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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82 views

Getting village map into correct place on OpenStreetMap raster background?

Can anyone tell me the steps to display my village map (as a tif/tfw pair of files) over an OSM raster layer (from the OpenLayers plugin) in QGIS? Because every time I try my village ends up in the ...
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0answers
49 views

Problem with adding GeoJSON to OpenLayers 3

I transformed (.geojson file)from EPSG 2180 to 4326 using ogr2ogr -f "GML" -lco GEOMETRY=AS_XY -t_srs EPSG:4326 test.geojson file.geojson I would like to add to map, but I received this error : ...
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0answers
36 views

Where can I download a world shapefile with 180-degree central meridian?

Does anyone know where I could download a world shapefile that has a projection with a central meridian of 180 degrees longitude? I have found the following question that provides instructions for ...
0
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1answer
63 views

Problem with projection in OpenLayers3

I would like to add polygon geojson in the EPSG:2178 projection. The polygon should be displayed in central Europe but I see my geojson in Asia. Where have I made a mistake? Where can I find ...
0
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0answers
20 views

Layers do not overlap [duplicate]

I am new to ArcGIS. I have some layers. Three of them perfectly overlap and the fourth does not. I have tried with the Projection tool and I have tried so many things and nothing. When I check the ...
7
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1answer
283 views

Understanding difference between Coordinate System and Projection?

Can somebody please explain what is the difference between the Coordinate system (WGS 84 for example) and a Projection (Universal Transverse Mercator for example)? What is the difference between a ...
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0answers
47 views

Formula for Nicolosi Globular Projection

What is the formula for the Nicolosi Globular projection? In other words, what is the function that maps the coordinate (φ, λ) on the sphere to the coordinate (x, y) on the plane? You can assume ...
2
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33 views

Converting u and v from WGS84 to NZTM2000 - Do I need to do vector conversion?

I have u and v wind component values in latitude and longitude in WGS84. I want to convert this to NZTM2000. I've converted the lat/lon in ArcView - (and will try in R) - but do I need to also do some ...
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1answer
62 views

Changing coordinate system says that geotransformation is invalid?

I am planning on using the MODIS burned area products which were produced by Maryland University. These come as either polygons or rasters. In the user guide it says A shapefile version of the ...
13
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2answers
564 views

Which projection is this data in?

I received a shape file for my project from an agency and was told that they always use UTM. However, the values have too many digits for being projected in UTM. min max x 32507319 ...
2
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1answer
17 views

WFS Filter performed before or after reprojection?

I'm trying to perform a WFS filter with a polygon in EPSG:3031, (the native projection is EPSG:4326 I think). And I'm aware that WFS/GeoServer supports reprojection on the fly. But will the features ...
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0answers
55 views

Determining printed map projection?

A friend of mine is working on a small project to map receding North Pole summer sea ice minimums by decadal averages on a wall-paper map. Unfortunately, it seems as though the map projection for ...
4
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4answers
238 views

Get a coordinate system from raster file

I am writing a code to loop through all the files in a folder and reproject them, using a raster as the spatial reference. I have a suspicion that there is a different way to get the coordinate system ...
4
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0answers
75 views

How to choose the EPSG projection?

Up until now for reprojection of my WGS84 vector (.shp) and raster files (.tif), I have been using EPSG projections based on vector/raster central point's UTM zone. But what happens if the envelope-...
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0answers
88 views

Geographic vs. projected raster cell size area

I am wondering the best way of knowing how to define the area of each raster cell in global data. Specifically, I downloaded all ~400 tiles of MODIS land cover data, mosaiced them into one, and now am ...
1
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2answers
145 views

Coordinates not displaying in UTM

Mac OS 10.9.5; QGIS 2.8.4-Wien; offending data here I want to calculate the centroid of a polygon in meters. However, I cannot get QGIS to display in UTM and I cannot transform/project the data to ...
2
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0answers
29 views

OpenLayers measurment path in 31700 projection

I have this code who works great for distance measurment on 900913 projection with 4326 display projection (bing maps + layer WMS): measureDistanceControl = new OpenLayers.Control.Measure( ...
1
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1answer
112 views

Getting inaccurate results converting from New York State projection to NAD83 with Python's pyproj

