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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313 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
178 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.
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2answers
1k views

Looking for a tool that will place the cursor to a specific x,y coordinate

I am a new user to Quantum GIS. I am looking for a tool/function that will allow a user to type in coordinates, and place the cursor on that exact position. This is for navigation in the field... ...
3
votes
1answer
204 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
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2answers
3k views

Extract coordinates from vector layer in PyQgis

In Qgis, I have made a polygon, and from that polygon I have made a vector grid via research tools-> vector grid. The grid covers the entire polygon. Now I want to extract these grid points in the ...
3
votes
1answer
373 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
666 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 ...
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3answers
660 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
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1answer
268 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
3k views

Dynamic scale bar, coordinates and grid for map frame in Mapinfo map layout

I am looking for a dynamic scale bar and coordinates (grid) for map frame in the map layout of Mapinfo. To make it clear I am talking about separate scale bar in layout which is not part of map ...
3
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1answer
597 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 ...
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1answer
168 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.
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1answer
77 views

Point Coordinates Conversion with unknown system

I've been using QGis for few weeks now. Although this site always came very helpful, I can't find solution to my recent problem: I have few points, and know their coordinates in "WGS-84" and "ISN-93" ...
3
votes
1answer
70 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
400 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
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1answer
50 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 ...
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1answer
73 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
225 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
214 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
805 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 ...
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0answers
33 views

GPS points displaying in the wrong place

I'm trying to help a student by importing an excel table of Lats and Longs into Arcmap, but they are displaying in the wrong location - I am also a bit suspicious of the coordinates. I imported the ...
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0answers
122 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 ...
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votes
0answers
419 views

Inserting coordinates from Google Maps into a Database

My question is pretty basic. I am using Android Google Maps to take the coordinates off a location on the map and I want to insert it into a PostgreSQL database. I know I have to use PostGIS but how ...
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0answers
67 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: ...
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votes
1answer
424 views

Determine when I have crossed state line?

We are currently using the Google Maps API to get route information and total mileage but we would like to determine when we are crossing into a new state. When we return the route information we can ...
3
votes
2answers
430 views

Plotting X, Y coordinates generated from MySQL database in QGIS

Currently running QGIS 1.8.0 on Mac OS X 10.8.4. I can plot points on a map using the "Add delimited text layer" plugin to get x-y coordinates from a text file. However, I'd like to be able to ...
3
votes
0answers
125 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 ...
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votes
0answers
418 views

How to Batch Change X, Y Coordinate Number in ArcGIS?

I have a huge number of points (100000 points). Some of these have the same x,y coordinates. For example, 50 points are same in x,y then 100 points are same in another x,y coordinates and so on. ...
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2answers
832 views

Stripping spatial reference

I am creating an exercise for remote sensing students and would like to take an existing raster and remove the spatial reference from the file so that the students can practice using another image to ...
2
votes
2answers
13k views

ArcGIS: Create polygon using file containing point coordinates

I have a text file containing the projected coordinates of the points that define a single polygon. The X, Y coordinates are separated by Tab Is there a tool in ArcGIS similar to "Add X,Y Data" in ...
2
votes
1answer
288 views

Wrong lon and lat

I am using QGIS 2.2.0! I have shape file with wrong coordinates, it's had replaced x coordinate with y coordinate. For example my point feature have coordinates: 4830698,7496859 and right coordinates ...
2
votes
3answers
1k views

ST_MakePoint or ST_PointFromText to generate points

I'm new to postGIS and am having trouble finding an answer to this question. I have loaded UK postcode data (OSGB36, SRID 27700 with eastings and northings fields) into a postGIS database. I now want ...
2
votes
3answers
710 views

Looking for map calibration software and city database

I'm in need of a mapping software which, given a map, lets you calibrate it (choose which geographic coordinates project to which pixels on the map image) and then given a database of cities, you can ...
2
votes
1answer
143 views

Coordinate system doesn't contain values in the range -180 to 180 and -90 to 90

I'm creating an android version of a PC program (I've contacted the company who owns the PC program, so it's legal). The program is in the core a GPS, but is used to navigate pre-defined routes for ...
2
votes
1answer
612 views

Getting First and Last Point coordinates of Polyline with Field Calculator in ArcGIS Desktop?

