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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Trouble Correctly Projecting from ETRS to UTM

Task is to project a DEM from ETRS_1989_UTM_Zone_30N to WGS 84 / UTM zone 29N. Easy enough right? Process succeeds, but inaccurately. I have recently read on this ESRI Geonet post that ArcDesktop ...
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NED (NAVD88) to WGS84 heights

I need to convert the 1/3 arc second DEM files from the NED into WGS84 ellipsoid heights. The documentation says that the NED is referenced to NAVD88. I've tried using gdalwarp as follows: gdalwarp ...
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Map Projections - WHAT?

I have a problem (C#.NET): What I have: Points with a coordinate (Lan & Lon) A canvas (WPF) with a dynamic size A control which represents a point A zoom factor, the kilometres from right to ...
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Raster Layer doesn't display, TileMill

I'm attempting to add a raster layer to TileMill, but for some reason the raster doesn't seem to be reading in correctly. I used gdalwarp to reproject the raster file to EPSG:3857 and then import it, ...
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How is EPSG:4326 data 'projected' in a 2D map?

I like to think I'm relatively well-versed in datums, projections, and coordinate reference systems, so if this is a stupid question I will suffer eternal shame. OpenStreetMap data is stored in WGS84 ...
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1answer
25 views

Plot a world heat map with mollweide projection in R

I have a data set with global observations with lat/lon information. There are 288 longitudes from -179.375 to 179.375 with spacing 1.25, 180 latitudes from -89.5 to 89.5 with spacing 1. There is one ...
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1answer
640 views

OpenLayers and custom Proj4 Projection

I am trying to map some planetary data on my webMap server using OpenLayers. I defined a proj4 projection as follow: Proj4js.defs["MYDATUM"] = "+proj=longlat +a=1740000 +b=1740000 +units=m +no_defs"; ...
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1answer
29 views

Restore previous versions of Qgis file

I´m trying to recover a previous version of a Qgis file, because I started playing around with CRS, and saved the file and closed it, thinking next time it woud be easy to get everything back into ...
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How can I find EPSG when it's not obvious from the .PRJ file?

Using Geoserver, I'm trying to get the correct projection for a map layer that is provided by the State of Idaho. I've tried looking up the EPSG code from http://prj2epsg.org/search. However, the ...
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Two layers of the same region with the same coordinate system does not lay in the same place! [duplicate]

I know that my problem seems to be frequent but I couldn't find any good till answer. I have two layers for the same place (area and roads) in my ArcGIS, both of them has the same coordinate system ...
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1answer
620 views

Georeferencing LAS files in geographic coordinates (lat/lon) or in cartesian (projected) ones?

First of all, I am a newbie in GIS. I have a lidar point cloud with GPS and telemetry data associated. Then, I transform coordinates of every point to an ECEF coordinate system and finally I ...
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677 views

Getting the projection of a LAS file using liblas?

I am using the python api of liblas to read/write las files. I would like to get the spatial reference information of the las file using liblas, but have been unable to figure it out. Can anyone ...
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1answer
388 views

Get Radius in epsg 4326 with Openlayers 3

What is the best method for getting the radius of a circle in Openlayers 3 in epsg 4326 (geodesic)? I'm using this example for a base and trying to draw a circle while getting the radius, but using ...
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26 views

R Levelplot overlaying two SpatialPolygonsDataFrame on a RasterLayer

I'm having some trouble plotting a RasterLayer and a SpatialPolygonsDataFrame in a level plot in R. Something is wrong with the projection, but I don't manage to understand what. Here you can find my ...
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Importance of CRS in Getis-Ord Gi* hotspot analysis

I have a question about the importance of the chosen CRS in a Getis-Ord Gi* hotspot analysis - I am running a hotspot analysis (using Zone of Indifference spatial relationship) on a quite restricted ...
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22 views

Which SQL Server spatial data type to use for UK data in SQL Server?

