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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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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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 ...
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1answer
6k 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 ...
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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 ...
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2answers
80 views

Difference between CoordinateSystem and CoordinateReferenceSystem in GeoTools?

What is the concept of Coordinate Refenrece System. You know GeoTools has a FeatureType class having getCoordinateReferenceSystem() function and also a CoordinateReferenceSystem class having ...
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58 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 ...
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3answers
302 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 ...
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2answers
119 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 ...
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83 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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167 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 ...
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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 ...
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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 ...
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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
427 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 ...
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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 = ...
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2answers
958 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
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1answer
411 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 ...
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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 ...
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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 ...
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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 = ...
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179 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 ...
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94 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?
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2answers
66 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 ...
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2answers
666 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 ...
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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 ...
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2answers
228 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 ...
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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 ...
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3answers
246 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 ...
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4answers
428 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 ...
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2answers
95 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. ...
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1answer
298 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 ...
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1answer
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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 ...
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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 ...
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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 ...
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2answers
417 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 ...
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4answers
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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 ...
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2answers
445 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": ...
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1answer
76 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 ...
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2answers
163 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?
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1answer
85 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: ...
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2answers
81 views

EPSG:3575 projected bounds

I've been trying to find out what the projected bounds are for EPSG:3575 but have not been able to find a definitive answer. Normally, I'd just use the values from EPSG.io but when I tried these in ...
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1answer
100 views

Using Cassini-Soldner projection in QGIS?

I have a shapefile in a Cassini Soldner reference system centered in Monte Mario (Italian cadastre map). I want to insert these data inside QGIS in order to compare data with aerial images. When ...
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1answer
31 views

Do I need to transform wind vectors when changing projection from EPSG4326 to EPSG24373?

I have a set of points and polygons given in "normal" lat/lon coordinates EPSG4326, which I need to transform to EPSG24373. I can do this without problem using PROJ4. However, I also have wind ...
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1answer
79 views

USA Contiguous Albers Equal Area Conic to miles

My data is in USA Contiguous Albers Equal Area Conic projection. How can I convert the USA Contiguous Albers Equal Area Conic projection to miles?
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2answers
61 views

Compensating lat/long offsets after conversions

In my application I am doing conversions between two different formats of data. First format is a simple one containing NE and SW coordinates for a given rectangular area: area = { "sw": { ...
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2answers
68 views

Points in Polygon Query but having CRS issues (QGIS)

I have two files: A csv file that has lat longs listed for points. A shapefile that contains England NHS CCG boundaries (which usually uses the British National Grid). When I 'add a delimited ...
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3answers
190 views

Find CRS (coordinate reference system) based on known location and coordinates?

Is there any tool or any tutorial which would help me to figure out CRS (coordinate reference system) from related information? In my particular case I know only the system is in meters, has origin ...
3
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1answer
314 views

Best Practice for HTML5 Geolocation with ArcGIS for Javascript API

My organization would prefer to use its own basemaps rather than those provided by ArcGIS Online due to the accuracy of information that is represented in them. The area we service is rapidly ...
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1answer
230 views

Comparing printed nautical charts to GPS coordinates

I'm just getting my head wrapped around the various geodesic systems. I have some (printed) Finnish nautical charts I'm trying to match to GPS coordinates. Given the number of underwater obstacles, ...
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1answer
179 views

Help with “projected XY to screen xy” conversion algorithm?

I'm trying to convert coordinates from any given coordinate system (be they the coordinates of a graph figure or a map, meaning they can span across both negative and positive values across any of the ...