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.

learn more… | top users | synonyms (3)

3
votes
1answer
382 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
votes
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
votes
2answers
937 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
votes
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
votes
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
votes
1answer
135 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
votes
1answer
83 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
votes
2answers
62 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
votes
2answers
471 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
4k 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
204 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
votes
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
228 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
368 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
92 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
253 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
votes
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
votes
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
311 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
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 ...
3
votes
2answers
380 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
4k 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
votes
2answers
443 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
votes
1answer
61 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
votes
1answer
24 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 ...
3
votes
1answer
59 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
votes
2answers
58 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
votes
2answers
52 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
votes
3answers
141 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
267 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
198 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
147 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
79 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
125 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
votes
1answer
120 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
votes
1answer
538 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 ...
3
votes
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, ...
3
votes
1answer
4k 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?
3
votes
2answers
354 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
votes
1answer
42 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 ...
3
votes
1answer
36 views

How to manually add spatial reference information for FEWS rainfall data in ArcMap?

I am trying to match rainfall data from USGS/FEWS to coordinate locations of survey households in Uganda, so I will need to be able to project the rainfall data. So far, I downloaded the dekadal RFE ...
3
votes
2answers
84 views

How to define layer's CRS and avoid the CRS dialog in PyQGIS?

There is an existing Shapefile, which I want to add. At the moment my code looks like: self.iface.addVectorLayer(self.shpFilePath, "Track", "ogr") It works fine, but i want to define the crs ...
3
votes
2answers
124 views

methods for converting coordinate datum and format in python?

Related to an earlier Q&A of Missing grid shift files for cs2cs.exe? ... what are the various methods to convert coordinate datum and format in python? (Windows Vista, python 3.4) For example, ...
3
votes
1answer
100 views

Reprojecting between NAD27 and WGS 84 part III

I am trying to perform a reprojection for data with datum Nad27 to WGS84 datum. According to AndreJ in some previous questions in Stackexchange (CRS reprojection for instance) QGIS uses internally by ...
3
votes
2answers
48 views

Running Point To Raster has output coordinate system different from input?

I need to transform a DEM from a Point-Feature-Class (Shape) to raster (GRID). For that I'm using the tool 'point to raster' and it works perfectly. The only problem is that it seems to change the ...
3
votes
1answer
93 views

Transforming coordinates from one projection to another

var bounds = config.init_center.transform( new OpenLayers.Projection("EPSG:31466"), new OpenLayers.Projection("EPSG:3857")); console.log(config.init_center); console.log(bounds); I have ...
3
votes
1answer
140 views

Clearing data frame projection of current mxd using ArcPy?

I am required to open a bunch (50 per week) of mxd's and 'Clear' the Coordinate system from the data-frame to make sure my students have all of their data projected in the same (correct) Coordinate ...
3
votes
2answers
69 views

Generic Grid to Coordinate System

I have been given a large dataset of X,Y positions of animal movements in a generic grid system. It uses 0,0 as an origin and then position units are in feet from origin. I have the geo-referenced ...
3
votes
1answer
56 views

How to define custom projection EPSG:5714 in QGIS

I have a series of raster files with the CRS EPSG:5714. I need to define this CRS in QGIS but I'm fairly new to this and have no idea how to define the proj4 CRS for this. I searched at ...