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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Projection for polygon intersection confined into one hemisphere?

I have polygons where each vertex is a (lon,lat) geographic coordinate. I want to find out if they intersect or contain each other. The polygons are guaranteed to never exceed a hemisphere (so they'll ...
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1answer
46 views

What's the correct way to reproject a population raster?

I'm working with a population raster that is in the WGS84 coordinate system, and I want to get it into a projected coordinate system (Albers Equal Area), using ArcGIS 10.1. According to the metadata, ...
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1answer
118 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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10 views

Geodjango transform introduces large errors

Apologies for the possibly naive question. I'm trying to understand how Geodjango (running on PostGIS) deals with coordinate transformations, and am experiencing some unusual behaviour. Let's say I ...
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1answer
14 views

Geoserver projection recognize problem

I'm publishing shape files in geoserver through curl,my problem is that geoserver didn't recognizing the projection which is in ESRI WKT format(layer was publishing).I searched for this problem i ...
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0answers
24 views

Fixing Mapinfo export to Google Earth projection which is slightly off?

I have around 20 layers of data (points and polylines) in Mapinfo TAB files which I need to export to KML files, however the projection is slightly out. I have tried various different projection ...
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3answers
44 views

Problem with Geometry SRID in PostGIS

i ceated my table (borne) in PostGIS id_borne serial NOT NULL, num_borne character varying, shape_borne geometry and i changed the SRID of my table with succes using select ...
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0answers
39 views

QGIS to solve projection mystery in Postgresql

I downloaded some data from local agency. Per QGIS 2.2, I defined the projection to 'EPSG:3587 - NAD83(NSRS2007) / Michigan Central' in postgresql (maybe ArcMap). Data is in Postgresql 9.3. I am ...
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8answers
15k views

How do I convert State Plane coordinates to latitude-longitude?

Given a specific state plane coordinate system (whether NAD27 or NAD83), are there any resources to convert to latitude-longitude?
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1answer
214 views

Is there a standard projection for Sub-Saharan Africa?

With the help of d3.js, TopoJSON, and data from Glottolog I have made this map of Bantu languages that exist in Sub-Saharan Africa. I've used the standard Mercator projection so far. I know that ...
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1answer
149 views

Mercator bias plot in Leaflet

I was inspired by this wikipedia image from the mercator projections page to hack around with leaflet. The idea was to interactively have your cursor move a continent and that it would be corrected ...
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1answer
41 views

Accurate local map projections

Is there a map projection that can accurately represent reality at a local area, i.e. when transforming the map could I choose an area that I care about accuracy and allow distortions elsewhere? Like ...
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2answers
29 views

OpenStreetMap Tile Server with Custom Projection Systems

I am trying to install the OSM tile server on a local machine with a custom projection system like epsg:3573. For the server installation I followed this tutorial ...
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0answers
30 views

MySQL+GDal+MapServer+OpenLayers WebMercator problem

I have a problem/question what is the most efficiant way to go from WGS84 (epsg:4326) to webmercator. Outline of the structure right now: MySQL Database: with point Latitude/Lontiude Data [~200 ...
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1answer
32 views

Correcting coordinates of CAD drawing imported into ArcGIS?

I am having some issues with some CAD drawings that I have imported to ArcGIS. I have a number of CAD drawings where by the features within the drawing have an error in their coordinates. For example, ...
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1answer
304 views

How to re-project the EASE (Equal Area Scalable Earth) grid with a ~25 km cylindrical projection to WGS84 0.25 degree?

I have nc files ,here is one file https://echange-fichiers.inra.fr/get?k=LUfqiyO1Dl7az5bihnS. from the metadata ,the projection is cylindrical and the resolution is 25 km: ...
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2answers
38 views

Choosing projection to use for Least-Cost Path analysis at continental scale?

I am trying to find least cost paths from the southern USA to the Great Lakes region (for example). My resistance layers are currently in an equal area projection but I'm wondering if I should convert ...
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2answers
380 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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1answer
396 views

Determining Natural Origin for a GeoTIFF file (Lambert Conic)

I am trying to display an existing GeoTIFF file (from the FAA WAC set) in an application that requires the GeoTIFF NaturalOriginLongitude tag (FalconView 5.1.1). There are some older files in that set ...
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2answers
180 views

QGIS DXF file projection match

I need to use this file on a map but I am not able to match the projection with the others I have, primarily data downloaded from OSM (city of Boston). I read many articles, I have repeatedly tried to ...
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2answers
336 views

GDAL/proj4 equirectangular projection coordinate system units assumed by OGRSpatialReference and GDALDataset::GetGeoTransform()?

How do I configure my OGRSpatialReference object to specify an equirectangular projection system http://en.wikipedia.org/wiki/Equirectangular_projection where the affine geo-transform matrix (provided ...
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1answer
165 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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0answers
23 views

Conversion problem of projection of MODIS LAI from sinusoidal to geographic

I am trying to change MODIS data's (LAI) sinusoidal projection to geographic. Actually I did it. But when I reproject it by ERDAS, the output LAI raster moved about 10 km to west side of actual shape ...
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0answers
22 views

EPSG1612 transformation [closed]

I have survey data for contacts listed as eastings and northings - I need to overlay this onto PNG files but the location is quite far north - How do I apply EPSG 1612 transformation to the UTM Zone ...
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11answers
8k views

Identifying Coordinate System of Shapefile when Unknown?

