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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582 views

Help me convert this US Lambert Conformal Conic Google Maps Projection to Australia

Following on from this question: Identify what projection this Australian map uses? <- this is the sort of map i want to load in I need help changing the bits necessary in this example of Lambert ...
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2k views

How do I change from lat/long to a metric coordinate system in GRASS?

Yes, it's yet another transformation question. I am working with ASTER DEM data, which is LatLong WGS84. I want to process the DEM map into an STL file for use in a CFD simulation. The script I am ...
6
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2answers
960 views

Identify what projection this Australian map uses?

Im looking to put this map into google maps as custom tiles, but i now learn what projection is and that this map does not use the same format as google's default. You can create custom projections i ...
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0answers
176 views

Sort a collection of points based on proximity using pythagorean (2D) distance

I would like to present a user with a list of points, sorted by proximity to the user's location. Is there any problem with using the pythagorean formula to calculate the two dimensional distance ...
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1answer
882 views

How to get spatial reference of a shapefile using python?

I always use arcpy.GetParameterAsText to get the spatial reference from the user. There should be a way to decide what is the spatial reference of a shapefile but I can't find it. Something like ...
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1answer
1k views

How do I project a Azimuthal Equidistant global map into a circle in QGIS?

I'm fairly new to QGIS/GIS stuff in general, so I apologize if this is too simple of a question, and I'm just bad at finding my answer. I have a shapefile of all the countries in the globe I ...
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2answers
2k views

What is the standard Mercator projection?

I'm using QGIS in order to re-project a shapefile I have into "Mercator" so that something like protoviz understands my co-ordinates. Protoviz tells me "Mercator" ...
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1answer
765 views

How to make SVG Stabius-Werner projection

I'd like to create a SVG file of a Stabius-Werner projection of the Earth. The image in the linked page is nice in that it's very high resolution (2,058 x 2,065 pixels), but I'd like to see if I can ...
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1answer
100 views

Images displaced in UTM

I recently received a collection of satellite images (GeoTiffs) and their indice. Originally, the indice came in a geographic projection (GCS WGS 1984) and the Geotiffs projected to the appropriate ...
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0answers
961 views

How do I redefine the projection of a DEM?

I have a DEM that was exported from AutoCAD civil 3D 2013 but it's in the wrong projection. I'm using an area specific projection that was not provided as an option in CAD DEM export dialog box. I ...
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2answers
732 views

Is it possible to reproject KML using ESRI's Javascript API?

Specifically into NAD83. Google tells me that KML only supports WGS84, but I can't seem to find much info on being able to reproject KML using ESRI's Javascript API. Basically, I've got this base ...
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1answer
223 views

is it possible to project a shapefile to a raster's custom projection with command line gdal/ogr?

I have a raster with a user defined sinusoidal projection and a shapefile in lat/lng coordinates (I believe this is called 'unprojected'?). I'd like to use ogr/gdal's command line utilities to ...
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98 views

Van der Grinten IV projection. Is it possible and how?

I like the look of the Van der Grinten IV projection with it's two hemispheres and would like to use if for a map of the world. I could only find information on how to use the Van der Grinten I ...
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1answer
555 views

GIS - Coordinates / Projections, Google Maps

I'm currently working with OS data and have just tried to import a table of google maps coordinates/point data into ARC. The data frame (& layer) coordinate system is as follows: ...
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2answers
462 views

How to use OpenLayers OSM-Layer with degrees instead of meters?

I have an OSM-Layer as a base layer. When I create a vector I have to define the coordinates in meter. Is there a way to use degrees right a way without reprojecting them beforehand to meters? var p0 ...
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2answers
1k views

How to create an Azimuthal Equidistant map for long-distance radio?

I'm trying to produce world or continent scale maps that use the Azimuthal Equidistant projection. I'm a radio amateur, and to an antenna, the whole world looks like spread out on a flat plane, with ...
6
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2answers
877 views

Is it possible to use the Goode Homolosine projection in QGIS?

Is it possible to use the Goode Homolosine projection in QGIS? Both QGIS and GRASS seem to have trouble with the interruptions, squashing the higher latitudes together. I tried +proj=goode ...
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4answers
954 views

Which UTM system do you recommend for Tamaulipas, Mexico?

