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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3answers
186 views

Copy>Paste from meter to feet coord-sys, and coordinates don't change in ArcMap 10

My dataframe coordinate system is in UTM with linear unit Meter. If I have a Polygon shapefile in a UTM coordinate system with a linear unit of Foot_US and I am sent a shapefile in the same UTM ...
3
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1answer
1k views

Add MicroStation dgn to ArcGIS/ArcCatalog 10.1

I'm an iOS programmer but new to using ArcGIS 10.1. I'm having a problem loading my MicroStation dgn file to ArcCatalog. I've connected the folder containing my MicroStation V8i roadway design dgn to ...
2
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2answers
397 views

Stripping spatial reference

I am creating an exercise for remote sensing students and would like to take an existing raster and remove the spatial reference from the file so that the students can practice using another image to ...
1
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1answer
391 views

Python GDAL/OGR: WGS84 & meters units

I'm dealing with shapefiles projected in: GEOGCS["GCS_WGS_1984", DATUM["WGS_1984", SPHEROID["WGS_84",6378137,298.257223563]], PRIMEM["Greenwich",0], ...
1
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2answers
650 views

How do you convert to degrees and minutes from 8/9-digit lat/lon DMS code? [duplicate]

I'm trying to map the national bridge inventory, but the coordinates are stored in this 9-digit code for longitude (and 8-digits for latitude) EXAMPLE: Longitude is 81°5.8' Code is 081054800 Page 9 ...
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3answers
1k views

Distance measurements across UTM zones: use geographic or planar approaches?

I have a survey grid spread across 3 UTM zones (36N, 36S, 37S). I want to find the nearest (or shortest) distances of the centroids of these grids to roads and various points between. It seems like ...
3
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1answer
344 views

Mapping latlng values to a point on a HRAP grid

I have a copy of some NWS rainfall data loaded into a PostGIS database. Given a lat lng point, I want to find the rainfall for that given day. The original data are in XMRG format and projected ...
2
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1answer
164 views

Why are towgs84 definitions missing on Ubuntu 12.04 compared to Windows?

Why for some of my most used CRS the 'towgs84' part of the definition of the layer spatial reference system is missing, compared to the QGIS for Windows? EPSG 3004, 23032, 23033 when used with QGIS ...
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1answer
52 views

Editor and projections ArcGIS

When opening an edit session Arc is telling me that some of my shape files' coordinate systems do not match the data frame. Here is the data frame coordinate system: Stereo_70 Projection: ...
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0answers
20 views

How to convert Rotated Polar grid raster to Non Rotated Polar Raster? [duplicate]

I have a RCM data which is in rotated Polar system , I want it to convert into non-rotated polar RCM. How can i do this things ? Please give some guidance
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1answer
130 views

Geometry has incorrect latitude-longitudes

SELECT ST_SRID(geom) AS s FROM zones GROUP BY s; returns a single record: 4326 SELECT Find_SRID('public', 'zones', 'geom'); returns 4326 SELECT AsText(geom) FROM zones returns geometry like: ...
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1answer
376 views

Geoprocessing tool not executing when Map's SpatialReference is Web Mercartor

I am facing a strange issue when trying to execute GP service when my map's spatial-reference is Web Mercator. I appreciate all help. I have a JavaScript API application. Initially I only had my map ...
2
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1answer
194 views

If I've given two different layers the same CRS, why won't they overlay one another?

I have a "towns" and "state" shapefile for Massachusetts as two separate vector layers in QGIS. I've set the project coordinate system to WGS 84 at the bottom of the screen (next to the "coordinate" ...
1
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1answer
40 views

Datums in compound CRSs

Is there some specific constraint regarding vertical and geodetic datums within a compound Coordinate Reference System (CRS)? E.g. if the ellipsoid model should be the same or not, or if the vertical ...
1
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1answer
78 views

Some terms related to coordinate

I was googling coordinate related information all the day. Now I am confused with some concepts and terms. I hope some one can help me to make it clear. Geographic coordinate system Geographic ...
2
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1answer
70 views

When is a projected length calculated via a pythagorean distance more accurate than an ellipsoidal length?

I'm using spatialite 3.0.1 with the following test data (in EPSG: 4326): Name astext(geometry) ---------- -------------------- Belitsa POINT(23.563 41.947) Malko Tarn POINT(27.533 ...
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0answers
41 views

what is the difference between the Geographic coordinate, transformed coordinate and screen coordinate [duplicate]

What is the difference between the Geographic coordinate, transformed coordinate(projected) ,cartesian coordinate, and screen coordinate? Is there a live example? And what is the association between ...
2
votes
3answers
5k views

Which CRS to use for Google Maps?

