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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2
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1answer
73 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 ...
0
votes
0answers
43 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 ...
3
votes
3answers
6k 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
votes
1answer
4k 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
votes
2answers
268 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
votes
1answer
320 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
votes
1answer
363 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
votes
1answer
288 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
292 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
votes
2answers
352 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
votes
1answer
69 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
350 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 ...
14
votes
2answers
3k 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
1k 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
171 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 ...
4
votes
1answer
2k 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
vote
0answers
70 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
96 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
701 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
311 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
106 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 ...
3
votes
1answer
399 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
96 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
56 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
171 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
331 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
1k 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
votes
1answer
225 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
377 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
186 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 ...
3
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
226 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
856 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 ...
3
votes
1answer
476 views

Which Geographic Transformation to use for WGS_84 to D_Sphere?

I have a shapefile for world countries and I want to reproject it from GCS_WGS_1984 to Sphere_Eckert IV. However, it asks for Geographic Transformation; it says this is optional but it is required in ...
1
vote
2answers
922 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 ...
1
vote
1answer
69 views

Extent is zooming map to 0,0 in ArcGIS API for Silverlight?

When I use this code (from the example): ESRI.ArcGIS.Client.Geometry.Envelope myEnvelope = new ESRI.ArcGIS.Client.Geometry.Envelope(); myEnvelope.XMin = -130; myEnvelope.YMin ...
2
votes
1answer
338 views

Which BC Albers should I use and is there any difference?

I was about to calculate the area of some polygons and before I did I did some research. I found that the area of the polygon will be represented in the units of the projection used. So I did some ...
2
votes
3answers
753 views

Coordinate System (Malaysia RSO Projection) not lining up in QGIS and ArcGIS for Desktop?

I am using QGIS 1.9.0 on Linux Mint; and I am new to (Q)GIS I have three layers (2xshapefiles, 1xopenlayer[Bing Maps]) that I am trying to line up located in peninsular Malaysia. Shapefile_1 is a ...
1
vote
1answer
87 views

Shapefile CRS damaged. How to bring it back?

I have two shapefiles with same location and extends (EPSG 4326). But one of the shapefiles CRS seems to be damaged after doing a lot wrong with reprojection... its not shown on the same position as ...
0
votes
1answer
342 views

CRS is UTM 51, the coordinates are shown in meters, show same coordinates as lat long as well?

We are working with a CRS of UTM 51N, the Philippines. The coordinates under cursor are shown as metric values. Clients however like so see the Latitude Longitude values when they move the cursor. Is ...
3
votes
1answer
162 views

How to bulk import ESRI projections into Postgis

Where can I get a file that would allow me to bulk upload all of the ESRI projections into the spatial_ref_sys table of postgis. I know that you can get insert statements on spatialreference.org; ...
6
votes
1answer
118 views

Should I Reproject Data Which Has Been Captured Incorrectly?

I'm working on a project for a client which is migrating data from an Oracle database to an ESRI Geodatabase. When data for this project was initially captured over 15 years ago, the coordinate ...
0
votes
1answer
666 views

ArcGIS Desktop, shapefile and EPSG code

Why a shape file with CRS WGS_1984_UTM_Zone_22N en Arcgis has a differrent prj file than the EPSG:32622:WGS 84 / UTM zone 22N WKT ? Can I replace Arcgis .prj file with EPSG:32622 WKT ...
1
vote
1answer
1k views

Convert latitude longitude coordinate to x y coordinate?

I'm using a postgis database and java to develop my application. I need to transform my geographic data currently in latitude/longitude format into a x/y format. I found solutions based on UTM ...
1
vote
1answer
272 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
94 views

Setting coordinate systems in gvSIG: workflow or transformation issues

I am learning how to use gvSIG 1.10 (Mac OS 10.6.8 Snow Leopard). My goal is to create a simple county map of Illinois using the base data shapefiles available from the Illinois Natural Resources ...
2
votes
1answer
172 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 ...
1
vote
1answer
108 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.
5
votes
2answers
1k 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. ...