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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projection from epsg:4326 to epsg:4258

I'm looking for projection functions to convert coordinates in 4326 to coordinates in 4258 and viceversa. Any suggestions?
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2answers
74 views

What is wrong with my projection

I am using OpenLayers to plot a point on a map; the point should be located in the UK; but keeps appearing in the middle of the ocean (0,0). I have check my projection and I think this is correct. ...
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2answers
48 views

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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1answer
26 views

Los Angeles county aerial imagery

I am looking for a basemap of LA county showing aerial imagery similar to google earth. However, I also need it in a specific projection: NAD_1983_StatePlane_California_V_FIPS_0405_Feet. Does anyone ...
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11answers
4k views

Discontinuous or Interrupted map projections?

Do any of the current open source GIS softwares support discontinous projection systems? E.g. sinusoidal, dymaxion, butterfly, etc? If not, are there any affordable commercial ones that do (affordable ...
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0answers
41 views

Aligning layers in QGIS?

I am new at QGIS and am having a problem aligning layers. Possibly I just don't understand how projection works. I have 2 layers: 1) GPS waypoints collected in a GPS UTM zone 55N 2) polygon ...
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0answers
15 views

Requesting Mongodb collection with 2dsphere index from Leaflet LatLng

I am using projection and 2dsphere index. Similar posts have been done on mongodb support site but it may be a pure GIS problem,so here I am ^^. My scenario is the following : I create a Point/...
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3answers
16k views

Calculating projected area of polygons with field calculator in ArcMap?

I've got a polygon featurelayer in ArcMap 10. The coordinate system of the featurelayer's featureclass is web mercator. The dataframe of the map uses an equal-area projected coordinate system. I've ...
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1answer
62 views

Don't understand error : Error in if (nchar(projargs) == 0) projargs <- as.character(NA) :

When I run two different scripts from examples (which seem to work where I took them from) I get an error in both cases. Something seems to be wrong in my general set up or something. But I have no ...
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1answer
18 views

CRS USA_Contiguous_Albers_Equal not working

I have selected the USA_Contiguous_Albers_Equal_Area_Conic, yet the map is showing a different projection. It worked when I started the project and something went wrong after I did a "print composer"....
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1answer
20 views

CRS different after r.reclass through QGIS different than source raster

According to the properties, my output raster is in a different projection than the input after running GRASS r.reclass through QGIS. Does anyone know if this is just a fluke and I can simply select a ...
3
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1answer
34 views

Configuring Project CRS to reflect degree coordinates

seems like this is a common problem, but posts with similiar questions did not solve my problem. I have close to zero GIS background so apologies for my ignorance. My goal is to extract only a ...
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1answer
49 views

Getting Borders as SVG using Peters Projection?

Is there 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 anything on my ...
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1answer
61 views

How to tranform MODIS tiles into lat/long?

I'm trying to get the vegetation index nearest to a particular lat/long. I'm getting the data from here which is 250-meter spatial resolution hdf file. The globally gridded projection is split in 36 (...
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1answer
38 views

What SRS does leaflet use when it creates new markers?

I'm using leaflet 0.7. I'm wondering what spatial reference system is used when a new marker is created? Also, how does this impact my use of maps? (I'm using leaflet .7 because of dependency ...
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1answer
33 views

Projections leaflet and OSM

I downloaded data from OSM and extract lat/lng coordinates from a user who is clicking on a leaflet map. So my program returns the coordinates where a user clicked! I am wondering what crs I need to ...
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1answer
18 views

ENVI Changes the Projection of the output

After I have finished my Object-Oriented Classification, I open my result in ArcMap and I see that ENVI changed my Projection. Now the images are really in different places.
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0answers
46 views

Grib file information to create QGIS projection

I'm trying to create a specific projection with QGIS (something like that: +proj=lcc +lat_1=69.75 +lat_2=52.87 +lat_0=61.31 +lon_0=7.665 +x_0=0 +y_0=720 +ellps=GRS80 +units=m +no_defs). I have some ...
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1answer
52 views

Differences in the longitude and latitude between a LiDAR DSM and an optical image

I've downloaded the UK's LiDAR elevation data (see below) in laz format for a specific region (Tewkesbury) from: http://environment.data.gov.uk/ds/survey#/download From that, a DSM (Digital Surface ...
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1answer
31 views

Getting LonLat of a specific location in a specific projection on osm / google maps?

How can I get the coordinates in, for example EPSG:4326 of a specific location, in either OpenStreetMaps or Google Maps?
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1answer
41 views

How to interpret cell size arcgis

I have a raster layer that has cell size(x, y) 0.008928, 0.008928. I download it from the website as 1km resolution data under WGS_84. I can not find the unit for these numbers in the metadata. Is ...
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0answers
20 views

How to resolve issue with model output in degrees and ASCII format cell size in meters when converting to a raster?

I am new to using Arc. I have data from a model output where each grid cell is 1/16 of a degree resolution. I have put the data into ASCII text format, however the header for ASCII under "cell size" ...
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8answers
495 views

Seeking introductory texts about coordinate system projections?

Even after some time working in this GIS field, I still don't have a solid understanding of spatial references, how they are projected, and most importantly, if you still need to worry about the fact ...
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0answers
14 views

How to retrieve geodetic coordinates from a geotiff in Javascript?

I believe I have successfully calculated UV space coordinates by following this formula: var size = [image.getHeight(), image.getWidth()]; var xScale = directory....
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1answer
27 views

Soviet Maps projection

What was the projection used for the Soviet Topographic Maps? http://maps.vlasenko.net/smtm50/k-37-072-1.jpg i am trying to georeference a map from Georgia. I believe the projection used was GK (3 ...
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3answers
13k views

Using ArcMap, how may I convert a shapefile to use decimal degrees?

I have a shapefile that currently uses meters as the measure for its coordinate system, but the map framework I wish to use expects decimal degrees. I'd like to reproject my shapefile to use decimal ...
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1answer
755 views

How should I work with Layers with different projections in openlayers-3?

I'm using openlayers-3.8.2. I have some ol.layer.Tile layers and ol.layer.Vector layers. The projection of ol.layer.Tile layers and ol.layer.Vector layers are different. ol.layer.Tile layers work with ...
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11 views

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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1answer
25 views

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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0answers
51 views

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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12 views

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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2answers
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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
53 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
37 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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0answers
13 views

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
714 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 ...
6
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2answers
729 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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0answers
49 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 ...
173
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11answers
62k views
0
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0answers
21 views

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 ...
1
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0answers
34 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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0answers
65 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 close,...
8
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1answer
163 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 ...
3
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1answer
96 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 ...
2
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1answer
46 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 --no-...
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1answer
1k 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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0answers
25 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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0answers
21 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 ...
2
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0answers
55 views

Getting Error 000151 from ArcGIS Projection? [closed]

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 ...
2
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1answer
38 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 ...