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.

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2answers
131 views

Difference between latitude and longitude

It occurred to me that latitude and longitude are not homologous in that the lines of latitude lie on parallel planes or slices through Earth, while lines of longitude are not parallel and meet at the ...
4
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1answer
344 views

Python libraries for correlating Photo to GPX file?

Can anyone recommend a Python library(s) that can geotag a photograph with the lat/long coordinates by correlating the timestamp of the photograph to the timestamp of a waypoint within a GPX file? I ...
4
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1answer
249 views

How to create cohesive Spatial Pixels from Spatial Points Dataset

I have a Spatial Point DF spo (covering an irregular shaped area of interest). The data are not on a regular grid due to crs transformation. My goal is a raster with predefined resolution and extent ...
3
votes
3answers
2k 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 ...
3
votes
5answers
2k views

How to find coordinates for a lot of locations based on the town or village name?

I have got an Excel spreadsheet with roundabout 15,000 locations, which are only identified by the towns or villages name and the country. I am intending to present these on a world map. Therefore, I ...
3
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2answers
834 views

What kind of coordinate system is this?

I have a csv with a list of the world sea ports and their coordinates. The coordinates are in this format: 5234N 00226W How can i convert this to decimal Latitude / Longitude ? Data source
3
votes
1answer
287 views

Given a Lat and Lon, identify if the point is over land or ocean?

In R, what is the quickest way to identify if a point is over land or ocean? e.g. for: set.seed(0) lat <- runif(10, -80, 80) lon <- runif(10, -180, 180) points <- expand.grid(lat, lon) ...
3
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2answers
4k 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...
3
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2answers
3k 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({ ...
3
votes
1answer
847 views

Interpolate undulations for given points using a geoid model

I have two databases, the first one (F.tsj) contains gps points: coordinates and ellipsoid heights and the second one is simply a geoid model where every line stores latitude, longitude, and ...
3
votes
2answers
1k views

Looking for Python module to do lat lon calculations

I'm looking for a Python module that can provide some / all of the following services using latitude/longitude to define points: Distance between two points Point in polygon Distance along a ...
3
votes
1answer
77 views

PostGIS strange difference in distance calc from different point defenitions

I have a working POSTGIS database, loaded Dutch CBS data using shp2pgsql and now I want to map lat,lon coordinates to multipolygons. All examples I see use lon lat coordinates but if I do so I get ...
3
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2answers
170 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
votes
1answer
142 views

How to convert these mapping coordinates

I have an older database at work and I've been asked to map the recorded GPS coordinates for each record. Unfortunately, I can't figure out the map coordinates that were recorded. As an example, ...
3
votes
2answers
160 views

How to output coordinates from a shapefile to a GMT or CSV file in QGIS?

I want to get the coordinates for a line shapefile as csv or gmt files. I click create "new layer" - "new shapefile layer" - I check the "line" box and then "OK". Then I make my shapefile. When I ...
3
votes
1answer
81 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 ...
3
votes
1answer
3k views

How to manually edit point coordinates in QGIS?

Is there a tool for shapefiles or a QGIS plugin available, which will enable me to edit the coords of a point manually ? ("tool" -f1 "Tsunami Gauge"-move x1.abcdef -to x2.ghijkl) I do have ...
3
votes
2answers
2k views

Update point coordinates in QGIS after manually moving locations in edit mode

I have imported point coordinates from a database, but I need to manually adjust a lot of the locations. Is there a way for QGIS to automatically update the point locations in the attribute table ...
3
votes
2answers
137 views

Calculate geometry on some features have same X and Y for start and end?

I did "Calculate Geometry" on a line shapefile to obtain the coordinates X and Y for the start and the end of all the lines of the shape. But some lines resulted with the same X on the start and on ...
3
votes
3answers
682 views

Formula for coordinates (lat, lon), azimuth and distance.

I would like to know how to find a set of coordinates on a small circle some distance from another point. For example, lets say A = (39.73, -104.98) #Denver B = (39.83, -106.06) #point ...
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
3answers
809 views

Converting coordinates: Feet to Degrees-Minutes-Seconds

I have a point shapefile and I want to get the coordinates for each point in Degrees-Minutes-Seconds format. When I use Add XY Coordinates (Data Management) it gives me the coordinates in Feet format. ...
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
votes
1answer
2k 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 ...
3
votes
1answer
6k 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 ...
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
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
3answers
139 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
3k views

How to find X,Y coordinates of a single point in ArcMap 10.1?

I have a shapefile of a road layout (name: US-101). I drew a line across the road section which intersects the left and right edges of the road and pavement marking (which is also the part of ...
3
votes
1answer
197 views

How to center the map based on some (x,y) in QGIS?

I want to center and recenter the map loaded on QGIS using constantly changing (x,Y) Point. How should I do this using some code? My GPS device will write (x,y) to a text file. From there I get (x,y) ...
3
votes
1answer
88 views

How can I label both coordinates in mmQGIS?

