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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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
232 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 ...
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46 views

GPS point elevation vs Contours layer elevation

I have some survey grade GPS points whose elevation is approx 55 feet lower than my contours layer elevations. I am using 1 ft contours and comparing point elevations with contours in the same ...
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3answers
261 views

What is the altitude difference between WGS84 and NAD27 Zone II?

I have a point cloud in a piece of software and have exported the point in both WGS84 and NAD27 State Plane California Zone II (in US survey feet). The WGS data looks like this, with elevation in ...
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308 views

Map projection process for three-dimensional point cloud

I have some points given in ECEF coordinates (or LatLongAltitude based on WGS84, which is interchangable in my understanding). Currently I am working on a mapping software which allows to visualize ...
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28 views

Project (Data manager) plus Add XY results in new data being rotated

I have point data in decimal degrees. When I want to convert to local UTM data I have going through the usual Project (Data Manager) to project from LAT/Long to UTM and then when I add XY to the new ...
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42 views

Batch reproject shapefiles in subdirectories

I have a catalog tree and in every folder I have a number of shapefiles, images and mxd files. The shapefiles are all in Greek Grid projection system (EPSG: 2100). What I want to do is to batch ...
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132 views

Why does the OpenLayers plugin override the predefined projection?

What I am trying to say is: You import a shapfile into an empty QGIS and the QGIS environment gets the projection system of the imported shapefile. You import another shapefile into QGIS. The ...
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32 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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37 views

How to get a mercator projection from a “disk photo”

I'd like to build a real 3d globe of Pluto using latest images made available from New Horizons. I know how to convert a mercator projection into a "12-gores" projection, suitable to be glued over a ...
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109 views

Are ArcGIS' UTM zone designations simplified?

I was recently given a document showing the UTM zones as they appear over the whole Earth. Each zone is 6 degrees longitude by 8 degrees latitude. A numbering system proceeds from 1 to 60 from -180 ...
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57 views

What is the type of EPSG of longitude/latitude (not Point) co-ordinates?

I want to know that what is the type of projection (900913, 4326 or so on..) of long/lat co-ordinates. I happen to come across a slight confusion while querying planet_osm_lines when I dump ...
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144 views

Shapefile extent units in decimal degrees but values in meters

I have a shapefile that had its geographic coordinate system defined as the projection NAD 83 UTM Zone 18. The scale of the layer was correct but it was at the wrong point in space. I redefined the ...
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3answers
103 views

How to overlay a map of Europe on a map of Australia?

I'd like to overlay the cities of Europe on Australia for distance/size comparison purposes using QGIS and I'm wondering how best to achieve this while preserving distance between the European cities? ...
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1answer
290 views

Create Circle and Marker on Click in OpenLayers

I want to create a marker and buffer around it with a given radius on map click event. Marker is displayed successfully but the polygon doesn't display. I guess there is problem in projection setting. ...
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51 views

Setting units for arcpy fishnet tool, given unprojected input

I'm trying to use arcpy to create a grid over each of a large number of metropolitan areas across the US. I'm iterating over each metro and trying to create a grid over each one using the "fishnet" ...
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49 views

Getting wrong values trying to convert to a latitude longitude system

By using listgeo I got the following information: PCS = 31468 (name unknown) If I am not mistaken this translates to DHDN / 3-degree Gauss-Kruger zone 4, and by using this site I got a proj4 ...
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1answer
134 views

Using OSGB (ESPG: 27700) projection in Openlayers with MousePosistion

I am trying to display Ordnance Survey Grid references (ESPG:27700) on a set of BaseMaps with the MousePosistion control. From looking through the OpenLayers samples and this forum samples I have ...
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1answer
47 views

Choosing projection for calculating 2D 3D area in New Zealand?

I'm trying to use Surface Volume tool in ArcMap to calculate 2D and 3D area of a catchment. What would be the best projection to use and how do i check the maximum error of the estimation?
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1answer
118 views

Tilted projection in QGIS

I'm trying to add tpers projection as a custom projection in QGIS 2.10.1 In the Custom crs dialog I'm adding the proj.4 text: +proj=tpers +h=500000000 +lat_0=19 +lon_0=99 +x_0=0 +y_0=0 +a=6371000 ...
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30 views

Projection Discrepancy

I'm creating a system that pulls Longitude/Latitude data from the MapQuest hosted Nominatim service. I'm using OpenStreetMap/OpenLayers to display markers on a map. In order to compute the location to ...
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1answer
107 views

What projection to use to get a game map into QGIS?

I have built and maintain a SWTOR game map atlas. At the moment, it's all static jpg maps, but I would like to get the info into an actual GIS software to get more functionality and make my website ...
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39 views

reproject satellite orbit values from irregular grid to regular grid

I have a ncdf file containing measurements covering a satellite orbit. The ncdf contains the corresponding latitude / longitude fields but they ar irregularly spaced. I tried rasterizing the values ...
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32 views

QGIS to Leaflet Projection Weirdness

I've been using the mmqgis tool to create a hex grid. It loads up in QGIS looking good, but when I save it as geojson and load it up in leaflet it gets stretched (see attached). It starts life as ...
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42 views

ArcGIS: Goode Homolosine Projection and Inconsistent Extents

I recently posted about a problem in ArcGIS using the Goode Homolosine (Land) projection with the Project Raster tool HERE. The problem was related to a bug with that tool, and a workaround solution ...
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123 views

Copy GeoTIFF metadata to TIFF using ArcPy

I have conducted some image manipulation on GeoTIFFs in a program and the resulting TIFFs now have no spatial information attached. Their x,y origins are (0,0). Since these processed images are of ...
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1answer
78 views

How to center a user-defined CRS on an area of interest?

