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 to I create a .prj file with the following projection parameters?

I have received shape files that are missing .prj files. The documentation for the shape files describes the projection system as Lambert Conformal Conic and provides the following "Projection ...
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How to realize Stereographic projection in openlayers 2?

I have my own tiles and 8 zoom pyramids levels, and now I want to realize stereographic projection by using openlayers 2, is it possible to make it without using other libraries(like proj4js)?
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How to load Tianditu(TileMap) by ArcGIS API for JavaScript 4.0 ? The Projection must be “4490”

How to load Tianditu(TileMap) by ArcGIS API for JavaScript 4.0 ? The Projection must be "4490". The url is"http://map.tianditu.com/map/index.html". Anyone can help me? I need to use the projection(...
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30 views

Reproject coordinates in order to correct them in QGIS

I got two type of coordinates(correct values and incorrects(15m error)), and i want to specify transformation parameters between them in QGIS. I thought that finding Helmert transformation parameter ...
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2answers
760 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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35 views

Converting polyline coordinates to lat/lon for use in google maps

I am given an ArcGIS polyline (or polypoint) from a WFS service (e.g. 1693669.5143, 5672605.5392), and am looking for a function (python, java, whatever) to convert it to a lat/lon so I can use it in ...
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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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219 views

How to get projection data (.prj) of raster image using GDAL/OGR?

I start with a boundary shape-file (think U.S. states) in lat/long that I convert to some projection, and then rasterize the result as a .tif. What I need now are the raster coordinates of the ...
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188 views

Convert to lat-lon coordinates GDAL

I have a netCDF file and would like to convert it to LAT-LON coordinates. 1) I do not know the projection in the file but from the website of the data provider, the data is on a polar-stereographic (...
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19 views

how to project modis blue marble image?

I have combined MODIS blue marble images into a mosaic, a screen shot of the mosaic raster image with its source info opened in arcmap is attached. The file source shows that it has angular ...
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50 views

Open Source Webmaps and Geotiffs

I have recently started to learn how to use open source web maps, and have come across the following issue. When using geoserver and geo explorer (part of the open-geo-suite), I seem to get an ...
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22 views

Are degree based length/area measures comparable across regions?

I have global shp files of basins (polygons) and rivers (lines). I wish to calculate a measure of stream length per basin area. It should be comparable across world regions, e.g. I wish to compare ...
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14 views

Extract lat long point values from EASE2 without reprojection

I have the following file: EASE2 and want to extract the values for this geographic location (148.1, -35.6) #lon lat. How can I do this without the need for reprojecting the ease grid file into ...
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1answer
87 views

Visualizing netCDF file with unknown projection

I'm having a tough time visualizing a netCDF file with poor metadata in ArcMap, which is probably not a surprise. I know the file to contain ozone concentrations over the United States. If I try to ...
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798 views

High Resolution Sinusoidal Interrupted Projection of the Earth

My grandfather built a rather large globe 10 years ago and never got to complete it (he started drawing about a fifth of it by hand and just gave up after that). I have been looking for a sinusoidal ...
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1answer
35 views

Road snapping in R - snapPointsToLine / Projection Problem

1. Introduction (you may skip this if you like) In order to implement a road snapping feature in R for recorded positioning data, I first searched the internet for possible solutions to the problem: ...
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20 views

Appropriate projection for US distances?

I am generating distances between crash sites (points) and urban areas (shapes) and am wondering what the best projection is to use for this task. The area of interest is limited to the U.S. (Alaska ...
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1answer
40 views

How can the gridlines in QGIS be set to be curved lines (neat circles) around polar region (azimuthal projection)?

I am trying to present a map of our polar regions using QGIS software. I am using an azimuthal (polar) projection. I have added a graticule (gridlines) to the map as a background, which are at 10 ...
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Choosing map projections specifically for San Francisco Bay Area?

I am asking because I am not familiar with specific map projections for the San Francisco Bay Area.
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2answers
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Tiled raster image to be placed in an OSM/ Leaflet.js map

I have a mapoverlay in a custom projection which I need to add as a layer to an Openstreet map within a website. Since I was not able to change the projection earlier, I decided to manipulate the ...
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479 views

Identifying coordinate system of San Francisco data?

I just found a dataset of trees in San Francisco, but I'm unable to determine the system used for the coordinates. Here are some samples: 5998894.045593,2119007.035323 6018697.2048701001,2097076....
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Displaying a map in EPSG:26915 projection in open layers 3

My GIS experience is limited to having worked on several Geospatial Humanities projects. That is to say that I still struggle significantly with the technology (and terminology) in getting to my goal. ...
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1answer
33 views

Clipping layer when using new projection in QGIS?

I'm having trouble clipping a shapefile in QGIS so I'll take you through my steps. I've downloaded the land shapefile here http://www.naturalearthdata.com/downloads/10m-physical-vectors/ When I load ...
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1answer
838 views

How can I project geojson borders on the google earth tiles in leaflet?

I started working with leaflet and google earth tiles. I want to add borders on my map so I tried to use the countries geoJson Data as a layer on the map. The problem is that the json borders ...
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15 views

Calculating distances of lines in R

I drew some lines in a GIS application in this projection: +proj=longlat+ellps=WGS84 +datum=WGS84 - is there a name for this projection? I imported my lines into R and to prepare for calculating ...
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31 views

Transform Lat/Lon to LCC and vice versa

I need to convert lat/lon to meters as the unit of measurement to do some calculations. I found this online tool to transform my data from GEO_WGS84_Lat-Lon to LAMGe (LCC). This works for me but I ...
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3answers
390 views

Displaying X, Y coordinates on ArcGIS not working

I am trying to geocode some coordinates I have from my Excel sheet onto ArcGIS but everytime I do so, it doesn't show up on the screen. When I right click on the sheet layer to see where it went, it ...
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Is there a standard for the specification of .prj files?

