A map projection is any method of representing the surface of a sphere or other three-dimensional body on a plane

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Openlayers GeoJSON write not maintaining projections

How do I get GeoJSON.write to maintain the projections used in the construction of the GeoJSON? points.geojson {   "type": "FeatureCollection",   "features": [     {       "type": "Feature",       ...
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34 views

How to calculate areas for data that covers the whole of Australia [duplicate]

I have a polygon shapefile showing mining areas across all of Australia. I want to calculate the area for each of the polygons however they have been provided in a Geographic Coordinate System ...
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2answers
60 views

What data projection should I use for area analyses in different countries at a global scale

I'm creating A4 maps to show where forest cover and mining fields overlap across the globe. Each A4 map focuses on a specific country (e.g. India, USA, China, Australia...). For each country, I need ...
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50 views

QGIS Server & custom CRS

I'm using QGIS Server and an OpenLayers-based web client (in EPSG:3857). I have a QGIS project that I want to serve with QGIS Server, containing layers in several CRS, including custom ones. ...
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18 views

Geoserver import does not recognize projection

Using GeoServer 2.8 and the Data importer plugin I can import shapefiles generated in ArcMap with WGS84 geographic coordinates (EPSG:4326) and UTM+WGS84 projection (epsg:32724). As a reminder, ArcMAP ...
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1answer
68 views

How do I fix distortions when reprojecting cshapes world maps?

I am using the cshapes package in R as a source of historically accurate country borders. While the default WGS 84 maps plot fine, I would like to reproject the maps. This introduces some distortions ...
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85 views

How to test polar stereographic projection for a specific longitude intersection?

I'm writing a library that tests grids defined by map projections for intersections, and am running into an issue implementing the test for polar stereographic and rectangular projections - ...
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1answer
35 views

Reprojecting Tifs [duplicate]

When I import some geotifs into QGIS, they use a reference of 0, 360. My basemaps are all -180, 180. Both the basemaps and geotifs use the same CRS, WGS84. So the geotifs display starting at 0 on the ...
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2answers
357 views

Add scaleline control to openlayers 3 map with unknown projection

I've a mapguide map display with openlayers 3 like this: var options = { "minZoom": 0, "maxZoom": 100, "center": [mapInfos.center.x, mapInfos.center.y], "extent": [mapInfos.extent.minX, ...
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1answer
155 views

Why do pyproj and matplotlib basemap produce different results when they convert my lat-long data into a CRS?

pyproj and matplotlib basemap seem to produce differing x-y values when they convert my lat-long data into the same CRS (such as Albers Equal Area). These x-y values tend to be off by hundreds of ...
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31 views

Is it safe to query for points contained within polygons using a lat-long projection?

I'm querying for points contained within a polygon. All data - both points and polygons - is stored in latitudes and longitudes. Technically I should probably project this data to a suitable local ...
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21 views

Should I set the projection if the data has already been projected?

I need to plot some data which was produced on a native grid with a lambert conformal conic projection. I need to create a geotiff (using python and gdal) and was wondering how to go about and do ...
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19 views

change projection for openlayers map with kml file

I use the basic example shown in dev.openlayers.org/examples/sundials.html to display kml files areas, with map.zoomToExtent(kmllayer.getDataExtent()) to auto center and zoom. The problem is that ...
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125 views

how to set the geotransform using GDAL in python

I am trying to create an image from a numpy array and georefenrece it so that I can import it into qgis. I have the latitude and longitude in degrees for the top left corner of the array as well as ...
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51 views

problem with area calculation in QGIS

I encountered a problem in QGIS 2.10.1 when I tried to calculate the areas of polygons in a polygon layer. I followed the instructions here ...
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0answers
36 views

How to create raster with origin in degrees and dx dy in metres

I need to create a raster from array. In gdal if i understand correctly i need to specify the top left lat lon for the SetGeoTransform((originX, pixelWidth, 0, originY, 0, pixelHeight)) however the ...
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28 views

Projected Coordinate System issue using GDAL and qgis when defining x and y

I have a numpy array which I would like to save as GeoTiff using GDAL in python. The array was created using the following PCS in mind: +proj=lcc +lat_1=48 +lat_2=48 +lat_0=48 +lon_0=0 +x_0=0 ...
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1answer
31 views

Get pixel geo info according projection and map extent

I would like to know if it is possible to calculate the geographic coordinates (lat, lon) for a pixel specified by its x/y (top-left) cartesian coordinates in a map image/raster? The datum and ...
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1answer
128 views

On the fly reprojection in QGIS?

