A reference framework consisting of a set of points, lines, and/or surfaces, and a set of rules, used to define the positions of points in space in either two or three dimensions.

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0answers
255 views

how to correct the coordinate of points [closed]

I have some a layer which contains some points. The coordinate of the points should be GPS points. However, the coordinate of these points are not correct. What should I do? I am using QGIS. If I ...
3
votes
1answer
465 views

How to create aux.xml file?

after starting to use MOBAC to create offline background maps I found the aux.xml files very useful as QGIS automatically sets the CRS so this would be very useful for my colleagues with smaller GIS ...
7
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3answers
5k views

Geodetic Coordinates And Latitude, Longitude

Would it right to say that geodetic coordinates (phi & lambda) are the same as latitude & longitude?
1
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1answer
1k 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 ...
1
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1answer
2k views

distanceTo is giving wrong result in OpenLayers?

Hi i am using distanceTo from OpenLayers to calculate the distance between two locations these are map details Geographic = new OpenLayers.Projection("EPSG:4326"); Mercator = new ...
5
votes
1answer
1k views

MGRS in OpenLayers

I am trying to view the Military Grid Reference System coordinates in Openlayers through the MousePosition control. Is there an easy way to accomplish this just through Javascript? I am looking at the ...
2
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2answers
1k views

Convert RT90 into WGS84

Goal: Gain WGS84 decimal to locate some cities in Google Map. Problem: I don't know how to convert the value of the RT90 coordinate system into WGS84 in SQL Server.
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1answer
256 views

Coordinate systems

Does the Coordinate system of a data frame in ArcMap have to match the coordinate system of at least one of the layers in the table of contents? I have found that if defined it will take on the ...
2
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0answers
102 views

When using OpenLayers plugins maps, can I have Longitude/Lattitude labelled on my grid when using the Map composer in QGIS?

Using OpenLayers plugins maps, can I have Longitude/Latitude labelled on my grid when using the Map composer in QGIS?
2
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2answers
684 views

Moving all shapefiles (SHP) in MXD to new File Geodatabase (*. gdb) using ArcGIS Desktop?

What I need to do is to move all the shapefiles in an mxd into a newly created gdb, checking prj, and update mxd reference. I have ArcGIS 10 SP4, license ArcView. I studied a bit of Python and get ...
2
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0answers
120 views

Changing CRS crashes QGIS every time

When I open QGIS, and use the tools, setting -> project properties, QGIS will crash. When I also use the setting -> option -> CRS , Select new CRS also causes a crash. It looks like couldn't use the ...
1
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0answers
322 views

ogr2ogr failed to reproject shapefile error exceeds limits

I cannot get correct transformation from WGS84 to the Hungarian EOV EPSG:23700 (Hungarian Datum 72) using ogr2ogr. I am using ogr2ogr from the fwtools shell. I have a shapefile in GCS WGS84 (epsg ...
3
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2answers
303 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 ...
4
votes
0answers
260 views

Can GeoTools parse GML CRS definitions?

A kind of branching of this question. Soon I will need to handle GML Coordinate Reference Sysyem definitions in a Java servlet. Links: GML OGC reference. Concrete example. I know that GeoTools ...
2
votes
1answer
153 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.
0
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2answers
5k views

How to convert from UTM Zone 36N Mercator to WGS 84 degrees of lat and long?

I have acquired many coordinates from a points I extracted from polygons. The points are in WGS 84 UTM Zone 36N, and I want to use them on Google Maps. I found out that they use different systems (I ...
2
votes
1answer
422 views

coordinates in dbf file wrong

I am new to ArcGis, so please bare with me :D . I converted a polygon in an mdx file I have to a shape file, then converted its vertices to points, then used "add X Y feature" and choosed coordinates ...
1
vote
0answers
279 views

Create IPoint with Lat/Long in decimal degrees and Z in feet

I have written an ArcMap v10 AddIn that reads a folder of geotagged JPEG's and creates a new feature class where each point is the geotag information from on of the JPEG's. The issue is: The GPS ...
4
votes
1answer
410 views

EPSG operations and operation methods

Querying through the EPSG database, I can see the tables epsg_coordoperation where transforms and conversions between different CRS are stored, and epsg_coordoperationmethod which stores the ...
1
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1answer
100 views

Which SRS is computational more effective to store continental scale data? (given some conditions)

For a Precision Agriculture application I need to make calculations in UTM projection. The data will be stored in Postgis and is made of soil samples results (point data) and field boundaries of many ...
20
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1answer
4k views

Is WGS84 itself a Coordinate Reference System?

I was wondering the difference between WGS84 and EPSG:4326 (see this). Can then WGS84 on its own be defined as a Coordinate Reference System? Or is it just a datum so that a Coordinate System must ...
6
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1answer
1k views

Difference between Geographic-3D and Geocentric CRS

I'll start with the OGP definitions: Geographic. A coordinate reference system based on a geodetic datum and using an ellipsoidal (including spherical) model of the Earth. This provides an accurate ...
4
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1answer
495 views

How to define a CRS using a projection rotated about a given point

I have a data set that uses a common projection, but has its own false easting and northing, and is rotated 315 degrees. I need to be able to work in this CRS and easily translate from one CRS to ...
3
votes
1answer
2k views

How to get the coordinate system from a PostGIS database?

My question is probably amazinlgy stupid, but I can't find the answer myself. I would like to extract from a database the latitude and longitude of points. For now, I'm getting x(the_geom) and ...
3
votes
2answers
388 views

How to make QGIS recognize EPSG:31468?