Which spatial data type should be used for UK data in SQL Server?, i.e. GEOMETRY or GEOGRAPHY? I'm aware of OS National Grid and my understanding is it's an X/Y coordinate system, covering from ...
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57 views

Problem aligning historic map of Poland [closed]

I have downloaded a historic map of Poland. I am having a problem aligning it to a modern map. I have tried various methods and coordinate system using over 50 points, but nothing works. It gets ...
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1answer
141 views

What is my coordinate system preserving?

I'm trying to get a better grasp of coordinate systems, datums, projections etc. I understand that certain systems preserve different things; distance, shape, angles, area. I'm wondering how you can ...
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1answer
83 views

Put points on a projected world map

With the help from this post Lines on reprojected sp objects with Mollweide projection, I draw a world map using Mollweide projection. I also have some points with latitudes and longitudes, and I ...
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1answer
390 views

ScaleLine shows NaN for LCC projection

I have used openlayers along with geoserver. My Map is having LCC projection by default, but SRS is EPSG:4042. The problem is that the scaleline shows NaN in meter as well as feet. How can I correct ...
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1answer
31 views

Assigning CRS using las2las from libLAS?

My las file had a spatial reference of "None." I tried to assign the CRS (in which data were collected) with the following command line: las2las flightline_002.las --a_srs EPSG:32632 lasinfo ...
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1answer
261 views

Combining UTM zones into one solid map

I have an area, example 4000m x 4000m. So, 4x4km. The origin can be placed anywhere, maybe in center, maybe on the top-left, nevermind. Now, I want to fill this area with some stuff from OSM. I read ...
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1answer
939 views

Finding projection of point to line?

I have a segment defined by 2 LatLon points(A and B) and a third LatLon point (C). I need an alghorithm, formulae, or some code to find the projection point of C on the segment AB (call this point D) ...
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1answer
31 views

Getting Borders as SVG using Peters Projection

Is there now, in 2016, a place where I can easily download the borders of all countries and continents as SVG using Peters Projection? Or what is the easiest way to get those? (I haven't installed ...
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2answers
1k views

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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21 views

ArcGIS project raster mosaic bends the raster but not the footprint when projecting

I have mosaic whose rasters are using a custom coordinate system: US_IFR Authority: Custom Projection: Lambert_Conformal_Conic false_easting: 0.0 false_northing: 0.0 central_meridian: -95.0 ...
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12 views

Reprojecting and Aggregating a 30m resolution raster to a 3 arcsec raster

I am a using a 30m x 30m resolution land use raster that is projected in NAD83 Québec Lambert but would like to convert it to make it compatible with a 3 arcsecond flow accumulation raster that is ...
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2answers
751 views

OpenLayers WMS - TypeError: this.resolutions is undefined

I'm trying to setup a map with WMS and WFS Layers by using Geoserver. However, when I'm combining WFS and WMS (with some Google basemaps) together in one map I got following error in Firebug: ...
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41 views

Getting Error 000151 from ArcGIS Projection?

I'm having big problems with arctoolbox of ArcMap 10.3.1 to project almost all my layers from TM65 - Irish Grid to IRENET95 - Irish Tranverse Mercator.I always get the error 000151 and the Help is ...
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1answer
34 views

Area calculations using a layer in a projected data frame versus a projected feature class in ArcGIS

So I've been tasked with automating a formerly manual process in model builder in which I'm trying to calculate land area. In the former manual process the feature class was brought into ArcMap and ...
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31 views

Gdalwarp UTM reprojection causes image distortions

I'm trying to re-project Sentinel-2 images to a common UTM zone in order to create a mosaic. For this I'm using gdalwarp with the following syntax: C:/OSGeo4W64/OSGeo4W.bat; gdalwarp -t_srs ...
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1answer
44 views

Produce Oblique Mercator Map

To avoid the possibility of opinions, let me rephrase the question. Which software packages are able to produce an Oblique Mercator map between any two arbitrary points, similar to what is offered in ...
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2answers
79 views

Reproject raster without projection info

I'm pretty new to gdal and got a presumably easy question for experienced gdal users. My problem: I have a raster ascii file of which I don't know the projection or epsg code. However, I want this ...
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1answer
194 views

How to get projection data (.prj) of raster image using GDAL/OGR?

