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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How do I convert a TIF to EPSG:3857

I'm trying to convert this TIF to EPSG:3857, but when I run: gdalwarp -of GTiff -s_srs epsg:4326 -t_srs epsg:3857 -co "tfw=yes" original.tif converted.tif I just get a black TIF do you know what I ...
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76 views

How to prevent cross-world lines in ggplot world map?

I'm having issues displaying 'great circles' paths and polygons in ggmap, an extension of ggplot2. Please enter the following code to replicate my issues: ...
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45 views

Empty shapefile after project tool in a for loop

I am running a for loop to process a years worth of data. The entire script runs fine for the first run through, but when it runs again (when date is 1/2/2013), I get the following error: 'NoneType ...
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2answers
483 views

OpenLayers WMS - TypeError: this.resolutions is undefined

I'm trying to setup a map with WMS and WFS Layers by using Geoserver. However, when I'm combining WFS and WMS (with some Google basemaps) together in one map I got following error in Firebug: ...
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5answers
3k views

Calculate distance in km to nearest points (given in lat/long) using ArcGIS DEsktop and/or R?

I have two point datasets in ArcGIS, both of which are given in WGS84 lat/lon co-ordinates and the points are spread across the whole world. I would like to find the nearest point in Dataset A to each ...
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1answer
53 views

Why does ArcGIS Online project my files right where they should be but, ArcGIS for desktop does not

When loading shapefiles into Arc Map 10.2.2 I get the message saying "unknown spatial reference", then my files are not projected where they should be and are usually too small to see regardless how ...
2
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1answer
29 views

Reprojecting from Wagner VII using QGIS

I have a shapefile in Wagner VII projection (well, the proj4 string really only is: "+proj=wag7 +datum=WGS84 +units=m"). I'd like to reproject it to WGS84 (EPSG:4326) using QGIS 2.6. However, when I ...
7
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94 views

Best practices and examples of web maps of polar regions

I am looking for examples of web maps focusing on polar regions (Arctic or Antarctic) preferably using a polar projection. What could be best practices to follow for such web mapping applications? Any ...
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206 views

Show map using esri leaflet, with 4326 spatial reference

I have this MapServer http://geoservices.big.go.id/arcgis/rest/services/RBI/Rupabumi/MapServer It turns out it uses 4326 spatial reference. I want to present it using leaflet, my code so far: ...
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325 views

Projection to use with satellite image from Google Maps / Earth

I'm very new to anything concerning GIS so please forgive me if this question has been asked before, but I assure you, I've been trying to find an answer for quite some time now. Of course it is ...
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22 views

Convert height Geoid EGM96 to ellipsoidal?

I'd like to convert the height data which is in EGM96 to Orthometric projection. Perhaps there are tools, like ArgGIS (I cannot find if ArcGIS can do this), or any formula that may help me.
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80 views

How to change the projection of the base layer of a tile map?

Normally, we change projection of vector data for displaying it over a Google base map. Is it possible to change the projection of base image tiles map? If yes, how we can do that? Any reference or ...
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2answers
150 views

Wrong projection high quality shapefile for the coastline of Helsinki region (Finland)

I did some spatial interpolations in R and I need a support for those. Looking for shapefiles online the best I could find was and it looks really horrible, the same area in ggplot looks like . I ...
2
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1answer
26 views

Raster origin is incorrect, does not properly overlay with vector in same CRS

Two layers, both allegedly WGS84, one vector layer of the Midwestern US, one raster layer with coverage of the entire US. The vector layer renders correctly (coordinates are correct), but the raster ...
2
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3answers
39 views

Change projection didn't change position in a vector shape in qgis

I got a shape of points and when i save it with another datum and open it again, it stays in the same position. I was hoping for a slight change in position when save from epsg:5361 to epsg:32719.
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1answer
33 views

Partial loss of projection data converting to MapInfo File with OGR

I'm trying to convert some data from ESRI Shapefile to MapInfo TAB format using ogr2ogr. The data is projected using the British National Grid (EPSG:27700). The output file is valid, and the geometry ...
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0answers
45 views

GeoTiff using GDAL

How can I project a tiff using the position of the four corners where the picture have to be placed ? The tiff file has no georeference or projection information I have got a grid with values of ...
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3answers
806 views

Creating spatially projected polygon grid with ArcMap

i need to create a grid with 1x1 square kilometres cells in ArcMap. The operation located in Data Management Tools -> Feature Class -> Create Net is almost what i need but in the parameters, i can't ...
8
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1answer
307 views

Using customized Coordinate System for Archaeological site data

I don't know so much about coordinate systems... In my office we use to deal with spatial data coming from archaeological sites. Each site has its own x-y-z coordinate system (GCS). Three simple ...
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5answers
5k views

How can I measure area from geographic coordinates?

