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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2answers
137 views

Difference between CoordinateSystem and CoordinateReferenceSystem

What is the concept of Coordinate Refenrece System. You know GeoTools has a FeatureType class having getCoordinateReferenceSystem() function and also a CoordinateReferenceSystem class having ...
3
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1answer
80 views

Is it possible to define a custom CRS for a shapefile in QGIS that uses hundredths of a US foot?

I have several polygon shapefiles whose coordinates are defined as 100x their original coordinates projected from the Washington State South HARN State Plane in us-ft (EPSG 2927). I would imagine the ...
3
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1answer
115 views

Obtaining length of non projected feature (gcs_wgs_84) in meters instead of decimal degrees?

I could not find a post which answered to my problem and I hope I didn't miss it, in case I did I apologize. I'm working with Arcgis 10 and I have a multiple lines feature with gcs_wgs_1984 ...
3
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2answers
201 views

Can't find correct coordinate system: UTM83 Zone 15 forcing input in meters; need it to be read in feet

Forgive me, I'm a CAD person, and am very new to GIS. I've searched google and this site extensively for an answer, with no luck. My problem is that I was given a large number of sistered Raster ...
3
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3answers
1k views

Can someone clear up a lat/long issue? with google maps/arcmap

I know a bit about lat/long, projected and geographic coordinate systems etc, and a bit about geodesy and datums, but I would like someone well informed to help me out. I have a lat-long in ...
3
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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 ...
3
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1answer
150 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?
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1answer
5k 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 ...
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2answers
1k views

Coordinate system of a MODIS file to be introduced in GDAL for transformation

I am working on MODIS data using GDAL. When I extract coordinate system information of the files I got this: Coordinate System is: PROJCS["unnamed", GEOGCS["Unknown datum based upon the custom ...
3
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1answer
420 views

How to programmatically determine whether a spatial reference factory code is valid?

I am using the following code segment to create a spatial reference. spatialReferance = arcpy.SpatialReference() spatialReferance.factoryCode = spatialReferanceFactoryCode ...
3
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1answer
7k views

Changing the coordinate system of a qgis layer to the projection of Google Earth

I want to know how to change coordinate value of a vector layer (13293061,-572595) to 119.413,-5.13677 (vector data & Google Earth do not match). If I output my data using Google Earth as ...
3
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1answer
5k views

Lat/Lon/Alt to spherical or cartesian coordinates

On my previous question, it was advised I convert lat/lon/altitude to spherical or Cartesian coordinates. I'm not working near the poles and it would be safe to assume a spherical earth. What would be ...
3
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1answer
61 views

CRS not embedded by maptools in R

I'm using the maptools package in R to merge some data to a shapefile. When I open the original input shapefile in QGIS, QGIS automatically picks up on the CRS. When I open the output shapefile from ...
3
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3answers
347 views

How to georeference a map in UTM / WGS 84 (geographic) to WGS84 / UTM?

I have scanned UTM WGS 84 toposheets, with a geographic grid. I want to georeference them in WGS 84 / UTM (therefore with UTM coordinates). Should I: Calculate the UTM coordinates from the ...
3
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2answers
122 views

CRS reprojection

I am trying to change the CRS of one shapefile that is originally in NAD27 to WGS84 in Qgis 2.6. When I proceed to make the change, I still continue to see the file in UTM coordinates... I've tried to ...
3
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2answers
216 views

Convert a grid file from one set of coordinate systems to another

I have a grid file in a certain coordinate system. I'd like to change it so I have the same grid in geographic lat/long based on WGS84. This seems like something that gdal can tackle quite easily ...
3
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1answer
85 views

Help identifying a coordinate system

I have some "latitude" and "longitude" data that describes the Silverstone motor racing circuit in the UK. The coordinates look something like this: latitude longitude +03124.27986 +00061.07652 ...
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2answers
172 views

Convert data to another Coordinate Reference System

Assuming I've a point like this : POINT (751318 9760879) This point is in EPSG:27700 coordinate reference system. How do I convert the point to display in a map with EPSG3857 coordinate ...
3
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2answers
3k views

How to convert 6 & 7 digit coordinates to degrees latitude & longitude

I'm a bit new to the whole GIS world, and though I am making great headway drawing polygons and such in Bing Maps, I am currently stuck. In our SQL spatial data, I came across MULTIPOLYGON data, where ...
3
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2answers
2k views

which is the suitable Geographical Coordinate System and Projected Coordinate System for India

I want to create a spatial data for entire India, usually I use WGS84 as GCS and UTM zones for PCS in the places in India, but when I have to create the spatial data for entire India, I get confuse ...
3
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1answer
1k views

Are these two OGC WKT projections the same? And if so, why are their reference strings different?

So here is the .prj text of a federal shapefile dataset of all public airports in its native OGC WKT format: ...
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1answer
457 views

How to get spatial reference of a shapefile using python?

I always use arcpy.GetParameterAsText to get the spatial reference from the user. There should be a way to decide what is the spatial reference of a shapefile but I can't find it. Something like ...
3
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1answer
1k views

How do I get the coordinates of my data frame always in long/lat?