I've been trying to do a standard coordinate translation between New York State Long Island (ESRI:102718) and latitude/longitude (EPSG:4269)...but I keep getting the wrong lat/lng results. I don't ...
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0answers
45 views

Correcting for offset

I have a shape file with RTK measurements as a line feature, which more or less corresponds with visible features in a raster layer (shaped as lines). These measurements however are not accurate ...
0
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1answer
33 views

How to read info from the CRS? [duplicate]

I'm struggling to understand how the geo projections work in practice. The info a the CRS is as follows: {'ellps': 'WGS84', 'no_defs': True, 'proj': 'longlat'} Does it mean that the coordinates are ...
4
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1answer
212 views

Map projection classification - Tissot's indicatrices are perfect circles, but the projection is not conformal

Recently, led by the perfectly circular shape of the Tissot's indicatrices all over the projection plane, I have concluded that a particular projection is conformal. However, after calculating angular ...
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0answers
23 views

How to work with a shapefile that has no projection information? [duplicate]

In a shapefile I'm working with there is no information on the projection used. That is, no .prj file. Is there a hack/alternative way of determining what coordinate system the data is in?
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0answers
23 views

Geodesic replacement of coordinates [duplicate]

With a updatecursor I can move vertex to a new location and modify polygons. For a simpele example I tried to move the world, see image. The black lines are the 'edges' of world (180,90 -180,-90 ,-...
3
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1answer
77 views

Way to Shrink Alaska and Hawaii for “Stereotypical View”

Is there anyway to shrink Alaska and Hawaii to create a map that looks like the stereotypical map with AK in the corner, etc.? I thought about trying to isolate AK and HI in their own layers and then ...
0
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1answer
62 views

Reproject non-earth to ITM/ICS

I'm trying to convert MapInfo, non-earth projection, layers with data in ITM or ICS (Israel coordinates in meters). When I do so through Universal Translator with converting to SHP and back again, ...
0
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0answers
27 views

EPSG:4978 or others for Distance

Usually when I have been calculating distances I project to the system which has the tightest crop around my points e.g. for the UK #http://epsg.io/27700-5339 (accuracy: 1.0m) uk = '+proj=tmerc +...
4
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1answer
67 views

Why can't QGIS handle the Kavrayskiy7 projection although it is supported in proj4?

I'd like to make a world map using the Kravayskiy7, however QGIS seems to be unable to handle the projection, even though it is supported by proj4. 704900 (as is the EPSG for kav7) is not listed in ...
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0answers
19 views

In ArcMap, how much is a Zoom Out click [duplicate]

In ArcMap, when I zoom out (or in) a single mouse-click (not dragging a rectangle, just a click), what is the change to the ratio? If it is different between coordinate systems please explain it on ...
4
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1answer
54 views

Wrong shape display with North_Pole_Azimuthal_Equidistant projection

I need to create a map that displays the breeding and wintering ground of a bird species that has a circular arctic breeding distribution and winters in Africa. The map should lool pretty much like ...
0
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0answers
30 views

Trouble with Calculate Geometry in ArcMap 10.2? [duplicate]

I got a "Federal Lands" shapefile from nationalmap.gov. I clipped it down to the geography I am focusing on (a few counties in eastern California). I am trying to use the "calculate geometry" tool to ...
1
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1answer
55 views

Error distance for coordinate transformation (to WGS84)

I have a dataset with mostly EPSG:31255 and wanted to convert it to WGS84. I now had to realize that the results are up to 100m off when I plot them on a map or just enter the resulting lat lon in ...
0
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0answers
61 views

Why is the project tool in ArcGIS (ArcMap) for desktop throwing the “invalid geographic transformation” error?

