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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55 views

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 ...
4
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1answer
96 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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0answers
32 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
39 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
95 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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8answers
16k 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
228 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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2answers
70 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
88 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
58 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, ...
3
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2answers
254 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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0answers
81 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
25 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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1answer
35 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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0answers
71 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 ...
2
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3answers
158 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
54 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
61 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
91 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 = ...
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1answer
102 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
59 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
664 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
45 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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2answers
155 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
25 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
684 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
32 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
26 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
33 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
88 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 ...
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0answers
53 views

gdal read whole geotif band into vector

i have another c++ GDAL question. I try to read alle elevation data out of an GeoTiff file into a c++ vector so that i can get elevation at x,y like this: vector[x][y]. I also like to use this data to ...
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0answers
30 views

cs2cs works one way but not the other

I am trying to build a short program using cs2cs that will work on any windows pc I copied cs2cs.exe and proj.dll to a seperate folder When i run this to convert israel tranverse mercator to decimal ...
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2answers
389 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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3answers
391 views

C++ coordinate class that automates projection?

Can anyone point me to a C++ class for representing coordinates that automatically handles projection transforms? What I'm thinking of is something that would allow me to create vars that incorporate ...
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1answer
499 views

Projecting Imported NetCDF file correctly?

I have 360 NetCDF files (.nc) that I need to import into ArcGIS. They hold monthly historical climate data in the U.S. When I tried to import one, using the Make NETCDF Raster Layer tool, the ...
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0answers
30 views

Mapnik projection for rectangular coordinates

I am trying to use mapnik to render indoor floorplans and am having a little trouble figuring out the SRS projection. I have geoJSON that represents the floorplan. The coordinates are just cartesian ...
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2answers
224 views

Changing layer extent to decimal degrees?

Using ArcMap or ArcGIS 10 ... In the photo below, you can see my extent is in meters while my projected coordinate system is in decimal degrees. How can I convert my layer extent to decimal degrees? ...
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0answers
40 views

50m x 50m grid around the world

I'd like to subdivide the earth into a grid of approx. 50 x 50 m cells (big database, I know). To make it more complicated (and fun), I also need to be able to determine to which cell a given set of ...
0
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3answers
65 views

Defining custom projection using baseline survey coordinates

I have CAD data that I need to incorporate into a GIS analysis. The CAD data does not have a defined projection, but the drawings include a table of survey baseline points. I need to know if I can ...
2
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2answers
98 views

which map projection should be used for global map with geography and human demographics

I am working on a project to try to identify the most threatened populations (on a global scale) of having a limited access to freshwater. I want to compare those most at risk currently and then add ...
3
votes
1answer
100 views

Is there any Google Maps-like zoomable world map, but with an equal-area projection?

Whenever I look at Google Maps at a global or polar area, the projection hurts. Is there any web service with a zoomable world map, that uses an equal-area projection — preferably pseudorectangular ...
3
votes
1answer
37 views

Why are Google Mercator and UTM rotated towards each other?

Being a self-taught GIS user, I struggled a while before getting the grips on map projections. But now this: because I like to use OpenStreetMap as a background layer for orientation, I have saved my ...
9
votes
3answers
6k views

How does ArcGIS compute the distance between two points with a non-equidistant projection?

This is a follow-up question to my previous one, Can you suggest some well-written introductory texts about coordinate system projections? Let's assume I'm working with the CH1903 map projection, ...
0
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1answer
381 views

How to use Google Maps projection with GeoDjango/PostGIS

I am building a web service with GeoDjango which involves user submitted events including a location. I created a model field for my location using django.contrib.gis.db: location = ...
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1answer
122 views

OpenLayers Plugin with on-thy-fly-transformation causes wrong coordinates

I am using the OpenLayers Plugin with the maps from Google Satellite. In Qgis I have chosen on-the-fly-transformation into WGS 84. But the WGS 84 coordinates in Qgis are now 0.15 degrees further E ...
23
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4answers
2k views

How does one calculate distortion on Equirectangular Projection?

I am trying to calculate distortion so I can distort overlaying text and forms to precisely match an image of an equirectangular projection. So, how does one calculate the distortion at a given ...
0
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1answer
62 views

Copy .prj file into QGIS projection folder

I want a custom projection used in ArcGIS be available in QGIS. I have the .prj file copied out of a ArcGIS folder (containing different projections). Now, I want this file to be added into QGIS. Is ...
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0answers
37 views

Get XY in different projection without changing data frame using python addin [duplicate]

I been searching for a way to use this http://forums.arcgis.com/threads/49273-getting-xy-from-mouse-click-using-python tool but print the XY in different coordinate system like WGS 1984 (decimal ...
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0answers
63 views

km measurement in qgis with EPSG 4326

I'm struggling with a small issue. I'm working with the master version of QGIS and I have some layers loaded in my project. All the layer are in 4326 projection and the on the fly option in NOT ...
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0answers
36 views

Problem with projection in meters with ArcGIS 10.1 [duplicate]

I hope you can help with the following problem. I have a shapefile and want to project it using a projected coordinate system with meters as unit. What I did was to change the projection from ...