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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2
votes
1answer
796 views

Getting polygon shapefile node coordinates and point order

I am trying to get the coordinates of each node of a polygon in QGIS. What I basically did is use the following tools: Vector -> Geometry tools -> Extract nodes Vector -> Geometry tools -> Export ...
0
votes
0answers
133 views

OpenLayers maxExtent

I've displaying Ordnance Survey UK tiles in OpenLayers using a TMS Layer the scales are using are 1000K, 250K, 50K and 10K. I've set the maxExtent to 0.0, 0.0, 700000.0, 1300000.0 which is working ...
2
votes
1answer
110 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 ...
0
votes
2answers
721 views

How to extract elevation data from binary .ADF elevation format at given coordinates?

I have a high resolution digital elevation model available. The ground resolution is 1 meter and the file format is adf which is some binary ESRI grid raster format. I have a script the outputs x/y- ...
0
votes
0answers
703 views

Unable to dynamically locate map boundary coordinates in OSM/Leaflet

I have been trying for the past hour to take the coordinates of the map edge in a OSM/leaflet application I am making. While I can get the coordinates of the center, and I can get the coordinates of ...
2
votes
2answers
719 views

Converting OSM_ID to coordinates

I have downloaded some open street map data from Webgeo, but instead of coordinates it came with an "OSM_ID". I cannot seem to find any data dictionary or information about this variable on the web. ...
3
votes
1answer
2k 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 ...
0
votes
1answer
310 views

How to convert drawn vector feature from EPSG:900913 to EPSG:4326

My script allows you to drawn shapes on an openlayers map, and then to get the WKT information from that shape, except the returned coordinates are in 900913 and i need them to be in lat/lon. thanks
0
votes
0answers
71 views

How to transfer absolute node position to latitude and longitude? [duplicate]

I am new to gis and also a newbie using QGIS. I have got a Layer with one shape. I extracted the nodes from the shape. Now I have got the absolute X and Y value of my Layer in the attribute table. ...
1
vote
3answers
170 views

Copy>Paste from meter to feet coord-sys, and coordinates don't change in ArcMap 10

My dataframe coordinate system is in UTM with linear unit Meter. If I have a Polygon shapefile in a UTM coordinate system with a linear unit of Foot_US and I am sent a shapefile in the same UTM ...
1
vote
1answer
270 views

ArcMap 10.1 - UTM Zone Display Mismatch

I've recently noticed that the UTM zone displayed in the Identify box and the "Goto XY" box display a different UTM zone than the one I'm in. I'm working in WGS84 NAD83, Zone 13N but when I use the ...
2
votes
2answers
292 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 ...
1
vote
2answers
474 views

How do you convert to degrees and minutes from 8/9-digit lat/lon DMS code? [duplicate]

I'm trying to map the national bridge inventory, but the coordinates are stored in this 9-digit code for longitude (and 8-digits for latitude) EXAMPLE: Longitude is 81°5.8' Code is 081054800 Page 9 ...
2
votes
1answer
459 views

What is the formula to convert WGS84 coordinates to EPSG 2163?

I'm looking for the formula which converts wgs84 coordinates to epsg 2163. I know that QGIS can do the calculations but I need the exact formula. Cheers!
0
votes
1answer
192 views

Drawing on jpg-map image with proj4 (perl)

From the point of view GIS professionals this question will be sure very primitive, but please keep in mind - i'm totally newbie in this area - and this is my 1st question here. Have several GPS ...
1
vote
1answer
156 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" ...
24
votes
2answers
1k 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 ...
2
votes
1answer
984 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 ...
2
votes
1answer
183 views

Calculating points in the USDA's Cropland Data Layer coordinate system

I need to integrate against the USDA's cropland data layer. They've got a demo and some API docs. The important query I need to run is this, given an (x, y) of say (1551459.363, 1909201.537): ...
1
vote
1answer
246 views

generate random world point geometries

I have a world map. I need random point geometry. So, how can I randomly generate point coordinates? Any programming language. Also, I am using SRID 4326. Any programming language.
1
vote
0answers
1k views

convert GPS to XY coordinates

if i have obtain GPS coordinates as Latitude/Longitude, then i need to convert them to XY coordinates, i see this link actually i need to get the Trilateration , in its equation i need the XY ...
1
vote
3answers
2k views

Openlayers vector feature coordinates are not transforming,

I have a OpenLayers vector with a single feature [0]. It's coordinates are in the map projection (EPSG:3413) and I want them in WGS84 (EPSG:4326) decimal degrees. I have the following code which ...
2
votes
1answer
1k views