My study extent in central Iran straddles two UTM zones (39 and 40): I would like to create a user-defined CRS in Transverse Mercator projection with central meridian inside this area. Through ...
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160 views

Projected raster data has inconsistent extent but not shapefile

I want to calculate the average value of a raster file within each polygon boundary of my shapefile. Because I want to preserve area I wish to use the Goode Homolosine (Land) projection. The original ...
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1answer
117 views

Proj4 for EPSG3857

I am using leaflet and the R library sp. The CRS from my leaflet map is EPSG3857 - WGS84 Web Mercator. I am retrieving the coordinates of my current map view with getBounds(). For further calculations ...
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1answer
70 views

GDAL -SQL or -where options

ogr2ogr -overwrite -t_srs EPSG:3978 -f "ESRI Shapefile" -sql "SELECT * FROM 'Layer Name' WHERE FIELD_NAME = 'A CLASS'" dst.shp src.shp help me out here - looking to 1) reproject a shape and 2) ...
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86 views

Converting from flat earth to WGS84 with python

I'm looking to move from basic 2d Cartesian coordinate system into WGS84. I know my starting coordinates, however all intermediate points are x/y/z points. of an origin 0,0,0 . Mathlab has a ...
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3answers
101 views

How to find the extent of (many) EPSG CRSes?

I want to map the geographic extents / bounding boxes of a lot of EPSG CRSes. At least, those with a rectangular geographic extent. For example, take epsg:2004, visiting that page shows the extent ...
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2answers
173 views

How to define a 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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1answer
45 views

How to convert shapefile of India into a system with longitude and latitude system?

I have two shapefiles of India. One is without PoK and other is with Pok. I want to convert the shapefile of India with PoK into a co-ordinate system with longitude and latitude (same as without PoK). ...
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79 views

Matching d3.js geo projection with pyproj Proj4

I am having trouble figuring out the correct notation for Proj4 projections with pyproj. I got the following projection in d3.js and I want to match it with pyproj on my backend to send a background ...
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74 views

Project Raster: Resampling

Is this (optional) resampling technique in the Project Raster tool only being used if changing the grid resolution (cell size)? Or should I always select bilinear (or cubic) for continuous data even ...
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1answer
239 views

Projecting a world map on 6 segments to print on ball

Working with QGis and data from Natural Earth I would like to prepare a world map (1:50 000) for a globe that can be printed in 6 segments, which glued together build a ‘sphere’ (ball) according to ...
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67 views

Geographic Coordinate System NAD 1983 vs Projected Coordinate System NAD 1983 & Projections

I am working on a project utilizing free data from http://www.pasda.psu.edu/, specifically data from PennDot, 2015 Pennsylvania County Boundaries ...
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5answers
292 views

Fisheye-like projection

I need a special projection for the purpose of effective presentation on a poster. I'd like to present the study area (Czech republic) in a context of whole Europe in such a way, that the Czech ...
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1answer
434 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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2answers
159 views

How can I convert points in EPSG:2956 to EPSG:4326 with pyproj?

I have some points in EPSG:4326 -110.28879750 64.46310187 405.49938863 -110.28879359 64.46310086 405.45967110 -110.28880175 64.46310446 405.93823604 -110.28880245 64.46310258 405.48060850 ...
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2answers
245 views

Why do I get correct area and intersect area when use wrong projection?

I need to calculate areas and intersection areas for polygons (some real geographical objects like lake, city, country, e.t.c.). Polygons located in California, New Zealand, Russia.Anadyr, Sweden All ...
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1answer
70 views

How to get geodetic area? rgeos::gArea doesn't seem to work. Or area-preserving projection

I need to get an area of different polygons at continental scale (like third of Africa etc.). Usual functions like rgeos::gArea work only in the projection units. Is there any function which works ...
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61 views

raster data and polyline shapefile do not line up

I am working on an ArcMap .mxd encompassing the state of new mexico. I have a shapefile of the state boundary with the following coordinate system GCS_North_American_1983 WKID: 4269 Authority: EPSG ...
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448 views

Converting from kilometers to degrees distances?

We have geometries in a Postgis database with SRID WGS84 and we have found lookups directly in degrees to be much faster than in kilometres, because the database can skip the projections I would ...
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1answer
32 views

Measuring different values in latlong Geotiff whether OTFR enabled or not

I'm using a GeoTiff file in QGis that has no projection per-se (it uses lat-long coordinates) and WGS84 datum. Further it has an x pixel size of 2.40475e-07 degrees and a y pixel size of ...
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1answer
33 views

Map Projection - Why don't we draw things out

I have been reading about different map projections and kind of understand where the problem lies. And also, most of the problem was that the old cartographers did not have any other tool other than ...
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73 views

How to choose a projection for area measurement on building to continental scales?

I have many geographical objects described as polylines, polygons, multipolygons. All objects are in WGS84. Object could be: a building, stadium, park, street, highway, city, state, even country and ...
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1answer
44 views

Atlas with different projections in QGIS

I have created an atlas -- i.e. a map with a layer defining some regions of interest -- in QGIS. I can render maps of each region using the "atlas" feature of the print composer, but I want to show ...