I'm trying to get the First Point coordinates (x,y) and Final Point coordinates (x2,y2) from a polyline in ArcGIS 10 with the Field calculator. I've added 4 (double) fields like StartX,StartY,EndX ...
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votes
3answers
2k views

how to extract a rectangle corner coordinates in python script

i want to extract a rectangle corner coordinates of a shape file in python script..please suggest me a solution. Thanks in advance, Bhavya
2
votes
1answer
1k views

How to unproject coordinates on a Google map with Openlayers?

Below is my code and a pic. When I finish making my circle on a Google map with Openlayers, I get the following coordinates but I want coordinates like E.G: bottom: -27.762124575762 left: ...
2
votes
1answer
106 views

Uses for “Calculate Geometry” option

Is there another use for "Calculate Geometry" aside from calculating area, length and points? I already read the help section ArcGIS Help (10.2, 10.2.1, and 10.2.2) and it's very informative. ...
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votes
2answers
537 views

How likely is it that Smartphone Camera GPS coordinates are wrong?

According to the coordinates printed directly on this photo of my late son Kelvin here: https://www.dropbox.com/sc/w6tvwuvbosuh9rk/AADzT-3vDXcFQ9LnKK1BYMZUa ...and the Exif data from the .jpg: ...
2
votes
1answer
840 views

EPSG:4326, EPSG:3857, JOSM and unprojections

It is said here that EPSG:4326 is not a projection. In my mind, a projection is a transformation of the surface of the Earth producing a flat image, notably a bitmap. We know that WGS84 (World ...
2
votes
1answer
430 views

How do you calculate positional accuracy in qgis?

How to you compare two layers in QGIS to get the positional accuracy?
2
votes
3answers
613 views

C++ coordinate class that automates projection?

Can anyone point me to a C++ class for representing coordinates that automatically handles projection transforms? What I'm thinking of is something that would allow me to create vars that incorporate ...
2
votes
1answer
399 views

Convert Garmin or iPhone weird GPS Coordinates

I am trying to find a way to convert over 500 locations I have saved in my Garmin iPhone GPS app (iPhone 4S using Garmin StreetPilot v2.7), but I can't find a way to convert these coordinates as they ...
2
votes
2answers
347 views

Switch coordinates in linestring

I made a silly mistake: when creating linestrings in my PostGis database i inverted the lon and lat values. Which isn't a problem for postgis itself, but for my visualization and intersections. ;) Of ...
2
votes
3answers
824 views

Ordnance Survey 1 km Grid

I am wanting to get a copy of the OS 1km Grid layer. I have found these previous questions: Ordnance Survey grids - download or generate? and Ordnance Survey Grids But neither provide the ...
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2answers
2k views

Converting from local coordinates to coordinates GPS?

i am working with business object tool traying to make a kml file to be imported on google maps. I dont know much about geographic systems, but i begin to understand some basic things. I have a ...
2
votes
1answer
410 views

If I've given two different layers the same CRS, why won't they overlay one another?

I have a "towns" and "state" shapefile for Massachusetts as two separate vector layers in QGIS. I've set the project coordinate system to WGS 84 at the bottom of the screen (next to the "coordinate" ...
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votes
4answers
1k views

Query Postgis Table with PHP

Would you be so kind as to help me with the following in OpenLayers. I need to be able to use the coordinates from a user click in a postgis query. To catch the coordinates of a click I built a click ...
2
votes
1answer
3k views

Convert X Y Pixels to Easting Northing

I'm trying to find out what the formula would be to convert the X, Y of an image to the Easting and Northing coordinates. I've downloaded some of the raster maps from OS UK web site and I'm looking ...