# Tagged Questions

Any of a set of two or more numbers used to determine the position of a point, line, curve, or plane in a space of a given dimension with respect to a system of lines or other fixed references.

7answers
45k views

### How do I create point features with exact coordinates?

How do I create point features with exact (manually entered) coordinates in QGIS? I get precise GPS coordinates from a survey team which I need to add to a point layer. What I want: -Add point, type ...
1answer
10k views

### Is WGS84 itself a Coordinate Reference System?

I was wondering the difference between WGS84 and EPSG:4326 (see this). Can then WGS84 on its own be defined as a Coordinate Reference System? Or is it just a datum so that a Coordinate System must ...
2answers
2k views

### Why do we use the terms “longitude” and “latitude” for a spherical body?

To specify a geographic coordinate we use the terms “longitude” and “latitude”. Far as I know, these terms derive from the Latin latitudo (= breadth) and longitudo (= length). In German we use the ...
5answers
49k views

### How to get coordinates from geometry in PostGIS?

This line: SELECT geom FROM myLayer.geom will return a hex value, i'm wondering how would it be possible to get decimal values, a result that look likes human-readable coordination? Regards,
6answers
26k views

### How to generate random locations nearby my location?

I am trying to create random locations nearby my location. What i want is to create random latitude/longitude pairs inside a 200 meters circle surrounding my location. This is the formula i came up ...
1answer
720 views

### What format is a location represented like this?

While converting an old system, I came across a position column with values in a format like this: 38RQT6410550656 While I've never seen global positioning represented this way, putting this in ...
4answers
11k views

### How to move vectors to specified coordinates in QGIS?

I have a layer of vectors located around, say, (100, 100), and I want to move them to new coordinate like (1000, 1000). How should I do it? Preferably using QGIS.
2answers
316 views

### How to create dynamic leader lines?

I'm trying to create dynamic leader lines by using a PostGIS view in addition to the QGIS „Move Label“ tool. CREATE VIEW leader_line AS SELECT gid, ST_MakeLine(geom, ST_SetSRID(ST_MakePoint(...
3answers
3k views

### Given a set of coordinates, how can I calculate the minimum bounds?

I have a set of coordinates in lon/lat. There are always at least 3 ordered coordinates that form a poly (if they were projected flat). How can I calculate the minimum bounds for these coordinates as ...
4answers
5k views

### How to use Z-Coordinate in QGIS?

I was mapping an area in Namibia and also tracked a lot of paths on my way with my Garmin device... so I thought it would be nice to see height differences in my area (esp. interesting in the raining-...
3answers
4k views

### What are the coordinates of the mysterious hole in Siberia?

I am interested in taking a Google Earth aerial view of the mysterious hole recently discovered in Siberia and perhaps doing some hydrological analysis of the area in a GIS. However, there appears to ...
2answers
4k views

### Leaflet: Container coordinates vs Layer coordinates?

What is the difference between map container coordinates and layer coordinates? From what I gathered, the map container coordinates are always relative to the map viewport, and while layer ...
2answers
288 views

### What's the difference between coordinateDimension and spatialDimension?

The OpenGIS standard mentions three methods to query the dimensions of a Geometry: dimension(): the inherent dimension of the geometry: 0 for Point 1 for Curve 2 for Surface coordinateDimension(): ...
2answers
2k views

### How do I group near points with GPS positions?

I'm an IT person so I don't know too much about projections and so on, I hope you can help me. I have made an application for Android that collects a GPS position, so I have the latitude and the ...
1answer
2k views

### Computational most efficient way to convert Cartesian to Geodetic Coordinates

As far as I understand the literature there are several ways to convert a set of geoecentric cartesian coordinates to geodetic coordinates Bowring, 1976 Borkowski, 1989 Lin & Wang, 1995 Toms, ...
3answers
6k views

### How to export polygon coordinates to CSV (not WKT)?

I am new to QGIS, and I am now trying to export polygon coordinates from a shape file to a csv file, but so far all my attempts have failed. I have found numerous questions and answers about this, but ...
3answers
26k views