I'm new to QGIS and trying to deal with on the fly reprojection. I have three layers : a shapefile in EPSG:4326 a raster in EPSG:3395 that same raster reprojected in EPSG:3857 (with QGIS via the ...
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1answer
27 views

Ways to make distances more apparent

I have made this map: The intention of the map is to make it clear that the distances is shorter from Luleå than from Rome. As you can see that is not the case here. Which ways are there to make ...
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2answers
73 views

Coordinates transformation

I have the following data base with information about rainfall for a set of meteorological stations: year station latitude longitude depto municipio date rainfall 1990 11010010 0527 N ...
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2answers
169 views

How to convert projected coordinates to geographic coordinates without ArcGIS? [closed]

I'm trying to convert a series of points from Easting Northing to LatLong, I have this working perfectly in Arc but ideally I would like the algorithm to do it through our own system. It is a huge ...
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1answer
39 views

$area calculation doesn't work or wrong projection?

I've been reading the QGIS manual and I've encounter a problem I don't know what to do. I downloaded data from OpenStreetMap and the raster from http://srtm.csi.cgiar.org/SELECTION/inputCoord.asp The ...
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1answer
64 views

Issue rendering polygons at global scale when using the Robinson coordinate reference system in QGIS 2.10

I am trying to create a map using the Robinson coordinate reference system (EPSG:54030) in QGIS 2.10, on Mac. I used the 'on the fly projection' feature in the Project Properties. My base layer is a ...
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17 views

Google Earth Mapping in Beijing - Why is it shifted? [duplicate]

When using Google Earth Pro, the road network and the underlying imagery do not line up. At first I thought this was a road network issue. However, when I geolocate addresses using the Baidu ...
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1answer
218 views

Zoom Scale in OpenLayers 3

Need to change the default zoom of OpenLayers 3 to do so adapted scales, type [1: 100000, 1: 50000.1: 25000.1: 10000.1: 1000.1: 500] have seen in Openlayers2 if you can, but at 3 I have not found a ...
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1answer
71 views

What projection should I georeference this historical map to?

I'm using ArcGIS. I have a historical map from 1884. It has bathymetry information which I would like to compare to modern bathymetry models with as much accuracy as possible. I don't know what ...
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1answer
83 views

GeoServer WMS correct WFS wrong coordinates for line features?

I'm calling my geoserver with WMS and later WFS to retrieve vector data (both times EPSG 4342. All features are correctly rendered in WMS and QGIS, so I'm sure the original data is fine. The original ...
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1answer
130 views

Adding OpenLayers basemap to a QGIS project changes the CRS to WGS 84 / Pseudo Mercator

I have a QGIS (2.10.1) project that contains several shapefiles, all of which are EPSG:3338 (NAD83 / Alaska Albers). The project property CRS is also EPSG:3338. All of the shapefiles display ...
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36 views

Geographic Center of Earth centric Projections [duplicate]

This is more a question born out of curiosity than actual needs, but this seems like the right place for it. Based on What is Centroid of all lands of Earth? I was wondering what world maps centered ...
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28 views

How can I change the projection used by the QGIS Browser preview?

QGIS Browser has no settings in the UI. Is there any file or so where I can define this?
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1answer
83 views

Disparity between QGIS and ArcGIS for Desktop georeference results?

I am georeferencing a static map in JPEG format. I would prefer to use QGIS for a variety of reasons. I've never georeferenced with QGIS before, so I may not have the process quite right. I ...
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1answer
121 views

layers don't match on OpenLayers

So in my Openlayers 3.9.0 I use Bing Maps and OSM layers, they both are EPSG 3857 var layer = new ol.layer.Tile({ source: new ol.source.OSM({}) }); var bingMapsAerial = new ...
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0answers
21 views

Geographic projection for ASCAT metop-a product

I have an ascat bufr over souther south America and I need to project raster data over a map. What is the right projection for this product? I'm lost with this options: ortho, mercator and ...
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36 views

Loading AHN files correctly into MicroDEM?

