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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Why are the tile coordinates different in Google maps and Google earth?

I have a .NET application that typically uses the standard Google Maps JavaScript API V2. Within this application I am using a GTileLayerOverlay to add my own custom dynamic tile layer. function ...
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1answer
99 views

Need software to read geo information from tif

I am trying to verify the lat/lon and ECEF values that I have determined for a very specific and unusual situation (a geotif file), and it would be great if I could find some software to read them. ...
6
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1answer
572 views

Create Mercator map with arbitrary center/orientation?

I want to see a Mercator map where I choose what latitude/longitude is in the center and what direction is "north". In some sense, a Mercator map of a rigid rotation of the globe. Does such a ...
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2answers
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Arcmap 10 feature with undefined coordinate system projects incorrectly when projecton is defined

I'm fairly new to GIS, and am slowly feeling my way through ArcMap 10. I have run across a problem defining the Geographic Coordinate System and projection for a feature (the feature currently has an ...
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0answers
116 views

How to compute a map-to-screen transformation?

Every projection calculation I have come across dealing with the Lambert Conic projection converts the given Lat & Long to meters. So now the magical question: how on earth do you take the meters ...
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Convert an arbitrary meta-data-free map image into QGIS project

My background: experienced programmer, amateur historian, complete beginner to GIS (so I'm using QGIS). I did learn to use the QGIS georeferencer tool though. The input: suppose I have an image like ...
2
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3answers
390 views

coordinate definitions from nyc.gov open data SpatialLocation field

The NYC Open Data website has a dataset of street events. The last column is called SpatialLocation, and is defined as a text field. An example is below. It is clearly two points on a physical map. ...
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1answer
158 views

What is the most appropriate Projection for the Gulf coast region?

What are the most appropriate datum and projection I could use for the Gulf coast region - spanning Louisiana, Mississippi, Alabama, and Florida? I have to analyze block group data along the coast. ...
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1answer
250 views

QGIS Projections

I am new to the GIS world and have faired pretty well with ArcGIS 9.3, learned and still learning on the job. I would like to get a better handle on QGIS though. I linked the files from my dropbox. I ...
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2answers
192 views

How do you pass parameters for Proj4js implementation with OpenLayers

I am using Proj4js along with OpenLayers for the transformation of x,y (projection type is Transverse Mercator) to long, lat. While executing "inverse()" method what I noticed that in tmerc.js some ...
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1answer
143 views

Tool For Generating Formula for Projection

I am using Proj4Js for northing,easting to lat,long transformation. My Datum is "AGD84" and projection is "Transverse Mercator". While doing so I found that if I don't specify "+proj" parameter in ...
4
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1answer
1k views

How to use DotSpatial to project/reproject shapefiles on the fly

I would like to use DotSpatial to reproject shapefiles on the fly before loading them to GeoServer. I've been looking for tutorials on how to get started with this in vain. Any pointers on where I can ...
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1answer
206 views

Looking for CRS for NAD 83 UTM Zone 30N

I'm curious as to why the UTM zones are incomplete for NAD 83 in QGIS? I have a WGS84 shapefile that I would like to project to NAD83 UTM Zone 30N but can't find it in the QGIS CRS list. I see how ...
2
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1answer
438 views

Uploading unprojected shape files using GeoServer REST API

I have a number of shapefiles that lack the .prj file. I'm able to upload them to geoserver using the rest api. However, I'm unable to serve them after upload. Which brings me to the question as to ...
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1answer
248 views

2 Shapefile vectors will not plot properly in same space

There are slight differences in 2 shapefiles projection information. I have activated on-the-fly, but they do not plot in the same space. I tried to save as new shapefiles with the same CRS, but ...
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1answer
491 views

Reprojecting non 4326 WMS image to spherical mercator

In OpenLayers, I'm trying to display a WMS overlay (EPSG:4269) from a server I don't have control over to a spherical mercator projection. Is there an equivalent to this: ...
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0answers
36 views

Why did my shapefile distance get smaller after changing the projection? [duplicate]

