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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1answer
229 views

Mercator Didn't work on Geoserver

Got some problem with Mercator in Geoserver, I tried to display Flight Information Region that has been stored in my Postgre. The result is more likely drawing using Cartesian projection: I tried ...
1
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0answers
1k views

How to project geographic coordinates (lat/long) to a cartesian system (albers equal-area)?

I am using this matlab package http://www2.ocgy.ubc.ca/~rich/map.html#examples to project the latitudes,longitudes of my data to a specific projection. For this particular case I am using albers ...
2
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1answer
730 views

Defining datum for Lambert Azimuthal Equal Area and converting to geographic coordinates

I posted this question to a specialised mailing list for spatial data analysis using R here but didn't recieve a response. I am working with shapefiles and rasters in R, and I am unsure if I am ...
3
votes
1answer
199 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 ...
5
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1answer
506 views

Custom Geographic Transformation on QGIS

Is there a way to create a custom geographic transformation with specifics parameters in QGIS like in ArcGIS? Okay, I want to tranform SAD69 system into WGS84. Well, I'm in doubt because in ArcGIS ...
2
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1answer
91 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. ...
4
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2answers
5k views

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 ...
6
votes
1answer
364 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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3answers
592 views

PRJ file for Stereo70 S-42 projection

I receive lots of Romanian maps with the projection STEREO70 with Datum "S-42 for ROMANIA". I have only found the "Stereo 1970.prj" by ESRI, and when I open the maps with my GIS software the ...
1
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0answers
111 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 ...
4
votes
3answers
1k views

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 ...
4
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2answers
388 views

Why isn't valid geometry not valid in NetTopologySuite when close to poles?

I have a Polygon which crosses the south pole: Polygon in WKT: POLYGON((5.86826073458095 75.6638564054071,-16.5436836399021 63.2220742891438,-19.3664667294083 59.846221066959,-21.7009816876343 ...
1
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1answer
231 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 ...
4
votes
1answer
148 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. ...
23
votes
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 ...
1
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0answers
250 views

A WMS layer fails to show at some scales

I am tring to overlay my WMS layer on Google but at a particular scale it doesn't show the data of my layer. What can be the problem? <html xmlns="http://www.w3.org/1999/xhtml"> <head ...
6
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2answers
258 views

Projections appropriate for global analysis that preserve area and that preserve distance (but not necessarily in the same projection)

I am looking for a projection (or a set of projections) that decently preserve distances so that I can buffer every country in the world and have a similar level of minimal distortion for each. I ...
4
votes
1answer
836 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 ...
2
votes
1answer
372 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 ...
1
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1answer
172 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
votes
3answers
242 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. ...
3
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2answers
351 views

Is NAD 83 the same as EPSG:4326?

I'm getting mixed messages about these projections. For example -Is this projection below, NAD 83, 4326? GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983", ...
3
votes
1answer
204 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 ...
1
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1answer
432 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: ...
2
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0answers
35 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
votes
2answers
373 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 ...
0
votes
1answer
1k views

Conversion from N,E to Lat/Long And Lat/Long to N,E will always be same? [closed]

I have an excel tool for the conversion of following lat/long: Lat: 23° 11’ 24.67503’’ S Long: 118° 46’ 6.15742’’ E , which gives me following N,E: Northing: 7,434,317.43 Easting: 680,991.69 But I ...
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0answers
173 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 ...
4
votes
1answer
584 views

Openlayers and Geoserver fail to reproject while editing Vector with WFS-T

I can't get the Openlayers and Geoserver work with WFS-T editing a vector layer. I have a layer of points where the Native SRS is EPSG:32639. After trying a lot of combinations, I ended up with two ...
2
votes
1answer
178 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 ...
0
votes
2answers
171 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 ...
2
votes
1answer
444 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 ...
1
vote
1answer
127 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 ...
1
vote
1answer
959 views

Generating Map Tiles for MGRS Grid Graticule

I'm possibly a bit out of my league here, but ready to get my hands dirty. I want to generate map tiles for a MGRS grid graticule similar to http://tiles.mapbox.com/mapbox/map/afghanistan-mgrs. I ...
4
votes
1answer
1k 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", ...
2
votes
1answer
784 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). ...
2
votes
3answers
266 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?
2
votes
3answers
360 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 ...
1
vote
2answers
330 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 ...
1
vote
2answers
479 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 ...
2
votes
2answers
533 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 ...
1
vote
0answers
318 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 & ...
1
vote
1answer
544 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 ...
3
votes
2answers
2k views

How to calculate how long an arc second is for a given long/lat?

The title says it all, really. I am wondering what area is covered by a dataset which is one arc second wide. Thanks, Rob
2
votes
1answer
2k 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
votes
2answers
951 views

Display two layers with OpenLayers at once

How can i display two layers with diferent projections at once? For example i have layer with EPSG:70076 and OSM layer.
4
votes
3answers
769 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): ...
3
votes
2answers
265 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 ...
5
votes
3answers
1k views

Using arcpy what is the most efficient way of projecting a selection from a large data set?

I have a large data set X(x1-xn) from which I must select consecutively the attributes A(a1-an) from X.fieldsSRC or X.fieldDST and project the selections. I have a functioning arcpy script that does ...
2
votes
1answer
135 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.