If I have polygons in geographic coordinates (WGS84), how do I measure the total area each takes on the surface of the earth, taking into account the curvature of the earth?
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1answer
45 views

How to transform this PostGIS type of projection to EPSG:900913 in OpenLayers?

I have transferred this kind of projection from this type(which I don't what type it is): 010100000054E077E6F8F33640FD87F4DBD7AD4340 to EPSG:900913. I have the points which are in the above format ...
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3answers
199 views

Geodesic measurements for short distances throughout US?

My ArcGIS experience has been limited to working on large-scale maps with planar projections. I'm moving to a project in which I want to calculate the distance between pro sports facilities throughout ...
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2answers
57 views

Mercator vs. Web Mercator for Large Scale Topographic Maps

I have 8 terabytes of imagery that is in either lon/lat or UTM projection that I will be using for the basis of large scale topographic maps. I have been studying the differences between Mercator and ...
3
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1answer
244 views

1944 Cyprus Grid coordinate data projection problem in MapInfo

I have coordinate data from the 1944 British Army General Staff, Geographical Section (GSGS) Cyprus map which was cast on the Cassini projection, but was referenced to the Clarke 1880 ellipsoid where ...
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2answers
113 views

How to store lat/long in PostGIS database? [duplicate]

I have a bunch of points in a text file that are represented using lat long (116.3158516 39.9748016). I import them into my GIS enabled database and create trajectories using st_makeline() as ...
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277 views

How to manually change from GPS (WGS84) to web based maps projection systems?

I have collected location point data and wish to display this on a web based map. It was collected using a Garmin Etrex GPS using the WGS84 datum. I wish to display the points using Ushahidi and have ...
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156 views

How do ESRI and QGIS calculate scale values of geographic projections? [closed]

Does anyone know how (from which location) scale values are calculated in ESRI products and QGIS for geographic projections? The only thing I've noticed is that QGIS is changing scales when you pan ...
3
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2answers
172 views

Reprojecting a base map in ArcGIS

I am new to ArcGIS. I have the EDN license (Desktop and Server); have setup ArcGIS for Server in our offline environment; have published several base maps (with caches that ESRI provided me on a DVD) ...
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34 views

QGIS CRS correct, but layers appear warped

I am trying to overlay a raster Landsat 8 scene and vector scene boundary. Both are using WGS 84 + UTM48N. However, the vector (orange line) appears offset when overlaid on the raster. I have checked ...
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24 views

reprojecting (unprojecting) in MrSID decode (SDK)

I am using the C++ SDK (version MrSID_DSDK-9.1.0.4045-win32-vc9). I'm trying to read in arbitrary .sid files and extract rectangular sections of them that can be displayed on top of a "web mercator" ...
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9 views

Why my map just grayscale mode after use MRT?

i just follow the step to change .hdf file to geotiff file from this site http://duncanjg.wordpress.com/2012/12/11/loading-modis-ndvi-time-series-into-postgis-raster/#comment-1214 and i use data from ...
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26 views

Can I get Geoserver to return a WMS in gnomonic projection?

I need to be able to pass in the center lat and long. I have tried using the AUTO Namespace for SRS (which works) but this only supports a few projections, the closest being orthographic. I have ...
2
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1answer
56 views

Definitive list of Proj4 supported coordinate systems

I need to determine the minimum set of coordinate systems supported by all tiers of my project's stack. I have a list of EPSG codes supported by Oracle and GeoServer but I'm having trouble finding a ...
2
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3answers
68 views

matching coordinate systems by transforming and projecting

matching coordinate systems of all my data (transforming, projecting) My data uses the GCS_Bessel_1841 coordinate system. Would there be any inaccuracies if i would transform it to DHDN 3-Degree ...
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0answers
27 views

Appropriate reference system for small-scale mapping of the Middle East

I want to create a thematic map of the Middle East that displays certain historic places and regions on a small-scale map (between 1:6.000.0000 and 1:12.000.000). The map has to center the boundary ...
2
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2answers
48 views

Overlaying misaligned DGN file in ArcGIS for Desktop?