I'm trying to reproject a point shapefile from ITRF92 to WGS84 UTM ZONE 14 NORTH. On the geographic transformation input field, I copied and pasted the following geographic transformations from the ...
3
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1answer
99 views

Plotting netCDF4 data with the right projection

I guess this will sound simple to you but I just cannot get the right plot within R. I have a netcdf4 file and would like to visualize it within R just like I would do in QGIS and ArcGIS. sample data ...
3
votes
3answers
113 views

Projection issues with Leaflet - polygon appears off

Using Leafletjs to upload coords from a json file as a polygon. The original coordinates are Vicgrid94(3111). I used QGIS to change the projection to LatLng (4326). When I load the points onto my ...
3
votes
2answers
72 views

How to calculate area in sq m - troubleshooting projection issues in a global dataset in QGIS

I am using QGIS version 2.12.3. I have 3 polygon shapefiles: A, B and the intersect of A and B, which we can call C. All I want is to add a field to the attributes table of each shapefile giving ...
2
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1answer
45 views

Encode an azimuthal equidistant projection in NetCDF conversion

I'm trying to do Azimuthal Equidistant in CF-compliant NetCDF, but I didn't get the correct projection. If you compare the first two information (gdalinfo) you see there is no AUTHORITY and also ...
1
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1answer
113 views

Difference in EPSG:28992 (RD/Amersfoort) definitions

I need to do some projections between WGS84 (EPSG:4326) and the Dutch RD system (EPSG:28992) in JavaScript. I use Proj4js for this. When adding the definition from spatialreference.org I noticed a ...
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0answers
24 views

Does sinusoidal projection have constant scale factors in all directions?

I know that no map projections preserves all distances. However, looking at the definition of the sinusoidal projection: y = R * phi x = R * lambda * cos (phi) , where R is the radius of earth. ...
2
votes
1answer
59 views

Arcobjects Assign projection transformation to layer file in VB.net

I want to be able to transform a layer from WGS1984 to OSGB1936. I created a tool that extracts layers from several folders on our company network folders, using check boxes that user clicks. One of ...
0
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0answers
18 views

Projecting the Coordinate Systems of layers but one layer doesn't show up with the rest of the layers

I have data from two folders I am working with. Each folder contains shapefiles. The shapefiles in each folder need to have their coordinate systems projected to NAD_1983_UTM_18N. There are 6 ...
3
votes
1answer
66 views

Vincenty or (Project + Euclidean) for accurate distances

I posted a similar question on stackoverflow, however was directed here for more help. If my main goal was to calculate distances such that my error was minimised to the nearest metre assuming that ...
1
vote
1answer
188 views

Convert to lat-lon coordinates GDAL

I have a netCDF file and would like to convert it to LAT-LON coordinates. 1) I do not know the projection in the file but from the website of the data provider, the data is on a polar-stereographic (...
0
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1answer
122 views

Project NetCDF file using GDAL or QGis

Can I project a NetCDF file with the help of GDAL or QGis? The file info is: gdalinfo c:\tomcat-6.0.36\webapps\ncWMS\layers\RAIN_MM_1hour_ac.nc Driver: netCDF/Network Common Data Format Files: c:\...
0
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1answer
19 views

calculating ratio of areas on a sphere

I have 2 shapefiles and after identifying their intersections I'd like to know the ratio of intersecting areas, e.g. a given shape S in file1 intersects with shapes (x1,...,xn) in file2 with ?...
15
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1answer
1k views

Can Mars be mapped in ArcGIS

Can I use ArcGIS to map planets in particular Mars? Where would I start in terms of basemapping and projection?
3
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0answers
99 views

How to calculate false easting/northing for Lambert Conformal Conic projection

I'm defining a new GRASS location using the Lambert Conformal Conic projection. My understanding is that the values for the standard parallels and central meridian are dependent on my area of interest;...
1
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1answer
62 views

Correct Projection for calculating centroids of a group of points?

I have a long list of points covering all of North America for which I would like to calculate the centroid (by grouping points based on the "Name" column). My approach is to take the WGS84 co-...
1
vote
1answer
63 views

What projection to use in POSTGIS for LAT/LONG and 'contains' queries

I would like to store latitude / longitude information in a POSTGIS database. I will need to query that data with simple contains query (for display on a map, so the bounding will be simple box) and ...
1
vote
1answer
88 views

projection (WGS84, UTM) issue

I have a question about projections. I have a hillshade raster with UTM 31N projection (I reprojected this from WGS 84). I also have a satellite image that I need to georeference. For georeferencing I ...
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2answers
64 views

Projection for using ArcGIS as CAD [closed]

I want to use ArcGIS to map my apartment. How can I create a projection file (with which parameters)?