I start with a boundary shape-file (think U.S. states) in lat/long that I convert to some projection, and then rasterize the result as a .tif. What I need now are the raster coordinates of the ...
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1answer
22 views

Web Mercator to 3d globe projection problems

I've been trying to use map tile images from services like OpenStreetMap to create a globe, and I've mostly succeeded. The problem is that when I compare my globe to one using the same image source ...
2
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1answer
38 views

Problems with matching vector data with raster data

I’m new in Arcgis, and I have some trouble in this task: I downloaded from ICC (www.icc.cat) a raster data map that is a in a specific coordinate system, if I right click to view its properties, it ...
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2answers
206 views

Defining coordinate reference system with rotation in GeoServer?

I am using GeoServer and have a layer in EPSG:900913 ("Google Mercator"). I need to "rotate" the map around certain point (say, 1500000, 7000000) by certain degree (say, 30 degrees clockwise). How ...
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2answers
40 views

D3 can't render GeoJson file (Simple structure in Montreal, Canada) created in QGIS

I am attempting to render SVG and attach it to a div with id="map". I can do this successfully with GeoJson which I acquired from this tutorial: http://maptimeboston.github.io/d3-maptime/#/1 Excerpt: ...
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2answers
82 views

What kind of projection is this?

Can someone tell me what the projection is in this zone map from NOAA? I am trying to replicate it (or get close) in QGIS.
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1answer
19 views

Discrepancy between shape area and data from municipality [closed]

I am attempting to map several parcels just to show very basic dimensions (frontage, etc.) and parcel area. I have the parcel area from the municipal assessor's office in acres. And I have a parcel ...
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1answer
31 views

Can gdalwarp reproject from ESPG:4326 (WGS84) to UTM?

I've a GeoTIFF image in ESPG:4326 (WGS84) and when I try with gdalwarp to reproject to UTM, it has problem gdalwarp -s_srs "EPSG:4326" -t_srs '+proj=utm +zone=33 +datum=WGS84 +units=m +no_defs' -of ...
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0answers
45 views

Warning, inconsistent extent!

I have a raster that was provided to me from another institution that plans to provide this data (and many more layers) from a thredds server for download to the public. Correct me if I'm wrong; my ...
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2answers
57 views

OpenLayers 3 / Cesium polygon projection issue

I am using OpenLayers 3 and Cesium (via ol3-cesium). I have created a few rectangles (using a MultiPolygon) stacked on top of each other. Whereas in OpenLayers the rendering (left) is as expected, ...
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2answers
98 views

Is it possible to restore lost PRJ-Files?

Currently I am working on a project with QGIS (2.14.1). Therefore I need to add old (but important) shapes that were drawn by a colleague. Somehow most of the .prj-files are missing - I don't know ...
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2answers
88 views

Openlayers 3 connecting to a wms feed with a different projection

I am trying to incorporate a wms feed in the British national grid projection (EPSG:27700) into a openlayers 3 project. I initially had used this wms layer in an openlayers 2 application using the ...
2
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34 views

Creating Proj4 string for local coordinates

I am fairly new to coordinate system conversion, so am rather lost on the following problem. We have been using Proj4 to convert between various coordinate systems which is fine for known coordinate ...
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1answer
52 views

Check if point is within radius of another point with Shapely

I've successfully used Shapely with python to check if a point is within one of a set of polygons in a .shp file but now would like to check if a point is within a circle of radius x miles from ...
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1answer
22 views

R: Krovak projection in R - identical in ArcGIS, different in R?

I have two files: shapefile and raster, both in the same coordinate system in ArcGIS: EPSG 5514. Check information on projection in ArcGIS for raster: S-JTSK_Krovak_East_North WKID: 5514 Authority: ...
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2answers
264 views

Mapping Russia - Int'l dateline splitting polygon

I am having the issue where the International Dateline is splitting a polygon I am working with. I have a layer of the "Federal Districts" of Russia, and the eastern most federal district is being ...