I am trying to map a Shapefile (download) onto a Google Map using the Javascript API. The Shapefile describes the boundaries of NYC School Districts. The file's projection was Lambert Conformal ...
9
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1answer
3k views

GDAL/Python: How do I get coordinate system name from SpatialReference?

In Python, using GDAL, I've extracted a raster's projection as a WKT string as follows: wkt = dataset.GetProjection() # wkt is ...
0
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2answers
232 views

How can I find the SRID from the WKT out of a GRIB file?

I have a grib2 file which I'm trying to import into PostGIS 2.0 Raster and process. Trouble is, I can't figure out what the SRID is supposed to be, or one close enough for government work. Running ...
0
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1answer
270 views

Is it possible to change dynamically the map spatial reference?

I have a map that uses ArcGIS Online in the small scales. So my map needs to be in Web Mercator in small scales. In the big scales, my web client Flex application uses some feature and map services to ...
0
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1answer
286 views

Why do points shift when reprojected from WGS84 to a state plane coordinate? [closed]

We have a Trimble unit we use to collect equipment. We collect the data in WGS84 and differentially correct it and then reproject it to a state plan coordinate system. The points always shift the ...
2
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1answer
229 views

Calculating points in the USDA's Cropland Data Layer coordinate system

I need to integrate against the USDA's cropland data layer. They've got a demo and some API docs. The important query I need to run is this, given an (x, y) of say (1551459.363, 1909201.537): ...
0
votes
1answer
254 views

“Request contains a format not offered by the server.” Error when using CRS transformation with WMS in QGIS

When I try to load a WMS layer which has a WSG84 as a default projection and use a CRS transformation on it, it gives this error message: Request contains a format not offered by the server. The WMS ...
3
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2answers
275 views

How to create georeferenced and projected data from hand-drawn map?

I am preparing datasets for students in a spatial statistics course for a module on spatial autoregressive models. We will use ArcGIS 10.1. The first dataset will correspond to a mythical ...
0
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1answer
56 views

Deleting QGIS CRS

I've created a new CRS on QGIS but I assigned a wrong name mistakenly to CRS's name. Now I have the CRS defined but the name of the CRS is wrong, or not easily identifiable. I was wondering if ...
0
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0answers
309 views

Getting: org.opengis.referencing.NoSuchIdentifierException: No transform for classification “Transverse Mercator Zoned Grid System” with geotools

Using geotools I've been trying to create a referenced envelope after converting/reprojecting from WGS 84 to UTM with specific zones and it seems that either I need to do something with authority ...
12
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2answers
2k views

Which function for creating a POINT in PostGIS?

When defining a Point in PostGIS, when do you decide to use which of the following? ST_SetSRID(ST_MakePoint(lon,lat),4326) ST_SetSRID(ST_Point(long,lat),4326) ST_SetSRID(ST_GeomFromText('POINT(lon ...
2
votes
1answer
961 views

PROJ4 C++ API: Amersfoort RD New to WGS84

I try to convert between dutch RD New (EPSG:28992) and WGS84 (EPSG:4326) via PROJ4 C++ API. On the console this works with: cs2cs +proj=sterea +lat_0=52.15616055555555 +lon_0=5.38763888888889 ...
2
votes
1answer
157 views

Why does a raster in Gauß-Krüger has a little offset to a shape in UTM?

I have raster data (TIFF files) where I think it's spatial reference is in Gauß-Krüger ("DHDN_3_Degree_Gauss_Zone_3") and some shape files in UTM ("ETRS_1989_UTM_Zone_32N_8stellen"). As you can see in ...
3
votes
1answer
1k views

What to set spatial reference to after projecting to GCS_WGS_1984

I have a shapefile containing some sort of vectors or polygonal chains. This file is in the GCS_CH1903 geographic coordinate system (it is not specified though... if I import it into ArcMap it says ...
1
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0answers
62 views

How to identify grid shift file used by osgeo in Python?

I wrote a Python script reprojecting points from a source coordinate reference system (SCRS) to a target one (TCRS) both identified by an EPSG code. I would like my python script to retrieve details ...
3
votes
1answer
84 views

What is displayed when I am using a geographic CRS for my project

I understand that each geographical dataset has a CRS, and that in order to overlay them, you need to either make sure that all datasets use the same CRS, or re-project some of them (or use on-the-fly ...
2
votes
1answer
556 views

What does 'projected bounds' and 'WGS84 bounds' mean in the definition of a CRS (on spatialreference.org)?

