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.
5
votes
1answer
609 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 ...
1
vote
1answer
97 views
Change coordinate system in multiple MXDs ArcGIS 9.3 using Python
I have to loop through some folders which may contain *.mxd files and change their coordinate system. I already found this piece of Python which should do the trick for ArcGIS 10.x (from here):
...
1
vote
1answer
54 views
Why would a map lost the coordinate system when I use it in ArcGis?
I have a file in AutoCad with ETRS89 coordinates, and when I use the same map in ArcGIS it loses coordinates. With other files do not happen.
2
votes
1answer
60 views
Setting coordinate systems in QGIS: “transform error caught”
I'm learning how to use QGIS (v 1.8.0 "Lisboa") on Mac OS 10.6.8. My goal is to create a simple county map of Illinois using the base data shapefiles available from the Illinois Natural Resources ...
4
votes
2answers
146 views
Setting coordinate systems in gvSIG: Is the workflow similar to QGIS?
I am still learning how to use coordinate systems and projections, but I hope this basic question will be easy to answer. My goal is to be able to use either QGIS or gvSIG to create a simple county ...
5
votes
1answer
162 views
Does anyone know the proj4 Coordinte Reference System command line for Rectangular Polyconic Gores?
I am a GIS beginner using QGIS 1.8.0
I am trying to transform a world map from the standard WGS84 Coordinate Projection System to a set of rectangular polyconic gores, with a gore count of 12.
...
2
votes
1answer
61 views
QGIS mixing up CRS
I´ve just started working with QuantumGIS for my thesis. I ordered shapefiles with the CRS: ETRS 89 UTM Zone 33N, but QGis layer properties now shows the layer has a different CRS (namely SWERE99 TM) ...
6
votes
2answers
231 views
Why do my Shapefiles not align correctly?
First: I'll summarize what I understand so far so please confirm or correct me.
When On-the-Fly is selected a layer is re-projected from
that of the layer's CRS to that of the project CRS, IF
...
3
votes
1answer
96 views
What are the highest and lowest precision Coordinate Reference Systems for US East Coast?
And does it matter what system your data layer begins with if you choose the right system for your project? Do some applications use more precise projection systems than others?
4
votes
1answer
50 views
Unknown Old Coordinate System of the Phillipines
I am reading a report made in 1979 and the coordinates show N 46,400 and E 47, 600. This is in the Philippines. Would anybody know what the coordinate system was used in this numbers? Thanks.
3
votes
2answers
121 views
Is there any online tool for converting coordinates between different EPSG?
Every time I want to do conversion, I need to get into the console to run proj.4. Is there any online tools for converting coordinates between different EPSG?
0
votes
1answer
87 views
Geostationary satellite projection to be introduced in GDAL
I'm working on raster files and their spatial reference system is:
PROJCS["Geostationary_Satellite",
GEOGCS["GCS_Unknown datum based upon the custom ellipsoid",
DATUM["D_Not specified ...
0
votes
1answer
76 views
CRS Conversion problem
My question is quite simple, this is probably why I couldn't find a conclusive answer anywhere.
I have two datasets representing the same area in Romania, but in different CRS, A is local, B is WGS ...
2
votes
1answer
244 views
Which coordinate system and projection shall I use for georeferencing google map image in ArcGIS?
I have saved Google Maps image (not Google Earth) of area at latlon(17.692437,83.218689) by some method in jpeg format. It is an exact snapshot of the Google Maps. Now I need to geo-reference it to ...
2
votes
1answer
54 views
Need to convert from ISpatialReference to SpatialReference
I am attempting to write a method in C# that will accept as input, an ESRI.ArcGIS.Geometry.ISpatialReference object and convert it to an ESRI.ArcGIS.Client.Geometry.SpatialReference object. I need ...
1
vote
1answer
64 views
Why are the areas covered by 2 Universal Polar Stereographic (UPS) coordinate different?
According to http://en.wikipedia.org/wiki/Universal_Polar_Stereographic_coordinate_system. the area covering Arctic is less than Antarctic. Any reasons for it?
It is due to the shape of the lands?
21
votes
3answers
12k views
Algorithm for offsetting a latitude/longitude by some amount of meters
I'm looking for an algorithm which when given a latitude and longitude pair and a vector translation in meters in Cartesian coordinates (x,y) would give me a new coordinate. Sort of like a reverse ...