I have Shapefiles without a CRS (e.g. without .prj file). I would like to set the CRS (EPSG:31468) before I pass the Shapefiles. I tried the following: Setting a .prj file manually with the string ...
1
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1answer
95 views

Read height data from Meridian 2

I'm having difficulties reading the Gridded height data (OS Meridian 2). I'm loading with OSGB 1936 reference system but have trouble finding the lat/lon data for each point. i.e.I open the attribute ...
0
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2answers
1k views

How to convert Grid North & Grid East into latitude and longitude?

We have grid north and grid east data that we have received for address information. How can this be converted into latitude and longitude? I am not sure what format this grid_east and grid_north data ...
19
votes
7answers
957 views

Spatial reference for dummies?

Can anyone recommend a good reference or tutorial that explains the principles of spatial references, projections, and coordinate systems? We are a small team of programmers working with GIS ...
1
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2answers
1k views

Coordinates of raster image from .TAB file

I have got a raster image (tif) from a mapping site and an associated .TAB file. I am trying to correctly map it into CAD/3d model - which I know is set up to the correct coordinates. The .TAB file ...
1
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1answer
323 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: ...
1
vote
2answers
525 views

Saving spatial reference of MapInfo TAB-file to file (like .prj)

I have some MapInfo TAB-file and I'd like to save spatial reference to .prj-file. How it can be done?
0
votes
2answers
720 views

Setting spatial reference for MapInfo tab-file

How can I change spatial reference for tab-file in MapInfo Professional?
1
vote
1answer
266 views

Importing a PostGIS and a Delimited Text layer in QGIS, not overlapping

I'm a beginner in QGIS, and I have a PostGIS database and a CSV file I would like to visualize. I followed the instructions in this question and the answers, but it doesn't work for me, my two layers ...
0
votes
0answers
37 views

Calculating ECEF X, Y, and Z velocities between 2 points on Earth [duplicate]

Possible Duplicate: How do I calculate ECEF X,Y,Z velocities for GPS if I have no satellites This is my third attempt at explaining what I'm trying to do. If I have two ECEF X, Y, Z ...
0
votes
2answers
94 views

Need Image with Sweref99_1800 projection/coordinate system

I need third party image tiles (probably world imagery) under sweref99_1800 projection and coordinate system (EPSG 3008). I found this link ...
1
vote
2answers
686 views

QGIS layers no longer overlay when Enable 'on the fly' CRS transformation is on

My QGIS project has two layers - one retrieved from GADM (administrative boundaries of Guinea Bissau) and another one of the villages collected in the field using GPS Decimal Degrees - D.ddddd. If I ...
2
votes
3answers
379 views

Dynamic Text for coordinate system

I would like to change the dynamic script for a coordinate system from "GDA 1994 MGA Zone 54" (Taken from a cut down version of the dynamic text>coordinate system) to "GDA 94 z54" How would I do ...
2
votes
2answers
403 views

What does 1:10m mean related to map resolution?

On Natural Earth they offer maps at various resolutions. What does 1:10,000,000 mean? Does it translate to the number of points per square meter or mile?
7
votes
2answers
2k views

How is EPSG:4326 data 'projected' in a 2D map?

I like to think I'm relatively well-versed in datums, projections, and coordinate reference systems, so if this is a stupid question I will suffer eternal shame. OpenStreetMap data is stored in WGS84 ...
0
votes
1answer
336 views

Generate a random 100x100 m bounding box in any projection in pure Python?

I'm given: Extend of WMS Layer SRS Now I want to, in standard 2.6 Python (no OGR or C lib dependencies), to generate a 100x100m random bounding box within that extent (assuming it is more than ...
1
vote
1answer
2k views

Adding EPSG:3857 / 900913 to Oracle's mdsys.cs_srs

I am working with an Oracle Standard database at version 11.2.0.1.0. I also have access to XE version 11.2.0.2.0. The later version has both SRIDs 900913 (Google Mercator) and 3857 (official Web ...
21
votes
4answers
15k views

Layers with same coordinate system should align/overlap but do not?

I put 4 different layers into my ArcMap document, but only one of them will show up on the map! I should be seeing the other 3 layers as well. When I do a Zoom to layer, I can see one layer, but I ...
1
vote
1answer
356 views

What datum (reference ellipsoid) does Nasa Worldwind use?

What datum (reference ellipsoid) does Nasa Worldwind use? I can't seem to find where Nasa Worldwind tells explicitly what datum they use. I need some sort of valid link.
3
votes
1answer
486 views

Using QGis for an imaginary plane world

I created an own map for my p&p rpg group and now I want to transfer it into QGis. That's easy to make, but I'd like to have an own CRS for that map but don't know how to use the right proj.4 ...
20
votes
1answer
1k views

What is most accurate coordinate system for calculating areas of polygons?

I have multiple polygons, all located offshore around the UK. I am trying to calculate the areas of these polygons in square kilometres, without splitting them by UTM zone. Is it possible to do this ...
2
votes
1answer
339 views

How to translate coordinates on the earth

I am trying to translate coordinates. I have a set of coordinates for city A which I need to map to city B, given a point P1 in city A maps to P2 in city B. How do I do this? This problem would be ...
2
votes
1answer
2k views

Projecting shapefile with transformation using OGR in python

I want to change coordinate system of a shapefile from British National Grid to WGS84 (in order to be able to convert it to KML later on). To get the best results of projecting I would like to use ...
4
votes
3answers
1k views

How can I find out how to convert this point to lat lon?

I have received a shapefile with measurement points to be analyzed, but no matter how I try, I can't find how to convert to lat lon. I suppose it would be good to know the projection but when I look ...
14
votes
3answers
2k views

Do ArcGIS SpatialReference object factory codes correspond with EPSG numbers?

I've got a project where I'm reading in geometry objects from text files to put them in ArcSDE. These geometry objects have an associated EPSG code, and I'm looking for a way to ensure they're in the ...
4
votes
1answer
293 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 ...