Calculate View Angle

I am looking for the most accurate way of calculating the view angle (Azimuth, Elevation) from a reference point (my location) A to another point B. I have the Lat, Lon, and Altitude for each point. ...
1
vote
1answer
131 views

Polygon Nodes do not have separate coordinates [duplicate]

I'm attempting to measure the distance of a series of points from a smaller number of polygons. As a first step, I've changed the polygons into points along their border, via the Vector> Geometry ...
1
vote
1answer
480 views

convert GPS to x,y using reference node

i am using sensor nodes and their antenna to calculate GPS coordinates as notation of (degrees/minutes/seconds), i have some question of how to do these things: how can i convert latitude and ...
2
votes
1answer
157 views

Why does QGIS 1.8.0 crash when I try to set up CRS on Win XP?

I have a problem with my qgis 1.8.0. When I click on any button that set CRS or try to set the coordinates on the fly, qgis crash. I try to uninstall the program and re-install it again using ...
0
votes
3answers
331 views

clipping polygons (vector) map with a polygon (vector) layer

A frustrated newbie with QGIS Lisboa version in Windows 7. I want to clip a soil map (multiple polygon vectors) with a single polygon (rectangular polygon vector). The project projection is set at ...
3
votes
1answer
127 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, ...
2
votes
1answer
4k 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
3answers
4k views

Is there a way to populate a spreadsheet of city names with their latitudes and longitudes from Google Maps or some other service?

I have a long list of cities in the United States, and would like to get the coordinates for each city without looking up each one individually. Is there a way to do this?
8
votes
2answers
640 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 ...
1
vote
1answer
231 views

ROAD COORDINATES Data (CARDIFF)

Does anyone know how to get road coordinates data from openstreetmaps? I know its possible I just don't know how. Thank you!!
2
votes
2answers
1k 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 ...
1
vote
1answer
282 views

How to divide a certain country on a map into grids?

I want to divide a certain country into grids 1,2,3,..., which are divided equally - in other words, have the same width and length. Then, I want to know into which grid a point coordinate will fall ...
1
vote
1answer
513 views

I want to import an Excel spread sheet with desc, northing and easting into Google Earth to make a KMZ

I have a spread sheet with three columns containing a Description, a Northing and an Easting in UTM. Instead of entering the points in by hand, I want to find a faster method. Any help is greatly ...
2
votes
1answer
224 views

How to flip X and Y coordinates of a grid by GDAL

I have a grid, which has flipped X and Y coordinates (X is represented by Y values and Y is represented by X values). This results in grid being positioned in completely wrong place. How can I flip ...
0
votes
1answer
193 views

How to reproject WSF layer created from GeoJSON?

I have a WFS layer: myVecLayer_disp= new OpenLayers.Layer.Vector("Редактируемый участок",{projection: new OpenLayers.Projection("EPSG:900913")}); And i have feature store: var protocol=new ...
2
votes
1answer
3k views

How to get Shapefile point coordinates into .xls?

How can I get just Coordinates (in a file) from point features (shapes) without big hussle. Something like Shape to .xls, with distinct coordinates? I want to use this coordinates immediately, so GPX ...
6
votes
3answers
653 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 ...
2
votes
0answers
119 views

Interpolate current Course value of GPS using previous Course values

I have a set of GPS data with Lat, lon and Course. I need to interpolate current value of course, using previous values of Course. The formula I am using is not accurate in curves.In C language I was ...
0
votes
1answer
866 views

Wrong coordinates in data when projecting in world map (qgis) [duplicate]

Possible Duplicate: How to find the proper coordinate reference system with two sets of data using different measurements or too convert one system into another I'm fairly new to the GIS ...
2
votes
1answer
1k views

Is it possible to place a point at a coordinate in QGIS?

Is it possible to place a point at a coordinate in qgis? I have a map, using irish grid reference and wish to place a point at an exact 6 digit coordinate. Is it possible to do it. Previous to this ...
6
votes
1answer
461 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 ...
3
votes
1answer
208 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 ...
4
votes
1answer
300 views

How to fix incorrect coordinate data for the mouse's position

I am running Quantum GIS 1.8.0 on a 64-bit Windows platform. I've imported a data set that plots correctly when overlaid with a Google Satellite map, so I know that the layer/project CRS is okay ...
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 ...
2
votes
4answers
719 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 ...
3
votes
0answers
257 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. ...
4
votes
2answers
9k 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 ...
5
votes
1answer
314 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. ...