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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1answer
14 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:
...
1
vote
1answer
45 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 ...
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0answers
15 views
Geoprocessing tool not executing when Map's SpatalReference 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 ...
1
vote
1answer
22 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
vote
1answer
30 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
32 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 ...
0
votes
1answer
34 views
Thiessen Polygons and Coordinate Projections
I am trying to perform a Thiessen Polygons analysis in ArcGIS 10.
My DEM is in GGRS_1987 and the point set I downloaded from Google Earth is in WGS_1984. The points display correctly but when I run ...
1
vote
1answer
156 views
Is it possible to convert data from WGS84 to Bessel1841?
When we convert data from bessel1841 to WGS84, parameter setting must be used because it is impossible automatic convert on QGIS.
Reference: Converting shp file from bessel1841 to WGS84
Is it ...
2
votes
1answer
46 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 ...
17
votes
7answers
513 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 ...
0
votes
1answer
27 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
42 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 ...
2
votes
1answer
58 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):
...
1
vote
1answer
46 views
Why do points shift when reprojected from WGS84 to a state plane coordinate?
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
67 views
geocoding addresses specifically into NAD1983 or converting X,Y into 1983 after geocoding
I'm going bananas trying to geocode addresses into a NAD1983.
I have ArcMap 10.1 and I'm using the default address locator (North American 10.0 from arcgis online). No matter how low I set the ...
3
votes
1answer
47 views
Best way to create a georeference and projected data from a hand-drawn maps of mythical village for use in spatial stats training modules
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 ...
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0answers
19 views
Switching between different feature sets / Change orientation of Openlayers Map
Setup
Entities postgis table:
id | name | the_geom | campus_id
1 | bldg_1 | <b1_geom> | 1
2 | bldg_2 | <b2_geom> | 2
3 | bldg_3 | <b3_geom> | 1
4 | bldg_4 | ...
2
votes
3answers
176 views
How to handle layers with different Spatial references in ArcGIS Runtime SDK WPF?
I am currently writing the "Zoom to Layer" function for my application. However, the spatial references between my imported layer and my base map is different?
Is there a way around this? Can I some ...
1
vote
1answer
48 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
50 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
81 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
20 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 ...
0
votes
1answer
73 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 ...
4
votes
2answers
75 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 ...
5
votes
1answer
93 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 ...
1
vote
1answer
47 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 ...
0
votes
0answers
16 views
Program to read Microstation CRS definition file (.dty)?
Are the other programs/tools (beside MicroStation) that can read MicroStation coordinate system definitions stored in .dty files? It seems to be a binary only storage format and I can't decipher it ...
1
vote
1answer
614 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 ...
2
votes
1answer
43 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 ...
3
votes
3answers
695 views
How to define ITRF 92 and ITRF 2008 using Proj4 parameters in QGIS?
I know how to define a CRS, but this particular one is giving me a headache. I was unable to find the EPSG code at spatial reference.
The main reason for asking this is that raster and vector data ...
2
votes
1answer
47 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" ...
1
vote
1answer
26 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 ...
1
vote
1answer
65 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 ...
0
votes
0answers
12 views
Units of Geometry & Geography data type [duplicate]
When you store data using the Geography data type (like in PostGIS), is it always in lon/lat in degree decimals?
For the Geometry data type, what are the units used in the coordinate pairs? Can it ...
1
vote
2answers
155 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
36 views
Modify CRS to match boundaries of shapefile
I have boundary data in WGS 84 and data in a custom generated CRS. The data in the generated CRS appears to be offset by a particular vector. I want to attempt to match the generated CRS projection ...
2
votes
1answer
102 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 ...
14
votes
7answers
4k views
ArcCatalog 10.0 complains that spatial references don't match between a feature dataset and a feature class that have the same coordinate system?
I have a feature dataset that is using the GCS_WGS_1984 as the geographic coordinate system. It includes a few feature classes.
This feature dataset is itself in a file geodatabase that contains a ...
2
votes
1answer
55 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
98 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 ...
1
vote
1answer
541 views
How to convert Lat & Long from Onemap.sg to Google Maps
I have a set of address for Singapore, I would like to take the Lat & Long from onemap.sg (SYV21: X, Y / Easting, Northing) and then store it in my databse , convert into (WGS84: Longitude, ...
9
votes
0answers
447 views
ArcGIS Length and Area Calculation Scenarios
Trying to get a handle on how length and area are calculated in different scenarios in ArcGIS. I don't know why I can't find a answer on the feature class fields, but I can't find a precise answer, ...
2
votes
1answer
52 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; ...
0
votes
0answers
36 views
Default CRS in QGIS isn't applied to new layers
I've set my CRS settings in QGIS to to use OSGB (EPSG:27700) wherever possible.
However when I create a new shapefile layer this setting is not applied and I have to manually select the CRS.
...
0
votes
1answer
52 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 ...
6
votes
1answer
74 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 ...
5
votes
1answer
595 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
90 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
50 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
55 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 ...