I'm working with QGIS 1.8.0. Could anyone tell me which UTM system would be better to project a map of Mexico? There are too many to choose from. I have to convert my maps from WGS84 to UTM to do some ...
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1answer
1k views

Changing the CRS of a shapefile

Im trying to convert shapefile from one CRS to another in QGIS. On the layer menu, I right click on the shapefile, save it as with other name and there I change the CRS to the desired one (WGS 84). ...
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2answers
188 views

Projection 27700 in the OpenGeo Suite SDK GXP

I have some data stored as UK grid references, they display just slightly off alignment on the map after I followed the OpenGEo EXP tutorial using these settings (below) however when I change the EPSG ...
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1answer
33 views

Network segment gaps, when offset

I'm having an issue when offsetting a line shapefile. For some reason when the lines are offset, ArcGIS isn't drawing some segments although the segments are there confirmed via “identify”. Has ...
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1answer
91 views

Why isn't enabling on the fly projection reflected in raster? QGIS 1.8.0

I have imported a map from the Ordnance Survey Open Data website. It is a 50k Street View raster. I have also created a new shapefile layer in which I have created a polygon overlay for the raster ...
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1answer
285 views

What SRID is this projection?

Anyone know what the SRID is for the following projected coordinate reference system: { PROJCS [ "Florida 0901, Eastern Zone [1983, US Survey feet]", GEOGCS [ "NAD 83 ...
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1answer
188 views

Albers Conic versus State Plane Zone in terms of accuracy

I'm trying to determine if an Albers Conic (Alaska Albers) is suitable as a projection for a corridor 800 miles long by 50 miles wide, that goes from the north coast of Alaska to the south coast. ...
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3answers
2k views

What is a good projection for the whole of China (with units in meters)?

I get some GPS results which lay in China with WGS84 coordinate system, and I need to choose a projection to reproject for. First I chooses the UTM projection, but I find the results lay in ...
3
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1answer
2k views

Setting coordinate system in PostGIS

The geographical information data that INEGI (part of the Mexico's goverment) provides are in the following coordinate system (or is projection?) Lambert Conformal Conic, double standard parallel ...
2
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1answer
134 views

Using ogrinfo to list all projection source of a database [closed]

I have to reproject all the layers from a database, but some of them are undefined and some are defined in a wrong projection. I would like to sort all those layers in a text file with their source ...
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1answer
341 views

Working with Interrupted Goode Homolosine data

I'm trying to use Global Land Cover Characterization data from the USGS: http://edc2.usgs.gov/glcc/fao/data_specifications.php It is in the Interrupted Goode Homolosine projection. As I am working ...
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0answers
30 views

How to quantify projection distortion using ArcGIS [duplicate]

I am trying to figure out a workflow to quantify the amount of distortion for different projections throughout a given area of interest. I am thinking in the form that you would do a relative ...
2
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0answers
224 views

Mercator projection that shrinks toward pole

I've noticed that lots of map viewer (especially those nautical chart viewer) will shrink a mercator projected chart while panning towards poles. Is this some compensation for mercator distortion? ...
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1answer
368 views

Openlayers and KML layer projection issue

I'm not a GIS expert at all, but I've been asked to add a KML layer to an Openlayers map which probably needs some tweaks and that's where I get confused. Let say I have an Openlayers map with the ...
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2answers
8k views

Choosing the correct value for proj4string for shape file reading in R “MapTools”

I am having a shape file of polygons and another CSV file which contains a list of points as (Lat, Lng) pairs.. I want to check for each (lat, lng) pair from the CSV file which polygon does it fall ...
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1answer
923 views

EPSG:4326, EPSG:3857, JOSM and unprojections

It is said here that EPSG:4326 is not a projection. In my mind, a projection is a transformation of the surface of the Earth producing a flat image, notably a bitmap. We know that WGS84 (World ...
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1answer
1k views

How to make polygon shapefile containing WGS 84 UTM zones as features?