0
votes
1answer
45 views
Is it possible to download GPX another coordinate system except WGS(GCS) with GPS Tool on QGIS1.8.0?
I got GPS data with using bessel1841 as coordinate system.
When I download GPX data on GPS tool, it is automatically treated as WGS84.
Can I use another coordinate system when I download GPX on GPS ...
0
votes
1answer
88 views
Why are layers not overlapping to each other inspite of having same CRS? [closed]
I am new to QGIS and working with QGIS 1.7.3 version, I have my all layers in WGS 84 CRS but even though they are not overlapping to each other, What should I do ?
0
votes
0answers
59 views
What kind of unit of measurement for scale does SQL Server 2012 Spatial use?
What kind of unit of measurement for scale does SQL Server 2012 Spatial use?
2
votes
1answer
50 views
How to get a list of all projections that are currently available in QGIS via the PyQGIS-API
i'm building a QGIS-Plugin and i want the user to choose a CRS out of a combobox in which the coordinates he would enter into some textfields are represented, so these can be converted into another ...
3
votes
1answer
226 views
Raster incorrectly reprojected to OSGB(27700)
Ubuntu 12.04, QGIS 1.8.0, GDAL/OGR 1.7.3, GEOS 3.2.2
Open a Spatialite db with OS Mastermap poly layer (EPSG:27700);
Add OpenLayers Plugin (1.0) from QGIS offical repository;
Add a Google Satellite ...
1
vote
1answer
822 views
MapGuide and Google Maps Coordinate System problems
I'm trying to do a simple MapGuide OS + Fusion overlaying Google Maps and I can't figure out why the coordinate system are off. I downloaded populated places from natural earth.
After Googling, it ...
5
votes
2answers
433 views
Location of Coordinate Systems folder in ArcGIS 10.1
To make it easier to find and select the 3 or 4 coordinate systems we use most often in ArcGIS 9.x and 10.0 we would copy them to the top of the Coordinate Systems folder, generally located in ...
4
votes
1answer
175 views
Can I say WGS84 is more accurate than NAD83 in terms of their reference ellipsoids?
Other than its application, can we say the reason of common adoption of WGS84 is due to its accuracy?
3
votes
1answer
161 views
getting the specified geographic transformation, or at least the GCS, of a data frame
First, the TLDR digest:
I'm getting a bogus value from dataFrame.geographicTransformations on some machines; how do I get the correct value as shown in the properties dialog? and/or
Given a spatial ...
6
votes
7answers
1k views
How can I digitize a PDF image?
I have an image file in pdf format which includes some drawings (lines, closed areas, and points). I want to digitize it into a shapefile so that I can show it on a Google map. I have a couple of ...
8
votes
3answers
4k views
Coordinate System Transformation in ArcMap
For the Data Frame Properties on a map in ArcMap, what is the difference between selecting a new coordinate system and using a Transformation?
0
votes
0answers
109 views
How to represent clustering of geographical points on map in STATA?
I've plotted a map on STATA using user-written program spmap and have also obtained the grid for my space using spgrid program. Now I want to see where most of my data points are clustered on map. Is ...
2
votes
1answer
103 views
Problems with NAD27 projection in QGIS
I have some data that is in NAD27, but I am having a hard time displaying it in QGIS. I think that the problem is with the CRS. I cannot seem to find the correct NAD27 option. The closest one seems ...
4
votes
1answer
83 views
Problem with custom projection definition in Qgis
I want to define a custom crs valid for Mexico. The context is that older cartography in Mexico is based on the NAD27 datum. I wanted to test the following proj4 string
+proj=longlat +ellps=clrk66 ...
3
votes
1answer
496 views
Convert GPS coordinate to ArcGIS x,y point?
I'm trying to plot some AGSSimpleMarkerSymbol's in a AGSGraphicsLayer. The issue I'm running into is that the data I'm starting with are GPS coordinates (lat/lon). I'm using AGSPoint to plot the data, ...
1
vote
1answer
177 views
matching georeferenced jpg with GPS data in WGS84 [closed]
I have imported my georeferenced jpg which I believe (on the basis of metadata in xmml file) to be in the NZGD2000 TM coordinate system.
metadata:
Origin:
1.76759e+06,5.94938e+06
Pixel Size:
...