The site http://spatialreference.org gives 'Projected Bounds' and 'WGS84 Bounds' for each Coordinate System. What does these 'bounds' mean? e.g. for ETRS89 / UTM zone 32 N this is given: I know what ...
4
votes
2answers
235 views

How can I find an appropriate coordinate reference system?

I have a worldmap and need to present different countries (e.g. Japan and France) in different extracts in QGIS. Thus I need to find out the best way to decide for an appropriate CRS for the ...
1
vote
1answer
98 views

problem of buffering a point on large areas with a projected coordinate system

could someone clear this up for me please. i remember reading an article not long ago on the web about the problems associated with buffering points on a globe due to the fact that a globe uses angles ...
2
votes
1answer
313 views

How to get CRS of a raster layer in pyqgis?

I have this problem accessing to the coordinate reference system(crs) of a raster layer map. I wonder if such thing is possible? I have used this xml from GDAL open map service to load in a raster ...
2
votes
1answer
88 views

Ok to measure and union a projected-on-the-fly shapefile in ArcMap?

I have a dataframe in arcMap 10.0.4 that is of Africa Albers Equal Area Conic PCS. I bring in a census shapefile of WGS 1984 CS and it is projected on the fly. I do 2 things: I use the calculate ...
2
votes
1answer
55 views

why can I only define 6 custom CRS?

Using Q GIS 1.8.0 - I am trying to create several custom CRS definitions for the purpose of rectifying several split areas of a census shapefile. In the "Custom Coordinate Reference System Definition" ...
2
votes
1answer
163 views

Why does QGIS 1.8.0 crash when I try to set up CRS on Win XP?

I have a problem with my qgis 1.8.0. When I click on any button that set CRS or try to set the coordinates on the fly, qgis crash. I try to uninstall the program and re-install it again using ...
2
votes
2answers
262 views

Data points Imported into QGIS are in the middle of ocean

I'm new to QGIS and tried importing some GTFS data in the CSV format (stops.txt). The project CRS, base map CRS and GTFS CRS have all been set to Google Mercator, but the points that are supposed to ...
3
votes
2answers
921 views

Where is list of Geographic Transformations in ArcGIS, and their areas of applicability?

I have some data in Provisional South American Datum 1956, and I need to project it to Web Mercator with WGS84 as the datum. When I use the project tool in ArcGIS desktop, it requires a Geographic ...
0
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1answer
186 views

Openlayers Linestring over edge of map

im trying to create a route displayer for ships. But im struggling with the edges of the map. When going from ie. 179* to 2* it displays a line across the entire map, instead of displaying it on the ...
5
votes
1answer
316 views

Export spatial overlay from R package PBSmapping

After realising that the GEOS-library in Grass and the R package rgeos is incredibly slow, i found the packe "PBSmapping" to do the same thing, a Union of two Polygons and to cut the parts with no ...
2
votes
2answers
2k views

What Spatial Reference System do I store Google Map's Lat/Lng in

I am new to PostGIS, Spatial Reference Systems and projections and want to store lat/lng coordinates retrieved from Google Maps and Openstreetmap and its services like the Geocoder/Nominatim. I'm ...
1
vote
1answer
161 views

Modify CRS to match boundaries of shapefile

I have boundary data in WGS'84 lat/long and data in a custom generated CRS. The data in the generated CRS appears to be offset by a particular vector compared to WGS'84. I want to attempt to match the ...
2
votes
2answers
2k views

QPJ files on ESRI software

We have some GIS data, which was converted from AutoCAD dwg to TAB using mapinfo, then converted to shapefiles as that's what we are required to create. Editing the data fields was done in the shape ...
2
votes
1answer
179 views

How to fix distortions for Baden-Württemberg?

I'm working in an area in Baden-Württemberg, Germany. I loaded some OSM data in QGIS but the map display is distorted. I tried ftools define projection with many different projections but nothing ...
1
vote
3answers
697 views

How to create a spatial reference file

I am using python, arctoolbox and arcpy 10.0 I am running a script that is tied to an arctoolbox. The toolbox serves to enter in my parameters. I have a feature layer as an input. The feature layer ...
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2answers
766 views

MMQGIS: How to make grid layer in meters not degrees?

I've read several of the posts on here pertaining to MMQGIS Create Grid Layer option, but I have not found information on how to make the grid based on meters veres degrees. I know how to manipulate ...