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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Using a Local Datum Plane (LDP) scale factor within ArcMap?

I have a CADD drawing that uses a Local Datum Plane (LDP) scale factor of 0.99991199. When I add the drawing to ArcMap without taking into account the scale factor, the drawing appears to the east of ...
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44 views

Correcting the shift of MapInfo data in QGIS 2.6 (and earlier too)

I often receive multiple .mif or .tab files and view them alongside shapefile layers in QGIS 2.6.1. Dragging one of the .mif files from a Windows Explorer window into a QGIS window will display the ...
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28 views

polygon will not project correctly into project

I have a project that one shapefile( I believe created in arcgis) layer mysteriously quit projecting correctly. I am using Q 2.6.1 On the fly is enabled, coord system set at EPSG:4326 - WGS 84, when ...
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2answers
52 views

How do I get UTM projected areas from a shape file created in QGIS?

I create a polygon (or point or line) .shp file in QGIS and it is automatically saved as WGS (as I understand, correct me if I'm wrong). That is fine by me despite being a bit inconvenient. Then I ...
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1answer
160 views

Reprojected Shapefile does not align with Openlayers Plugin [closed]

I am based in NSW, Australia. I have a shapefile that when I underlay with the openlayer plugin (google satellite), the shapefile is skewed despite all my efforts to correct it. I changed the ...
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0answers
115 views

Show a kml (which uses longitude and latitude EPSG:4326) in “google/OSM” projection (EPSG:3857) in open street map

I am showing a kml layer, over OSM. The points in the kml are latitude/longitude (EPSG:4326). I don't have to convert any points or anything, it all just works. Great! Now, the client also wants to ...
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2answers
648 views

Ortho Projection produces artifacts

I`m trying to create a sphere-like view using qgis and the "world from space"-projection http://spatialreference.org/ref/sr-org/6980/ (essentialy an ortho-projection). ArcGIS wraps the shapes ...
2
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0answers
167 views

Working with AIG Raster format in ArcGIS for Desktop?

I downloaded a specific layer which has the format "AIG" as you can see in the screenshot. It has no projection so I applied "Define Projection" on it. I searched for the projection and found the ...
2
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2answers
107 views

Digitized Shapefile manually using wrong projection: how to fix it?

I have a raster in correct projection. I used shapefiles, and marked objects (manually), but I found out that my vector layers have different projection, so they have different size and position. Is ...
2
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0answers
21 views

How can I get a web-hosted kmz file to project correctly when added as a layer to an arcgis online map?

I have a kmz file hosted on dropbox that I would like to display in a map through arcgis online. The kmz file was generated from an esri grid raster. I have tried altering the raster projection prior ...
2
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1answer
159 views

How to reproject vector data?

I am evaluating QGIS with a view to visualize and manage geological exploration data. The information is currently stored in different local coordinate systems that I am looking to overlay with ...
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6answers
1k views

Real-world example of Affine Transform?

From the Wikipedia article: In geometry, an affine transformation or affine map or an affinity (from the Latin, affinis, "connected with") between two vector spaces (strictly speaking, two affine ...
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0answers
67 views

Projection problems when importing .kml from Google Earth to QGIS

I want to open several points that I exported from Google Earth as a .kml in QGIS for further use. I can import the data and the points are displayed but something must be wrong with the projection as ...
5
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2answers
670 views

Transformation parameters for Everest datum to WGS84

I have a shapefile with the following projection information: ...
8
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3answers
225 views

What coordinate system is this netCDF raster?

I obtained a netCDF raster file, but I couldn't get any metadata to get the name of the coordinate system the raster has been built on. The raster itself doesn't have any coordinate system embedded. I ...
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1answer
50 views

I can't get my OpenLayers radar overlay to display correctly

I've tried to overlay a radar image on my map so that I can show the current radar for the United states. However, whenever I load the map, I can't seem to get the projection to look correct. Here's ...
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0answers
65 views

Is there a formula for calculating 2D map distance from 3D information?