We use shape files for data exchange. I've looked at the .prj files: different programs produce different prj files. Is there a standard how the parameters must be specified in a prj file? AFAIK the ...
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28 views

Problem with MGI CRS on the Balkan

I have problem with CRS Bosnia and Herzegovina? MGI 1901 / Balkans zone 6 EPSG:3908 MGI 31276 / Balkans zone 6 EPSG:31276 Which of these two is OK? When I open google sattelite image with ...
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453 views

Get Radius in epsg 4326 with Openlayers 3

What is the best method for getting the radius of a circle in Openlayers 3 in epsg 4326 (geodesic)? I'm using this example for a base and trying to draw a circle while getting the radius, but using ...
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53 views

Plot x,y coordinates on a Polyconic Map Projection

I have an image of a large polyconic map projection: (Note that the actual image is much larger, I just made it smaller to upload it.) I would like to take in a user's GPS coordinates and plot where ...
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26 views

Unable to display Gauss Krüger- points

I have this list of sampling points and they told me to display them in ArcMap 10.3.1. This are Gauss Krüger coordinates of soil samples in Austria: From a table I use ->"Display XY data" and the ...
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1answer
658 views

OpenLayers and custom Proj4 Projection

I am trying to map some planetary data on my webMap server using OpenLayers. I defined a proj4 projection as follow: Proj4js.defs["MYDATUM"] = "+proj=longlat +a=1740000 +b=1740000 +units=m +no_defs"; ...
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Working with intersecting polar grids

I'm having some trouble figuring out the best way handle some GIS data. I want to analyze pollution from specific sites at specific points. I have a list of sites I'm interested in all across the ...
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1answer
39 views

Creating an Interrupted Map With OGR, Mapnik and PIL

I am trying to create a simple interrupted Sinusoidal map with Python using OGR, Mapnik and PIL. The general idea is: Make 6x 60 degree sinusoidal maps For each one, make a mask to make it gore ...
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1answer
41 views

Dymaxion/Butterfly alternative projection for QGIS

I've been reading the Dymaxion and Butterfly projections are not open source, so can not be used with QGIS. Are there alternatives to these available in QGIS? I'm looking for a single projection so ...
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3answers
53 views

South-up projection/setting in QGIS

Is there a south-up setting for a projection in QGIS?
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84 views

Explaining scale decrease inside parallels and outside increase for Lambert conformal conic projection?

For a Lambert conformal conic projection, when projecting the cone on the globe, two parallels are formed and the scale decreases between the two parallels and increases outside them. Why does this ...
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Improving Trimble GPS Pathfinder Office and TerraSync coordinate systems workflow?

We have GPS survey projects all over the country (CONUS and OCONUS) and I am wondering what the best practice is for having to deal with multiple coordinate systems. I can go from WGS84 UTM 18N meters ...
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1answer
285 views

Combining UTM zones into one solid map

I have an area, example 4000m x 4000m. So, 4x4km. The origin can be placed anywhere, maybe in center, maybe on the top-left, nevermind. Now, I want to fill this area with some stuff from OSM. I read ...
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1answer
397 views

ScaleLine shows NaN for LCC projection

I have used openlayers along with geoserver. My Map is having LCC projection by default, but SRS is EPSG:4042. The problem is that the scaleline shows NaN in meter as well as feet. How can I correct ...
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2answers
142 views

What's the accuracy of Web Mercator EPSG:3857?

Are there any references on the accuracy or (min/max/avg) error of Web Mercator when it comes to e.g. distance calculations? For the sake of completeness, I haven't found any reference to the ...
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1answer
30 views

Gall-Peters or other cylindric equal-area projections in QGIS?

Is it possible to use Gall-Peters or other cylindric equal-area projections like Hobo–Dyer in QGIS?
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46 views

Openlayer3: projection to Map.view coordinate system

I have an ol.layer.Tile with ol.source.BingMaps in epsg:3857 and I want add it to my ol.Map with projection 4258. The code below does that but when I display the layer it is rendered in the original ...
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278 views

Help, I have 10,000+ .shp files covering 3 UTM zones with unknown projections

I was handed a ton of property files with no projections attached but was told they are all in UTM zone 21S. Well once I merged them all together and projected them I realized that the data covers 3 ...
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25 views

Difference between MODIS sinusoidal and integerized sinusoidal grid

What are the differences between the MODIS sinusoidal and MODIS integerized sinusoidal grid? The sinusoidal grid seems to be currently used, whereas the integerized sinusoidal grid is marked obsolete (...
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Projection conversion issues; Philippines to OSM

I am working with some roads and bus routes data in Philippines. The bus routes data is in Philippines Zone 4: ESPG 3124 projection. I am trying to match it to roads data to generate stops at ...
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1answer
7k views

How to measure areas of features in OpenLayers plugin background maps correctly?

I can't figure out how to make areal calculations (eg. in km2). I have tried the 'field calculator', I have tried the 'measure area' function on the "attributes" toolbar, and i have tried fTools in ...
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2answers
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Mistake in Calculating Area or a Bug in QGIS? [duplicate]

I am trying to calculate the area of a polygon following the step by step mentioned in all the questions related to this issues in this website. Nonetheless, the result of the area calculation is ...