I have a Shapefile but its coordinate system is Unknown, and there is no *.prj file. How I can identify it now? Are there any tools that could help?
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1answer
98 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 ...
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1answer
17 views

Projections when using google maps and rest service on openlayers

I am trying to use a rest service on an openlayers map that has 2 google maps layers. The google map layer is set to it's own custom projection (which I had to code into the library by hand, but I ...
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1answer
44 views

projection conversion from mercator to google maps format

Is this spTransform(Finland3, CRS("+proj=longlat +ellps=WGS84 +no_defs+ellps=WGS84 +towgs84=0,0,0 ")) the right way to project a shapefile with this projection coord. ref. : +proj=merc +lon_0=0 ...
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0answers
28 views

Creating a custom Lambert Conformal Conic projection in ArcGIS 10.1 and/or 10.2.2

referring to the table below, I am trying to use the values on the left from another program that uses different terms for the parameters of a custom projection. I just wanted to make sure that ...
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1answer
103 views

Trying to set NAD 1983 EPSG 102631 in QGIS

I was able to find the right coordinate system online NAD 1983 Alaska But now I don't know what to do. I can't find the coordinate system on QGIS. When I choose the one I think is correct it warps ...
2
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3answers
101 views

How to use PROJ4 to reproject a file

Unfortunately, GDAL does not support a particular projection I am trying to achieve (the ob_tran rotated pole projection), so I am trying to use PROJ4 to convert a geotiff file to the projection I ...
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2answers
45 views

How to set a coordinate transformation GRID

Does anyone know how to set a coordinate transformation in qgis so I can measure the distances in meters or kilometers? If anyone has a clue, would be just great. Thanks!
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1answer
196 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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1answer
50 views

Coordinate System Alignment

I have four shapefiles with different original projections that I am trying to bring into ArcMap 10.2. How do I set these four shapefiles to a single projection that will display the layers correctly? ...
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1answer
32 views

WFS request with CQL_Filter projection

I have a layer in Geoserver called bln_blocks. The layer is in EPSG:3857. I am doing the follwoing WFS request with a CQL Filter: var geoserverURL = geoserverURL + '/ows?'; var service = ...
2
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2answers
294 views

How do I reproject one raster to match another's in GRASS

I have two raster layers, A and B, which have information about the same location but have different projections and datums. How can I reproject layer A to match the projection and datum of layer B? ...
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1answer
43 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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1answer
45 views

How to calculate point from lat/long, angle, and distance? [duplicate]

I am trying to calculate the point from a given lat/long, a bearing, and a distance. This is for plotting weather given a aeronautical way point. For example: Given a waypoint with a known ...
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1answer
47 views

problem in scale of projected raster

I have a shapefile (my basin limit) and one raster file that I projected it to the shapefile coordinate system and set its cell size to 1000m(area=1Km2). my basin area is 5400 Km2 and it should ...
0
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1answer
445 views

Coordinate conversion - Lat Long to State Plane, ArcServer-Silverlight

I am trying to project a Lat/Long value I get from a table to a x/y value that I can use to plot a graphic. I have seen one way to do this may be to use something like this: feature.Geometry = ...
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0answers
33 views

projections Basemap and pyproj

I am struggling to understand the projections using pyproj. for now my question is to understand the results of projection operations I have following coordinates that I project on x,y lon = ...
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1answer
81 views

gdal2tiles generates small picture inside 256x256 tile

I've used gdal2tiles for generating tiles in number of different polar projections and always experienced the same problem — strange small picture inside normal 256x256 png with the rest of space ...
3
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2answers
151 views

Selecting features to project to different coordinate system?

I've got data from all over Europe in one feature class projected in Web Mercator Auxiliary Sphere. Due to the fact, that length and area values are not usable I'm now working on a python script ...
2
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1answer
20 views

Applying distance/area dependent procedures in geographic coordinates over large areas?

I'm currently doing some niche modelling with data in geographic coordinates spanning all of Latin America. I am using R for my analysis. Some of the tasks I have to perform are area/distance ...
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2answers
379 views

How to display WGS 1984 Web Mercator (Auxiliary Sphere) services in Google Earth?

The basemap services provided by Esri (on ArcGIS Online, Data and Maps for Sever, and the Data Appliance for ArcGIS) use the WGS 1984 Web Mercator (Auxiliary Sphere) spatial reference (WKIDs 102100 or ...
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1answer
28 views

Can I edit coordinates within an edit session and reproject without reloading the data

I have one lat/long to correct. I edited within my table, saved edits, and now when I project using the Project tool the point stays on my map in the same position. Do I need to reload my data from ...
2
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1answer
24 views

Classic United Kingdom Projection?

When you visit a classroom in the United States and see a map of the contiguous states on the wall, it's usually in NAD83 Albers Equal Area with the central meridian right at 96 West. Is there an ...
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1answer
22 views

Project one layer in qgis using projection CRS of another layer

I am using QGIS 1.6 and have imported a set of latitude, longitude points from a csv file as a layer. I also have another layer from a shape file. When I go to layer->properties for the second layer I ...
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2answers
43 views

Adding a custom projection to the epsg.properties

I have created an entry at www.spatialreference.org of a customized .prj file. http://www.spatialreference.org/ref/sr-org/7973/ I'm trying to add the generated geoserver entry to the EPSG.Properties ...
2
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1answer
314 views

OpenLayers and custom Proj4 Projection

ok so I'm a newbee in using OpenLayers. I try to map some planetary data on my webMap server using OpenLayers. I defined a proj4 projection as follow: Proj4js.defs["MYDATUM"] = "+proj=longlat ...