I want to determine the coordinates of my current data frame. To do so I wrote this script: def DataFrame (): mxd = arcpy.mapping.MapDocument("CURRENT") df = ...
3
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2answers
1k views

Python script to read coordinate system of an input feature class? [duplicate]

How to read the coordinate system of an input feature class in python script. How we can use "Describe()" function and tool validator for that purpose
3
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1answer
430 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 ...
3
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1answer
1k 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 ...
3
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1answer
3k 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
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1answer
2k views

MS SQL Server's STDistance output differs from Google Earth/Maps straight line distance

I am testing SQL Server STDistance function in the following way: DECLARE @g geography; DECLARE @h geography; SET @g = geography::STGeomFromText('POINT(53.553813 9.99158)', 4326); SET @h = ...
3
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1answer
95 views

How do I figure out the length of polyline features in a feature class with a WGS 1984 coordinate system?

I'm trying to figure out lengths of polyline features in a feature class with a WGS 1984 coordinate system. Here's code to list lengths: >>> import arcpy >>> inFc = ...
3
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1answer
209 views

Canadian Geodetic Vertical Datum of 2013 (CGVD2013)

"Natural Resources Canada (NRCan) has released the Canadian Geodetic Vertical Datum of 2013 (CGVD2013), which is now the new reference standard for heights across Canada. This new height reference ...
3
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1answer
97 views

Unknown Spatial Reference after Georeferencing in ArcMap

I am trying to georeference an image base on another *.tif, after rectifying i still have my Image as unknown spatial reference. Does somebody know how I can fix it?
3
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2answers
69 views

Digital Elevation Model and Shapefile not aligned in openWind

I have a digital elevation model and a shapefile containing point features for the location of wind turbines. These two layers appear to be aligned in QGIS but when I open them in openWind, they are ...
3
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2answers
749 views

Reprojection of shapefile in R and final extraction of values

I need to extract values from some raster files (stack) using a shape file. to bring both of them in the same CRS, I first transformed the shapefile using the EPSG codes. Opening it in an GIS software ...
3
votes
3answers
5k views

Converting from an x-y coordinate system to latitude/longitude

I'm building an indoor wifi-based tracking system that can calculate the position of a device in meters relative to the sensors distributed throughout the building. So far I've gotten to the point ...
3
votes
2answers
236 views

Creating raster pinned to cartesian coordinates using ArcGIS for Desktop?

I'm looking to create a raster such that the edges of the raster are aligned perfectly with the cartesian coordinates of the underlying projection. I am using a custom Lambert conformal conic ...
3
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1answer
2k views

Calculating distance scale factor by latitude for Mercator

This was really inconvenient topic to google out - so I'm asking for clarification, did I understood things correctly. I'm talking about measuring short distances in Mercator projection (3857). You ...
3
votes
3answers
253 views

How to read coordinates with variable Gauß-Krüger zone (meridian) in QGIS?

Is there a sensible way to visualize coordinates like this as point layer in QGIS? X values starting with 2 are EPSG 31466, 3 is 31467 and 4 is 31468. I didn't try, but i think the same problem will ...
3
votes
4answers
448 views

what is the suitable projection coordinate system for Iran

I am doing analysis for province wise Iran. I am using WGS1984 as my geographical coordinate system, and I do not know which is suitable Projection coordinate system for entire Iran. I feel the UTM ...
3
votes
2answers
96 views

Mixing coodinate systems

I'm planning to create an online map with openlayers (2 or 3) or leaflet. I have to show some points/markers (~30.000), polygons (~500) and lines in an area of ~10x10 kilometers in several layers. ...
3
votes
1answer
319 views

QGIS display does not reflect projection

I have slight experience with ArcGIS, but am new to QGIS. I'm trying to set the projection of my map, and I understand that this is done by altering the CRS (coordinate reference system) of each ...
3
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1answer
1k views

Setting coordinate system in PostGIS

The geographical information data that INEGI (part of the Mexico's goverment) provides are in the following coordinate system (or is projection?) Lambert Conformal Conic, double standard parallel ...
3
votes
2answers
360 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 ...
3
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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 ...
3
votes
2answers
425 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 ...
3
votes
4answers
5k views

WKID (Well Known ID) for national projection for ArcGIS REST API

I have to use my national projection system which does not have corresponding WKID listed for ArcGIS REST API. Without it I am unable to use this projection system for my web application. Any ...
3
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2answers
446 views

Trying to load this map service from ArcServer.. its on our own system but its not working… or I don't have access

Can anyone see this? http://gis.co.frederick.va.us/ArcGIS/rest/services/TestSDEService/MapServer Spatial reference is.. var initExtent = new esri.geometry.Extent({ "xmin": ...
3
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1answer
32 views

Projected coordinates for Well-known ID 5232 cannot be found in ArcMap?

Projected coordinates for SLD99(WKID- 5232) cannot be found in ArcMap Coordinate system. Is there any built in procedure to find that original coordinate system in ArcMap 10.3? If not what is the ...
3
votes
1answer
85 views

Problem with distance in QGIS

I start a new project with base on OpenLayers plugin but if I check the distance on QGIS with distance tool (I choose a straight road) I view 5.466m on QGIS and 4.300m on google (by walking). How is ...
3
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2answers
212 views

Is WGS84 a Coordinate system or projection system? [duplicate]

WGS84 is often referred to as a "projection system" and sometimes it is confusing to me about what a "projection system" is and where WGS84 falls in one. Could someone please clear that up for me?
3
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1answer
87 views

What system do these coordinates use? (from LinkedGeoData.org)

I have extracted these coordinates from geolinkedata And I don't know what system they are using: (-15.4400797 28.131791000000003) What I know is that they correspond with these WGS84 Coordinates: ...