In the netherlands we have the ahn elevation data files(to be found on: http://geodata.nationaalgeoregister.nl/ahn2/atom/ahn2_05m_ruw.xml) (based on rd projection). If i imort these files into ...
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2answers
58 views

Convert NAD_1983_Georgia_Statewide_Lambert to NAD83

All I have a ESRI generated shapefile that uses: NAD_1983_Georgia_Statewide_Lambert Here is the projection information: ...
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1answer
42 views

What projection is this?

Can anyone figure out this projection? Eckert III looks close but is not quite right.
3
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2answers
126 views

Which SRIDs to use for what tasks?

I try to understand the idea behind the different Spatial Reference Identifiers. I understand that the different SRIDs identify different projection views on the earth and that they are important for ...
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2answers
197 views

Coordinate/projection system issue in ArcGis 10.3

I am new in this community and I am also a new user of ArcMap. I am facing a problem, my shapefiles are in a GCS WGS 1984 and I have to add a new shape file that is in a projected coordinate system ...
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35 views

Sinusoidal Projection and ArcInfo Sphere Datum Woes

I am using published forest loss data (found here: http://glad.geog.umd.edu/indonesia/data2014/index.html) that uses the ArcInfo Sphere datum with a sinusoidal projection. I am seeking to transform a ...
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1answer
81 views

Bringing multiple non-projected CAD .dwg files over to ArcMap as a projected ESRI .shp

Is there a streamlined method to bring over CAD .dwg files that have unknown coordinate systems into ArcMap as ESRI .shp files and project the coordinate system of each new .shp accordingly? I have ...
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1answer
32 views

Why does not equal computing line in `OpenLayers` with `ArcGIS` when i use measure control?

My map projection is: "EPSG:900913" ,Display projection is "EPSG:4326" and units is "m", however does not equal the length is calculated in OpenLayers with ArcGIS, in fact Openlayers show the length ...
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1answer
81 views

Understanding precision of ArcGIS geodatabases?

I would like to know how precision is handled in ArcGIS software. Is it using a real Computer Algebra System engine, an arbitrary precision library or do others tricks to handle precision ?
2
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1answer
116 views

How to make slope map from elevation map in Lat/Long?

I have an elevation raster map of the world, in Lat/Long. When I make a slope map, the results of the raster cells will be either 0, or values close to 90. The problem seems to be that the Slope ...
2
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1answer
99 views

Natural Earth doesn't render well in Robinson World projection

QGIS Pisa 2.10.1 Mac Pro, Mac OS I don't seem to be able to create a simple World Map using the Natural Earth Dataset and the Robinson World projection, unless I zoom in. What could be the problem? ...
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1answer
110 views

Use lamber 93 imageOverlay with leaflet on top of OSM tiles layer

I'm trying to use a lambert 93 image overlay on top of an Open Street Map title layer. var map = L.map('map'); L.tileLayer('http://{s}.tile.osm.org/{z}/{x}/{y}.png', { }).addTo(map); var coords = { ...
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53 views

Data not showing in QGIS when connecting to Oracle

I have an Oracle XE 11g spatial database that is connected to a web map. All the layers of the web map are stored in the database and they work just fine. I sometime need to edit some of the layers in ...
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0answers
56 views

Does Leaflet handle TopoJson in OSGB EPSG:27700 projection?

I already have a Leaflet map showing custom base map tiles in British OSGB projection, EPSG:27700 (using the Proj4Leaflet plugin). I would like to overlay some nationwide admin boundary data in the ...
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42 views

Old MIller projections Bipolar Oblique Conic Conformal/Oblated Stereographic definitions?

I'm attempting to georeference and warp some old toposheets that are various old projections including the following: Miller Oblated Stereographic Projection Bipolar Oblique Conic Conformal What's ...
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3answers
231 views

How to create a Projection from a CRS string using pyproj?

I'm trying to convert between two coordinate systems using pyproj: import pyproj p1 = pyproj.Proj("+init=EPSG:4326") p2 = pyproj.Proj("""PROJCS["NAD27 / California zone ...