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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161 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
2k views

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

Sorry, but 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 ...
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1answer
972 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
415 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
918 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
404 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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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 ...
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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 ...
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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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1answer
159 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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1answer
89 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
65 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
583 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
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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 ...
3
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2answers
220 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
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3answers
236 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
410 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
94 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
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1answer
278 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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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 ...
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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 ...
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2answers
339 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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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 ...
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2answers
391 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
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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 ...
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2answers
444 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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2answers
115 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
82 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
67 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 ...
3
votes
1answer
88 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 ...
3
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1answer
29 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
72 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?
3
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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": { ...
3
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2answers
60 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 ...
3
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3answers
173 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
votes
1answer
296 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 ...
3
votes
1answer
215 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, ...
3
votes
1answer
162 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 ...
3
votes
1answer
102 views

How to align an HDF layer

Forgive me, but I am completely new to GIS. I am using QGIS. I have a raster layer (HDF format) that does not align with other layers. All layers are projected WGS84 (EPSG:4326) and still the problem ...
3
votes
1answer
134 views

Plotting spatial data when two spatial objects have different CRS

I have a spatial polygon object and a spatial points object. The latter was created from xy latlong data vectors (called latitude and longitude, respectively) in a dataframe, while the former was ...
3
votes
2answers
59 views

What is the closest CRS to “Meridiano de Greenwich”

I have a 1906 scanned map that I am trying to georeference in QGIS for Mac. The map has French and English lat-long, indicating them as either "Meridiano de Greenwich" or "Meridiano de Paris." I would ...
3
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1answer
124 views

Rhombus shaped pixels when viewing an image referenced in WGS84

Following the Question What is the projection of WGS84 in GIS software?, in the comments section of the answer http://gis.stackexchange.com/a/73578/5256, Jake very well explains that Because the ...
3
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1answer
568 views

QGIS Shapefiles have the same CRS but dont line up. (Census Tiger Data & State Data)

I have the Census Tiger data for Oregon from http://www.census.gov/geo/maps-data/data/tiger-data.html Then the bottom one of 2010 Census Population & Housing Unit Counts — Blocks. The shp ...
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2answers
2k views

Convert GPS coordinate to ArcGIS x,y point?

I'm trying to plot some AGSSimpleMarkerSymbol's in a AGSGraphicsLayer. The issue I'm running into is that the data I'm starting with are GPS coordinates (lat/lon). I'm using AGSPoint to plot the data, ...
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1answer
5k views

What is the relationship between ITRF and WGS84?

Why are there people saying that "I am using WGS84(ITRF96)"? There are newer version of ITRF. Will WGS84 follow it? If so, what will be the influence to us?
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2answers
360 views

Geographic co-ordinate system displayed as projected

ArcGIS suite of software categorises coordinate systems as either geographic or projected. From what I understand about coordinate systems (and I may be wrong), geographic co-ordinate systems are used ...
3
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2answers
38 views

How to fix the error between two coordinate systems?

How do you think the shift of line is due to morphological change of river? Or it is due to deviation between two coordinate systems? Please point out !!
3
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1answer
61 views

How to convert Chinese Beijing 1954 coordinates to WGS84

I have a series of coordinates for locations in Sichuan Province China that I need to convert so that I can use them in Google Earth. The coordinates are "1954 Beijing coordinates system" and show up ...