### How to add Lat/long columns to a point layer which is not in WGS84?

I need to extract the Lat/long coordinates of the centroids of districts. My QGIS project SCR and the different layers have all been set on "WGS 84 / UTM zone 18N". I've created the centroids using ...
5answers
12k views

### Calculate midpoint from a series of latitude and longitude coordinates

I've got a series of longitude and latitude coordinates which represent a building outline e.g. -0.5485381346101759,53.2285150736142 -0.5482220594232723,53.22842450827133 -0.5482298619861881,53....
1answer
314 views

### Coordinates of cities and villages in The Gambia/Senegal

I am looking for sources of geo-referenced data on villages and cities (or all other things there are) in The Gambia (and Senegal if available). One issue with geocoding in rural West Afrika is the ...
2answers
2k views

### Exporting a set of lat/long coordinates to SVG

Suppose I have a set of coordinates in latitude and longitude. What would be the easiest way to export those to an SVG file? I'd rather do this programatically (any language or library will do) ...
4answers
183 views

### How do you programmatically read the coordinate display format in ArcMap?

I'm looking for a property (or properties) that will give me the display units and the formatting. I assume I need IMap.DistanceUnits but I can't find the formatting. Is this exposed? I am also ...
1answer
2k views

### Coordinate grid display on a rotated map

I have a series of maps that require me to rotate my data frame within my layout screen (north "rarely" points up in these maps). I ONLY want to show east coordinates on the top/bottom and ONLY north ...
0answers
1k views

### Calculating compass bearing between two GPS coordinates… with a twist [closed]

I'm building a virtual tour application that uses Google's streetview code to render the panoramas into a non-distorted view. Each panorama has 1 to n links where the user can select to move on. I ...
3answers
3k views

### Adding “noise” to overlapping X,Y coordinates so no longer in EXACT same place?

I have a series of points representing animal observations. Many of them overlap, having the exact same coordinates, and this is causing me trouble when I want to run some analytical tools which ...
3answers
345 views

### Waypoints with coordinates in R

I have a SpatialLineDataFrame with 20 observations of 4 variables (in WGS84). I want to create waypoints every 10 meters. Every waypoint will has the x y coordinates. I tried to do it manually like: ...
2answers
9k views

### List of central coordinates for all countries?

I need a list of the central points for all countries: China: lat/long (coordinates of the most central point in China) France: lat/long (coordinates of the most central point in France) etc...
2answers
1k views

### What does coordinate system WG 21° mean?

I have a land survey document for a piece of land, it contains absolute coordinates that I would like to locate on google maps, but I don't know how to correctly interpret the data. What does the "...
3answers
985 views

### Classifying point coordinates to countries or continents?

I have about 50 000 points (latitude and longitude), and I would like to find out in which country each of the points is located. It does not need to be super precise, though. (Or actually I only ...
5answers
4k views

### Calculating coordinates of square x miles from center point?

I am trying to create a x mile square (or circle) around a central point, where all sides of the square would be x miles from the centre. I need the 4 corner coordinates. It is scrambling my brain ...
1answer
239 views

### Descrambling scrambled coordinates?

I've got a data set that comes with coordinates, however they seem to have gotten scrambled somewhere along the way of data-collection, data-entering and data-export. For some of the places the actual ...
1answer
141 views

### Can I project a single set of coordinates that are not in a table or feature class with arcpy?

I have been searching for the easiest way to convert a single set of State Plane Coordinates (in units of "Feet") to Decimal Degrees using arcpy. All the methods I have seen so far involve one of the ...
1answer
12k views

### Making POINT from longitude/latitude coordinates in existing table using PostGIS?

I would like to make a POINT using the longitude and latitude columns of an existing table. Here's a link to the documentation of ST_MakePoint. Here's my table: CREATE TABLE sysinst.bio ( oid ...
1answer
359 views

### If Geographic Coordinates are unprojected coordinates, how can GIS softwares display such unprojected data on a plane?