Possible Duplicate: Layers having the same coordinate system should overlap, but they don't. What's wrong? I'm working with a shapefile that has a geographic coordinate system and I ...
5
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2answers
430 views

Mass-update the projection in compressed GeoTIFF files

I have a huge set of compressed GeoTIFF files. Someone forgot to set the projection while creating the GeoTIFF files and I would like to add it now. If I use gdalwarp -t_srs source.tif ...
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0answers
200 views

On the usage of Proj4Js->tmerc.js

I am using "proj4js & open layers" for my mapping. I got projection & datum (which is based on "Transverse Mercator") of a local plane and this plane is part of a grid which returns ...
2
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1answer
213 views

How to add FP_WGS_84_IBCAO_Polar_Stereographic projection to QGIS?

I have a GeoTiff image that is projected (see below) I would like to add this projection to the list of CRS in QGIS. Can someone help me do this? Thank you very much in advance!!! Francis ...
2
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1answer
632 views

How to transpose the lat/lon coordinates of a shapefile?

I need X to be Y and Y to be X (switching lat/long) within the polygon shapefile. If it were a point shapefile I know I could simply reverse the lat/long or x/y parameter and import from a table. I'm ...
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2answers
490 views

Error when setting projection of a tif file in QGIS. Any ideas to solve this? [closed]

I get this error when trying to define a projection for a tif file in QGIS: ERROR 1: Too many points (3249 out of 3249) failed to transform, unable to compute output bounds. How do i work this out? ...
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3answers
1k views

Convert Nasa's Blue Marble into a cubic projection

I'm looking for a free tool to convert the cylindrical projection map of the Earth's surface that you can get from Nasa (under the Blue Marble project): ...
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1answer
2k views

Distances in {Plate Carrée projection - EPSG:4326 - WGS84}

So, "4326 is just the EPSG identifier of WGS84" [3], indeed http://spatialreference.org/ref/epsg/4326/html/ says it is a GEOGraphic Coordinate System: GEOGCS["WGS 84", DATUM["WGS_1984", ...
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1answer
1k views

Projection ETRS89 (Ellipsoid: GRS80) 6-Degree Zone 33 to UTM33N - WGS84

Hi I'm having trouble to reproject a shape file in Qgis. The projection is supposed to be "ETRS89 (Ellipsoid: GRS80) 6-Degree Zone 33" and I would like to project it to UTM33N - WGS84 (EPSG 32633). ...
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1answer
328 views

Looking for help identifying projections and reprojecting

Hi there at the new forum, I'm still struggling with projections in qgis. The "Vogelschutzgebiete" reprojection worked. But these ones seem to be tougher: ...
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1answer
4k views

How to change the projection of a UTM-georeferenced raster in Quantum?

I have a project file in Quantum which contains some shapefiles and rasters that are properly georeferenced. However, I have started using GeoTiffs which are in UTM - WGS84 that don't seem to be ...
2
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3answers
334 views

Are there WMS servers providing maps of UTM zones, actually in the zone projection?

There are lots of EPSG:4326 (lat lon) services out there but if one has to use an UTM projected map as base layer to display utm scenes, are there any WMS endpoints publicly available for that?
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2answers
384 views

How to shift the Map a little bit?

I'm having trouble with two maps, both UTM33N/WGS84. They should be exactly on top of each other but there is a slight shift between them of probably a few hundred meters or so. I Tried to adjust ...
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2answers
557 views

Re-initializing OpenLayers Map with different projection

Is it possible to re-initialize OpenLayers Map with a different projection ? Scenario: OL Map with projection 4326 is created, along with click, measurement, drawing handlers. A button to switch to ...
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2answers
648 views

LonLat Points to Grid of Polygons in PostGIS

I'm going to preface this with it's my first time using PostGIS. I'm starting out with a 5 km x 5 km grid cell in which I know the center point lon/lat (SRID=4326). I'm trying to create a polygon for ...
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387 views

Conversion From Transverse Mercator To Longitude & Lattitude

I have to transform (7-parameters datum transformation) coordinates from northings & eastings to lattitude & longitude. Following are details of source coordinate system(i.e. northings & ...
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1answer
592 views

Reprojecting a shape to UTM33

I still have trouble reprojecting shape files :( I would like to reproject it to UTM33N / WGS84 (EPSG 32633) I think the projection of the shape might be Pulkovo 1984/ Gauss-Krüger Zone 4 (EPSG ...
2
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1answer
179 views

Is there an arcpy boolean check for whether an EPSG or prj is supported by arcmap?