How can I label both coordinates in mmQGIS? Everything I try leads to only one of the 2 coordinates (lat or lon) to be labeled. I cannot get both labeled at the same time.
3
votes
1answer
137 views

Is it possible to update only latitude or longitude in postgis?

I have a postgis database that contains Points created based on a couple (longitude, latitude), and I need to update only one of those two for a given point. I found that it's possible to do so but ...
3
votes
1answer
287 views

How to determine error radius of given points

I am running QGIS 1.8.0 on a 64-bit Windows 7 platform. Given multiple points with different (but close) coordinates, how do I automatically create a new point that programmatically takes into ...
3
votes
2answers
528 views

How to transform coordinates to location in x-y grid in R?

I have a polygon with a 40m diameter and several points that lay inside it. Now I want to reformat the point locations (projected in DHDN/GK-3, but could vary) to x-y coordinates ranging from zero to ...
3
votes
3answers
552 views

I have a list of coordinates that make up a route - how can I easily render this shape on a map?

Additional info - I don't need this to be on a map - I just need the shape of the route. Is there anything that can return that shape easily? The list of coordinates are in an xml document and I'd ...
3
votes
1answer
206 views

Enter 4 Coordinates and get a Polygon QGIS

Is it possible to enter 4 Coordinates for getting a Polygon. I have to Clip lots of exact rectangles and i was just wondering wether you know a plugin. Thanks a lot danke! Alex
3
votes
1answer
499 views

How Can I Calculate Time from Coordinate?

For my application I am searching for an API or an algorithm for clicking point time and time zone. I dont know how I can do this but after getting time I want to calculate giving coordinate sun ...
3
votes
1answer
166 views

Online/offline tool for collection of coordinates for simulation purposes

Is there any good free online tool to collect coordinate positions given, say a trajectory; or a polygon. For example, retrieve all coordinates between two points, every 500 meters. Many thanks.
3
votes
1answer
68 views

How to know the coordinates in a grid?

I have a raster (a catchment area) and a weather station with its coordinates (imported as .txt in ArcGIS) in UTM system. I want to know which row and column of my grid belongs to this station. How ...
3
votes
1answer
354 views

How to get X and Y coordinate values of the map?

I want the upper right and lower left coordinate of the exposed portion of the map, and for the whole map. What is the way to do this?
3
votes
1answer
41 views

From LiDAR .txt to QGIS map

I have Lidar data in .txt files (1000 to 26000 KB), where 2nd column marks x-coordinates, 3rd col y and 4th col z. 8 485000.16 6508997.48 1.84 66 Last 2 485001.27 6508998.92 1.86 82 Last 2 485001.02 ...
3
votes
1answer
51 views

Is there a method to tell which hemisphere a point belongs to, in WGS84 geoid, where the equator is an arbitrary ellipsis?

I use the WGS84 geoid (because I'm working with a GPS chip). I define an ellipsis that splits the surface in two parts, lets name these 'A' and 'B'. This ellipsis is defined by two points 'a' and ...
3
votes
2answers
208 views

Converting lat lon into co-ordinates (in ft of m)

I have a set of latitude and longitude of a series of points which specific the trajectory of a vehicle. If I consider the first point as the origin (0,0), is it possible to convert the trajectory ...
3
votes
2answers
1k views

How can i select a polygon in MS SQL 2008

I am very new to MS SQL 2008. I got a task to select a polygon from the polygon layer by giving the X-Y coordinates. I already got the script for PostgreSQL for the same thing, but i need it for MS ...
3
votes
1answer
200 views

Natural Earth: How to get the position of each country?

I've just split the 1:10m Natural Earth countries into individual JSON files which I plan to render and partially stitch back together using RaphaelJS. The 1:10m map is very big (10mb or so) so ...
3
votes
1answer
707 views

Why does gdalwarp return incorrect corner coordinates for my geotiff?

I have a png source image that's in Lambert Azimuthal Equal Area and I have the long/lat extent. So I ran gdal_translate to create tie points and convert to gtif. Then I ran gdalwarp to reproject to ...
3
votes
0answers
69 views

QGIS 2.8 PrintComposer, no coordinates shown

I tested under MacOS 10.10.3 and 10.9.5 now: In the QGIS v2.8 Print Composer I don´t get coordinates shown when I want to create a map sheet and activate "Draw coordinates". I can do all settings ...
3
votes
0answers
65 views

Given distances from two locations how to accurately find geographic coordinates [duplicate]

I am working on a research problem which requires me to calculate a geographic location accurately (with error distance of few meters), given distances from two geographic locations. For instance: ...
3
votes
3answers
368 views

How to add XY coordinates (latitude/longitude) to a DEM raster in ArcGIS 10.1

I would like to add xy coordinates of about 10 sites to a raster. I am using ArcGIS 10.1 and my xy coordinates are on Access 2013 database - saved as .mdb. The steps I have taken so far: 1) In ...
3
votes
0answers
111 views

Unknown gridlines on old Greenland base map!

Can anyone help me out please? I'm using an old 1:10,000 base map of Greenland for a mapping project with nice 10cm gridlines already drawn on. However it uses a coordinate system which is unfamiliar ...