I have been using ArcGIS and QGIS regularly for about 2 years now, and just recently I was struck by this new thought. If a data set in say, in ArcMap, has been georeferrenced with a Geographic ...
1answer
1k views

### Line vs. Polygon Intersection Coordinates

I am working with Python, Shapely and Fiona... Is there any way where I can give in an input of a line shapefile and a polygon shapefile, and get a result of the intersection points and their ...
1answer
875 views

### Coordinate system in aerial imagery

I am calculating WGS84 coordinates of points in an aerial image, given the WGS84 coordinates of the center of the image and the ground distance width and height (calculated from altitude and lens ...
2answers
24k views

### Convert X,Y State Plane coordinates to decimal degrees

I have 1000's of data point I need to convert from North Central Texas 4202 into Lat/Long decimal degrees. Can someone give me a conversion equation so I can quickly convert using excel? I have only ...
1answer
342 views

### Find shortest path between points avoiding shapefile?

I am an intermediate python developer with very limited GIS experience. I have a list of latitude/longitudes of a ship at sea. I need to join them into a polyline using the shortest distance between ...
1answer
655 views

### How do you fix Overlapping Lines?

I have a line dataset that contains some lines where the "end points" are actually found in the middle of the line. In the image below, the nodes are shown in green and one of the end points in red. ...
2answers
1k views

### How to get latitude, longitude and altitude database from a GeoTIFF file?

I am developing an AR iOS application. When the iPhone gets the current location, it has to calculate locally the visible point. I want to read the tiff files in my application, and then get the ...
2answers
2k views

### Shortcut to copy current cursor coordinates in ArcMap

Is there a shortcut or an extension to ArcMap 10 that would allow me to quickly copy (to clipboard) the coordinates at the current map position/click? I could implement such a functionality easily ...
2answers
3k views

### Measuring distance between points in ArcMap - what coordinate system to use?

This is a basic -newbie - question. I have some handwritten data points taken off a GPS - so I am assuming they are in WGS 84, and I want to load them in ArcMap 9.3, via excel, and measure the ...
2answers
21k views

### Calculate bearing between two decimal GPS coordinates

I'm building a virtual tour application that uses custom panoramas in conjunction with Google's StreetView service. With StreetView, you can have 1 to n links at each particular location to move to, ...
2answers
14k views

### Change OpenLayers 3 view center

I'm using OpenLayers 3 to interact with some maps. I first declare my map: map = new ol.Map({ target: 'map', layers: [ new ol.layer.Tile({ ...
2answers
665 views

### Accuracy of coordinates from 1960's

I have been provided with Lat/Long coordinates from a reference station recorded in 1969. When I plot the coordinates into Google Earth the location appears to be out by c.100m. Is this due to the ...
2answers
3k views

### Coordinates(Latitude, Longitude) are different at same place on iPhone and Android devices, why?

I used HTML5 code for getting coordinates on Android (HTC desire s) with GPS enabled and iPhone (3gs). But the latitude and longitude are different on both devices at same place, why?. Difference ...
1answer
382 views

### How often does Google change the geo-coordinates for a given address?

I geocoded the address "50 Hurt Plaza Southeast, Atlanta, GA 30303" twice. Once on July 28th, 2014 when I got the coordinates: (33.754208, -84.387272) And again today, August 18th, 2014, and got ...
2answers
2k views

### How to convert from one ellipsoid to another?

Introduction I have the following problem: I want to convert from WGS84 to "Anguilla 1957 / British West Indies Grid" (EPSG 2000). This seems to be straight-forward, as the transformation is a simple ...
1answer
3k views

### Understanding the difference between coordinates projection in OSM and Google Maps

I'm looking at the coordinate differences between Google Maps and OSM. I'm a noob in the technicality behind GIS. Having read: EPSG 3857 or 4326 for GoogleMaps, OpenStreetMap and Leaflet How to ...
1answer
1k views

### Convert from WGS84 to Google Mercator

I want to convert longitude and latitude coordinates from WSG84 to Google Mercator. The following code-samples show my coordinates in a KML/KMZ file and where I need the coordinates in the javascript ...
1answer
186 views

### Sending coordinates via VHF Radios to Computers

I need to send and receive coordinates in NMEA format from a VHF radio to a computer. Any suggestions where to look in order to accomplish this task? The transmission will occur only when the user ...