0answers
141 views

Converting altitude in feet to pixels on a mercator map image

I know the question might seem farfetched given that the map is 2d. But I essentially want to project items-aircraft-above the map and I would like their altitude to be vaguely 'realistic' in terms of ...
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0answers
121 views

How to reproject aqua modis images / ocean color?

I am working with aqua modis, ocean color, L2 - SST image but in order to do I must reproject it. I use the gdal_translate to convert the format of the image but reprojection is becoming very ...