I need a shapefile with polygon features. Each feature has to be a unique UTM zone (each zone is 6 degrees) in the northern hemisphere. I have no idea how to make it - Create fishnet gives a wrong ...
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3answers
2k views

Distance measurements across UTM zones: use geographic or planar approaches?

I have a survey grid spread across 3 UTM zones (36N, 36S, 37S). I want to find the nearest (or shortest) distances of the centroids of these grids to roads and various points between. It seems like ...
3
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3answers
3k views

What is the formula for calculating world coordinates for a given LatLng in Google maps?

I want to calculate a given LatLng to the world coordinate . I know I can use the internal projection of Google maps like this: var map=new google.maps.Map(...); ...
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2answers
778 views

Calculation for conversion of Lat/Lon to World Geographic Reference System (GEOREF)

Does any one have a reference to, or the actual code, to convert Lat / Lons to Georef code (http://en.wikipedia.org/wiki/Georef)? I am also interested in finding a conversion from lat/lon to MGRS. ...
2
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2answers
2k views

How can I use GDAL to batch define a projection?

I have a fodler with 1500 ECW rasters, no spatial reference information defined. Can I use GDAL to batch define a projection for all 1500 in the folder?
2
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1answer
197 views

Stumped on python looping and data dictionaries

I have been stumped getting my python code to work for a while now. I've been using python for the last several years on and off for simple things, but I am far from an expert in python. I am trying ...
7
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1answer
495 views

Geometry Projection Speed Test

Lately I've been using the OGR projection classes that come with ogr/gdal, but pyproj was recommended to me, so I thought I'd give it a try. To help me decide if I should make the switch, I did a ...
2
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1answer
76 views

When is a projected length calculated via a pythagorean distance more accurate than an ellipsoidal length?

I'm using spatialite 3.0.1 with the following test data (in EPSG: 4326): Name astext(geometry) ---------- -------------------- Belitsa POINT(23.563 41.947) Malko Tarn POINT(27.533 ...
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0answers
87 views

Why does ERDAS not like my GDAL output?

I am creating a raster using GDAL and the IMAGINE file doesn't work in ERDAS because it doesn't recognize the projection. Here is the code to generate a sample: from osgeo import gdal projectionWkt ...
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1answer
123 views

openlayers:transform from ITM to 900913 is not accurate

i did a custom projection ITM (Israel TM) and i then am doing transform to all the feature before im adding them to the map, from ITM to 900913 proj because i want to show the feature on the map. this ...
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0answers
59 views

CRS centered on the 180 meridian?

The problem I'm dealing with is the old 180 meridian problem, except I'm not trying to plot or render shapes that cross it, I need to do intersections of lines that cross it. The only spherical ...
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0answers
189 views

Changing the projection of the output to my OpenLayers click event handler

I've been playing around with the OpenLayers click event handler example, which you can see here. It tell you the coordinates where you have clicked but I am trying to change this to be in decimal ...
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1answer
410 views

Convert from Mercator to transverse Mercator projection in C++?

I'm writing code to import images from a WMS server into some software. However, the software expects the images to be in transverse Mercator, but the WMS server provides it in Mercator. This ends up ...
2
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1answer
155 views

Wrong object size after projecting spatial data from one coordinate system to another

I am having problems reprojecting items in ArcMap 10.1 from British National Grid To WGS84. (WKID: 27700 Authority: EPSG to WKID: 102100 Authority: ESRI) All Polygon Layers I project [I use Project ...
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2answers
221 views

Measurements across UTM zones, how to apply spatial parameters to a customize a projection?

I have a survey grid that spans 3 UTM zones. Using http://www.epsg-registry.org/ I can get an indication of what projections are available. Where can I find more info on the patterns of distortion ...
0
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1answer
150 views

Openlayers: transfer from custom projection to map projection

I am building webApp with openlayers that contain a map that allowed insert edit and remove points, my map is now using “EPSG:4326" projection. I have shp files and xlsx files that contain polygons ...
3
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1answer
730 views

Projection of Shapefiles for Spain (INE)

I downloaded the official shapefiles for the municipalities of Spain from INE here. It has a lot of shapefiles, but I found out that the right one for what I need is esp_muni_0109.shp. I would like ...