I received a DGN file, I believe created in Bentley 8, and there is a bit of a misalignment problem. The dgn, when overlain on a Bing Maps aerial or NAIP image, shows up about 20 m or so off. I'm set ...
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1answer
97 views

OpenLayers 3 drag and drop interaction with custom projection problem

I am trying to add layers by using drag and drop interaction. Here is jsfiddle.http://jsfiddle.net/anuket/umdwzn10/ It almost works, I mean new layer is added, but for Geometry it gives "NaN". Geojson ...
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0answers
81 views

OpenStreetMap with OL3 and EPSG:3301 projection

Trying to add OSM layer to my map, as Tile layer or as WMS layer, but for Tile layer it is appearing in different projection, and for WMS layer there are error Resource interpreted as Image but ...
1
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1answer
33 views

Mapnik tiles have latitude distortion, projection issue?

I'm trying to work out a kink in setting up mapnik-node. My geos are in postgis, and I allllmost have them rendering properly, but my GIS experience is lacking so I can't seem to determine why this ...
2
votes
0answers
35 views

Mine Grid to UTM

I have been given spatial data (lidar) that was collected in mine grid feet in ASCII format. I am using arc to process but need to define a projection does anyone know how to do this or any other ...
2
votes
2answers
40 views

Formula for charting a course around the globe, given a location and degree heading?

I'm looking for a formula that takes a long/lat coordinate and a degree heading, (e.g. "I'm standing in San Francisco and I'm facing 45º from north"), and which can draw a line across a map projecting ...
0
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1answer
110 views

Regional Large Scale Map Projection Choice

I am currently designing a geospatial product that will be primarily used for large and intermediate scales that cover an entire state of the US or more. The UTM projection would be ideal because of ...
4
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3answers
102 views

Geometric Operations in GIS Systems

I have worked with 2D geometry for CAD - My questions are general and relate to understanding operations on geometric entities (lines). Should geometric operations such as line-line intersection be ...
3
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0answers
49 views

Formula for maximum coverage of a geostationary satellite based on earth station elevation

I am trying to create a javascript function to represent the maximum coverage of a geo satellite for different antenna elevations (0 degrees, 5 and 10 degrees) with 3 leaflet polylines. The result is ...
2
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1answer
37 views

Proj4js: Is this correct implementation of Azimuthal Equidistant relative to an arbitrary center?

If I wanted to interpolate points along a Great Circle Arc, it makes sense that either endpoint of the Great Circle is a satisfactory starting place. Next, I suppose I'll need a projection to preserve ...
1
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1answer
26 views

Transforming Robinson to Equirectangular

I need convert this http://bioval.jrc.ec.europa.eu/products/gam/images/large/access-map.png (is it robinson?) to Equirectangular (ESPG:32662) How can i get this using gdalwarp?
3
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2answers
517 views

Overlaying layers with different projections on Android

Hello, I'm trying to show a map on Android. I'm using two map providers and am having trouble when converting geo point(lat/lon) to point in my viewport(x/y in pixels). 1) the first map provider used ...
4
votes
2answers
87 views

Is there a command line tool for converting projection in .prj and GeoTiff to EPSG codes?

Is there a command line tool to convert a shapefile projection in the .prj file into corresponding EPSG code? I know that there is website http://prj2epsg.org/search for doing this online, but I ...
0
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1answer
325 views

Equivalence of EPSG:3857 for MapInfo 9.5

I have a raster projected on EPSG:3857 with QGIS. I have image registration in Mapinfo but there is no projection for EPSG:3857. Do you know the projection that I need to use?
0
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1answer
60 views

How to create an interrupted Mollweide map in R?

I am wondering if it is possible to create an interrupted Mollweide map in R. This question is similar to Discontinuous or Interrupted map projections? which does not really have a satisfactory ...