I'm writing a tool and essentially I found out that arcmap defaults an epsg to 0 if it sees that the projection is not supported against the predefined projections.
3
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1answer
3k views

How to correctly specify coordinate system?

Using QGIS v. 1.9 (1.7 does not seem to be available for Ubuntu Linux 12.04), do the following: Create new project, specify coordinate system by clicking on button in bottom right hand corner, ...
3
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2answers
391 views

How do you change the prime meridian of a map?

I am working with the Natural Earth world map as a SHP file, but when I try to change the prime meridian (PRIMEM) of the coordinate system ...
3
votes
1answer
842 views

What is wrong with this Proj4 transformation?

I'm implementing support for WMS maps in my company's software. Servers return a list of projections their maps are available in, but our software only displays data in WGS84 (lat/lon or UTM), and ...
2
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1answer
226 views

Automate database conversion from NAD83 to Web Mercator

A NAD83 database is updated daily while a Web Mercator clone is only update when time is available. Looking to automate this process of Copying Layers Projecting them to Web Mercator Placing in ...
4
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2answers
3k views

How do I get the distance meter value between two geometries in PostGIS?

I have a simple question about calculating distances in PostGIS. I would like to get the distance between two geometries. I am using this sid : 4269 in meters what i am doing now is this : ...
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0answers
377 views

How do I use Proj4js or other technique to make custom map projections with google.maps.Projection?

I'm using Google's Projection class to try to convert my map projection from the default spherical mercator to something like Lambert Conformal Conic. I was previously adapting the code from this ...
4
votes
3answers
6k views

How do I include proj4js in openlayers?

in my Openlayers app, since the base map projection is not epsg900913 or 4326, I need to include proj4js in order to use geolocation feature. but i got such a error notice: GET ...
10
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2answers
352 views

How do I determine the projection of a paper map?

If I'm reading a paper map how do I determine what projection was used to draw the map if such information is not explicitly labelled on the document? Online it is easy to find resources (for ...
4
votes
1answer
311 views

Projecting gps data to get length of resulting line shape in ArcMap 10.0

I have gps data in WGS84 geographic coordinates. I will use the gps data to build a line shape in ArcMap 10.0. The data falls in UTM 15N. To get most accurate length of line, should I project the ...
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0answers
149 views

How to show an array of 2d points/polygons in Polymaps (Cartesian coordinate system)

I need to display these 2d points/polygons (Cartesian coordinate system) on Polymaps with GeoJson layer. I do not use the other layers. Do I need to convert xy coordinates to the lat lon? If so, how? ...
2
votes
1answer
3k views

How to convert decimal degrees units to km in R?

I am trying to figure out how I can transform my unit of length from decimal degree to km when I import the following simple ArcGIS polygon shape. Ultimately, I would like to have this information ...
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58 views

What projection is this [duplicate]

Possible Duplicate: QGIS - Hell of time with CRS and vector intersect The tax assessor parcels layer I referred to in my first post gives this as its projection: +proj=lcc ...
3
votes
2answers
1k views

Image tiling math

I've been looking at MapTiler for the logic on how to render an image as tiles on a (google) map. Instead of storing the single tiles locally in a folder structure I want to use Djatoka. I'm able to ...
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0answers
530 views

Geoserver tiles mismatch

I tried to get WMS tiles from geoserver like /geoserver/gwc/service/tms/1.0.0/layername@EPSG%3A4326@png/15/19142/9530.png or with another projection ...
3
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1answer
410 views
2
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101 views

raster data expressed as percent

I downloaded NDVI greeness data from the USGS Integrated Vegetation Mapping Viewer. In the metadata it says that visual greenness values range from 0 to 100. My data is from the period ending 3/5/12 ...