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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OL3 How to reproject vector layer on fly (ol 3.14)

I have a map in OL 3.14 with a WMTS in a specific epsg. I add a WMS layer in an other projection and it's ok, OL reproject right. But with a vector Layer (geoJson, in the same projection as WMS), ...
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1k views

How can I transform GCS_WGS_1984 to GCS_North_American_1983?

I need to convert a GCS_WGS_1984 data set to NAD_1983_UTM_Zone_14N. What transformation should I use?
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1answer
38 views

My point shape file having missing spatial reference information

I am using ArcGIS 10.2.2. I got a shape file with points representing spot elevations in my study area. This file has been provided by a third party institution. The coordinate system is missing ...
3
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1answer
102 views

Rotating ~90° using Two-Point Equidistant projection with Proj4

I'm trying to rotate a tif raster in R using Proj4's Two-Point Equidistant projection - I think the only way to rotate spatial geometries to custom angles. But I'm finding the operation gets very ...
2
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1answer
59 views

Calculating Geometry in ArcGIS without a Projected Coordinate System

For my project, I want to calculate the geometry of individual polygons in my layer to find area and perimeter, however it is greyed out when I try to use this tool. Beforehand, I set the data frame ...
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41 views

How does ArcGIS project-on-the-fly in an Export Data task, to a different datum and custom projection?

I need all my data in an equal area projection to for an analysis that will calculate area at the North American Scale. The projection I want is custom, it has the following settings. I will be using ...
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22 views

Unknown coordinate system produced in 1980 by Japanese company in North Philippines

I am having the same difficulty with one of the report produced in 1980 by Japanese company. The grids format also N 38,578, E 41,400. The project is 390 kilometers north of Manila. I would like to ...
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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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4k views

What is the approximate error of the Pythagorean Theorem vs. Haversine Formula in measuring distances on a sphere at various scales?

Many people when first trying to calculate distances between two longitude / latitude pairs ask if Pythagorean theorem works as an appropriate distance function. Most often people answer "no, the ...
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72 views

Reprojecting a raster file in R

Help! I have a number of rasters from different sources with different projections. I want to reproject the rasters into a common projection (Eckert IV), somehow line the grids up, and then overlay ...
2
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1answer
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 ...
2
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0answers
24 views

Raster and digitized shapefile misplaced in same projection

I have georeferenced .tiff rasters with cadastral borders and corresponding digitized borders in shapefile based on that raster. All that was done in some Mapsoft software. When I insert both in QGIS ...
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1answer
47 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 (GDA_94)...
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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 ...
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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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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 ...
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1answer
457 views

Why does map display like it is in Isometric when everything is in EPSG:4326?

I'm beginning with Geoserver and try to display a map of my country (Belgium) is an openlayer map (embedded into a MapPanel object). I've downloaded the municipalities limits from gadm.org and copied ...
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1answer
214 views

calculate distance between points crossing the antimeridian

How can I calculate the distance between two points (lon/lat) if any of the points exceeds the antimeridian (+-180 longitude)? Im using the distVincentyEllipsoid {geosphere} to calculate the shortest ...
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1answer
38 views

Reproject OpenLayers.Layer.OSM

In my map a set projection and displayProjection as EPSG:3763 and i can see my vector layers...they are EPSG:3763 Projections. Now i need a simple map behind my vector layers and i put this layer: ...
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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 ...
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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 ...
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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 ...
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77 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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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( ...
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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 ...
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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 ...
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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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 ...
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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 ...
4
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0answers
76 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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1answer
718 views

Layers are of same area but they do not overlap in ArcMap like they should? [duplicate]

For my GIS project for my class, I have downloaded several vector layers from different websites (polyline of the continental divide, a boundary polygon of New Mexico, a rivers and water bodies layer ...
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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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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. ...
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6answers
16k views

Why is the 'straight line' path across continent so curved?

This is the result of mapping the straight line path from a point in US to Poland using Distance Measurement Tool. Also, planes from Asia to US would travel almost over North Pole. Why is the path ...
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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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 ...
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1answer
958 views

What is/are the coordinate systems used in South Africa?

What are the principal datums and projections used in South Africa including the names of geodetic datums and their projections?
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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 ...
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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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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 ,-...
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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 ...
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 ...
37
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3answers
42k views

Layers with same coordinate system should align/overlap but do not?

I put 4 different layers into my ArcMap document, but only one of them will show up on the map! I should be seeing the other 3 layers as well. When I do a Zoom to layer, I can see one layer, but I ...
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, ...
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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 +...
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1answer
494 views

Openlayer plugin in QGIS, error in projection 3857 Pseudomercator

I'm using QGIS plugin Openlayer to set the background of Google satellite under my vector layer. However, even if I project my layers as EPSG 3857 (the default and only possible projection for ...
4
votes
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 ...