Using ThinkGeo, I have a Lat/Lon coordinate, and a distance of .1 miles. The .1 miles represents the radius of a circle and I'm trying to draw this radius around the lat/lon coordinate. The map units ...
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1answer
118 views

How to update projection of layers in Geoserver using gsconfig

Im using following code to find projection of layer from geoserver.catalog import Catalog cat=Catalog("http:// localhost:8080/geoserver/rest") myResource = cat.get_resources(store='storeName', ...
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1answer
30 views

Why Geowebcache is locking all system?

My story is like this about geowebcache. I am useing geoserver 2.5.x and GeoWebCache version 1.5.2, build 1.5.x. OS is ubuntu. I can not found geowebcache.xml file in server. But there is a file ...
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2answers
50 views

I am looking for a direct long. to X lat to Y map of earth

Occasionally I like to drop raw coordinate data into excel and do a scatterplot. It comes out quite a bit like cylindrical projection but not quite. The distortion near the poles is a bit more ...
4
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2answers
250 views

Why is the Google Maps circle shape not matching to the distance calculated with PostgreSQL?

I am running a PostgreSQL 9.1 Database with PostGIS 1.5 extension. Several coordinates are stored in there with type GEOMETRY (SRID 4326). I'm building a web-application with Google Maps Javascript ...
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1answer
153 views

Scaling x,y coordinates in proj4

This question was asked before, but without answer. Let's say we have mercator map with given resolution (for simplicity in centimeters). Now let's get coordinates of (lat,lon) = (50, 15): $ proj ...
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1answer
87 views

Overlaying two shapefiles and projecting one of them from Geographic to Projected Coordinate System? [duplicate]

I am trying to project a shapefile which is in Geographic Coordinate System i.e. Geocentric Datum of Australia 1994 to a Projected coordinate system i.e. Map Grid of Australia Zone 55 using GDA 94 ...
2
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1answer
144 views

Reprojecting MODIS Ice Sea Temperature products with gdalwarp

I have problems projecting MODIS Ice Sea Temperature (IST) products to EPSG:3031 (Antartic Polar Stereographic) using gdalwarp. The product I'm working with is MOD29E1D, documented here, p33: The ...
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1answer
81 views

Openlayers 3 circles from geojson not working with layer tile source different from TileWMS

I am working with openlayers 3 with a layer from mapbox or openstreetmap and I need to draw some circles on it. I am able to print the circles with a view with a projection EPSG:4326, but then I have ...
3
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0answers
44 views

Is there a way to expose Spherical Mercator Lat Lon in Google Map API?

The map tiles in the Google Maps are in Spherical Mercator projection (srid 900913), but in the API the methods report coordinates in Lat/Lon WGS84, e.g. map.getCenter(). Is there a way to return the ...
3
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3answers
227 views

Which equal-area projection to use for UK?

I have a bunch of UK polygons that are saved in my PostGIS database as WGS84 projection. I would like to calculate the area of these polygons using st_area. According to this answer I can save these ...
3
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2answers
3k views

Meridian convergence. True north, magnetic north and grid north

I'm having difficulty wrapping my mind around meridian convergence, the horizontal angular distance between true north and grid north. Say I want to determine if a feature lies to the east or west ...
3
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1answer
352 views

Openlayers 3 WMS Projection

I am working with both EPSG:4326 and EPSG:4230 in OpenLayers 3 and I am using my WMS service which only supports EPSG:4326 maps. What I need to do is show a map in EPSG:4326 and transform it to ...
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1answer
37 views

Coordinates freeze when I give a projection

I have recently begun to use arcmap and needed some guidance on a problem that I am facing. I have a district shape file with 200 districts with geographic coordinate system: GCS_WGS_1984. I need to ...
3
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1answer
29 views

Equatorial Scale

I have seen Equatorial Scale written along with the RF on the World Map in many Atlases, for eg., "Equatorial Scale 1:95 000 000". What does this Equatorial Scale mean and what is the significance of ...
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1answer
38 views

Parameters of Normal vs. Transversal cylindrical projections

I need to parameterize a cylinder that cuts the ellipsoid. One time in normal case   (eg. like Mercator) and one time in transversal case (eg. like Transversal mercator). So, in normal case the cut ...
2
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1answer
235 views

using PostGIS to calculate distance of a route over a large area

I'm new to PostGIS and looking to measure the distance of the Pacific Crest Trail which spans western North America from Canada to Mexico. I have a data set containing the lat lon and dates from GPX ...
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2answers
33 views

Unknown Coordinate System Cadastral?