3
votes
1answer
453 views
What is the relationship between ITRF and WGS84?
Why are there people saying that "I am using WGS84(ITRF96)"?
There are newer version of ITRF. Will WGS84 follow it?
If so, what will be the influence to us?
2
votes
0answers
40 views
Spatial indexing of a point pattern in R [duplicate]
I have a point pattern and a tessellation (grid) in R. Is there a way to spatially index each of my points? In other words, my tessellation grid has n quadrats, I would like to know for each of my ...
0
votes
0answers
52 views
What's the difference between CRS 4326 , CRS 4978 and CRS 4979?
They are all based on WGS84. 4326 is called "geographic 2D", 4978 is called "geocentric", 4979 is called "geographic 3D".
What are the differences between these three?
Why are we using "geographic ...
8
votes
1answer
167 views
Reprojection - Learning the ins and outs
I would like to expand my knowledge coordinate systems, projections and reprojecting data, with a view of writing a reprojection engine.
Could you provide me with some resources (books, websites, ...
6
votes
1answer
135 views
Coordinate system in aerial imagery
I am calculating WGS84 coordinates of points in an aerial image, given the WGS84 coordinates of the center of the image and the ground distance width and height (calculated from altitude and lens ...
8
votes
1answer
255 views
How can I see the coordinate transformation parameters in QGIS?
How can I see (and edit if possible) the transformation method and parameters used by QGIS for "on-the-fly" transformation, and then for saving data in another CRS? Like in ArcGIS?
Here is the ...
9
votes
9answers
4k views
Batch convert lat longs to UTM?
I've got a .csv file that contains a long list of latitude and longitude points. Is there an efficient way to batch convert the list into a projected UTM coordinate system?
Thanks.
5
votes
1answer
102 views
How do I make the scalebar accurate when I am working with a google satellite image in QGIS?
I start a project in QGIS. I set the CRS to anything (in this case I use EPSG=26918 a NAD83 datum). I also enable on the fly projection. Then I import a vector. In this case a kml, which I believe is ...
5
votes
1answer
77 views
Where is the Spatial reference ID stored in SpatiaLite?
I have loaded a shapefile into a SpatiaLite Database using the spatialite-gui. In which table is the Spatial reference ID or EPSG code (of the stored data)stored in SpatiaLite?
2
votes
1answer
315 views
Converting geographic coordinate system in R
I have points in geographic coordinate system and I wanted to convert them to swiss grid (CH1903+).
Sample data:
id lon lat
2 7.173500 45.86880
3 7.172540 45.86887
4 7.171636 ...
5
votes
1answer
155 views
How to Display the World Map in Projected Coordinate Systems
I am trying to create a simple presentation map and I download the global level country boundaries shapefile from http://www.diva-gis.org/Data. The layer coordinate system is in Geographic Coordinate ...
0
votes
1answer
167 views
QGIS 1.8.0 - Define shapefile as UTM 15 NAD83 Feet
I have a shapefile which the .prj file says it is
...
2
votes
1answer
302 views
How to speed up this simple MySQL points in the box query
MySQL doesn't have nearest neighbor search so. So I try to come up with a "distance" that's reasonable so the number of returned query is around 20-200.
That way innodb doesn't have to compute ...
7
votes
2answers
497 views
Nearest point on a line ( Spherical / Mercator projection )
I have a line (Ax,Ay - Bx,By) over a mercator projection (google maps) and a random point (Cx,Cy) nearest to that line, i would to know the closest point (transparent blue on the image) over that line ...
3
votes
2answers
2k views
Convert X,Y State Plane coordinates to decimal degrees
I have 1000's of data point I need to convert from North Central Texas 4202 into Lat/Long decimal degrees. Can someone give me a conversion equation so I can quickly convert using excel? I have only ...
2
votes
1answer
220 views
Reprojection from WGS to Slovenian Gauss Kruger in QGIS
I have gpx file (track) in WGS84 (EPSG: 4326) coordinate system from Garmin GPSMAP 62 which is right projected in BaseCamp and MapSource. When I save track as *.GPX and import it to QGIS and use ...
2
votes
1answer
93 views
What are the geometric principles and GIS techniques that I can use to generate a postcode coverage of my city at street scales?
Postal codes of Brazil and another countries are oriented to distribution logistics, and improvement of reliability in writing the postal addresses; but without much concern for the spatial ...