I have point data from a proprietary source that came in a coordinate system I do not recognize. Here is an example: Lat: 35205357 Long: -11.15933 It looks like a combination of UTMs and ...
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2answers
56 views

How to link a shapefile with points to a shapefile with lines?

I have a shapefile with points (nodes) and a shapefile with lines (pipeline) which I have extracted from a water distribution network. I have been able to transform the points into the right ...
1
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1answer
84 views

QGIS 2.4.0 CRS reprojection creates empty files and goes generally nuts

I consider myself an intermediate GIS user but keep running in a problem with the newest QGIS version I cannot fix and wonder if it may be a bug or if I am just too stupid. The problem mostly centers ...
9
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2answers
666 views

What happens to feature class when importing to feature dataset?

I am creating a model that needs to ensure that all input datasets end up in the same coordinate system (among other things). I was originally going to batch project all of the datasets whether they ...
9
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3answers
280 views

A global, grid-like projection for creating heatmaps

I'm putting together an application where I need to create a vector grid which will be used to store and display a heatmap. It has the following requirements: Can cover the entire planet. The vast ...
0
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0answers
29 views

Projection of COSMO-EU?

I have data points of COSMO-EU data stored in WGS84 coordinates. Now I try to transform them into coordinate system where the points becomming arranged to a regular grid. Does anybody knows the Proj4- ...
1
vote
1answer
80 views

Is there a way to change the QGIS default CRS?

I'm working in a UTM projection and bringing in dxf layers from a different program. The dxf files are all in the correct UTM coordinates already, but when I bring them in I need to change the CRS to ...
0
votes
1answer
63 views

Creating a spatial reference in arcpy from projection name

I am using ArcGIS 10.2.2, Python 2.7. I want to create a spatial reference from the name of a projection, e.g. NAD_1983_BC_Environment_Albers, using the arcpy tool ...
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1answer
28 views

why am I getting a horizontal solid strip when projecting large image?

I am using Mapnik to create tiles on a tile server. I'm depicting sea level rise in North America using SRTM data, and it works fine in most of the continent. However, when zoomed out in my browser ...
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1answer
34 views

Converting datum?

I need to measure the distance (with the ruler) of points from two different layers. However, one layer is NAD83 and the other is NAD27. I also have a standard ESRI basemap downloaded. The issue I ...
2
votes
1answer
53 views

Python Geospatial Development Error

I'm working through some examples in the Python Geospatial Development book by Erik Westra. On page 439, about setting up a tile map server, he gives the following code for calculating a bounding ...
2
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2answers
89 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 ...
5
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2answers
9k views

Coordinate system and projection for georeferencing Google Maps image in ArcGIS Desktop?

I have saved Google Maps image (not Google Earth) of area at latlon(17.692437,83.218689) by some method in jpeg format. It is an exact snapshot of the Google Maps. Now I need to geo-reference it to ...
1
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1answer
99 views

Definition of the WGS 84

Hi i'm having some trouble getting the following things straight with , does this make sense? EPSG:4326 WGS84 Coordinate system: WGS84 Datum/Ellipsoid: WGS84 Projection: longlat
3
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2answers
277 views

Influence of the scale factor on the projection

I'm currently reading documentation about map projections to understand the source code of the Proj4 project. The scale factor is named in a variety of sources I read. This sources explained its ...
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0answers
51 views

How i can have the same xMin,yMin for vector files in Qgis 2.4

i have a .shp file(polygon) in EPSG:2100 - GGRS87 / Greek Grid and an other .shp(points) in the same system(EPSG:2100 - GGRS87 ) but different xMin,yMin. The first has xMin,yMin 583309.00,4152885.94 ...
2
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2answers
94 views

Is there an algorithm for transforming from CGCS2000 to WGS84?

Is there an algorithm that supports transforming from CGCS2000 coordinate to WGS84 coordinate? CGCS2000 is China Geodetic Coordinate System 2000. Any advice would be thankful!