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
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4answers
416 views

Get coordinates from address

I am writing a application which allow users to save a address into database (db) and in the next step it shows all addresses on a map. But in the saving step I need automatically calculate a GPS ...
1
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2answers
301 views

How to extract features with specific coordinates from a ShapeFile?

I would like to extract a number of features from a ShapeFile which match with specific latitude/longitude values. I am interested if/how this can be done with QGIS and ogr2ogr. The output should be ...
1
vote
1answer
367 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
109 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... ...
2
votes
2answers
603 views

How can i convert from local coordinates to coordinates gps?

i don know if this is the right place to publish this. 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 ...
2
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0answers
89 views

Should 2D Positions and 3D Positions be considered conceptually different entities?

Let's suppose we want to model GeographicPositions, described by coordinates or coordinate tuples inside some Coordinate Reference System. Also, these would be put inside some sequence to represent ...
2
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0answers
135 views

Comparing two spatial datasets statistically

I'm new to this forum. I'm working on the following problem - I have two datasets. Let's call it dataset A and B. Both of them will contain a set of points like A1,LonA1,LatA1 A2,LonA2,LatA2 .. .. ...
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0answers
143 views

How to define coordinate system and geographic transformation for a CAD drawing?

I am a GIS guy and I occasionally work with CAD files as well. Now I need to know how I can define a coordinate system and a geographic transformation for a CAD Drawing. According to ESRI: "You can ...
1
vote
1answer
102 views

How to write a expression in field calculator for finding $X and $Y?

I'm trying to calculate the lat/long of points using the Q GIS field calculator.Nathan W suggested to First, save the layer as WGS84 and import it again. Then in the field calculator you can use $x or ...
1
vote
1answer
100 views

Insert geometric data to a column from coordinate values in double precision

Screenshot of database http://wp.me/aIW9p-i0 For table “households”, I want to create two new columns: 1) “Geom”, data type – geometry; 2) “WKT”, data type ‐ text; I am intending to do the following ...
0
votes
1answer
130 views

converting grid references to long/lat

If I import from a POST DB a set of points that are referenced by grid reference, will the long/lat decimal also be added to the file? or will I have to convert the points to long/lat myself? In ...
3
votes
0answers
89 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 ...
1
vote
1answer
103 views

How do I obtain layout coordinates of features using arcpy?

I just read the topic about Convert point XY to page units XY using arcpy? but I didn't find a solution to my problem. I have a point layer file, I know coordinates in map view, I'd like to know ...
2
votes
1answer
605 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
101 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
100 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
594 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
615 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
568 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. ...
2
votes
1answer
1k 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
257 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
70 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
164 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
207 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
234 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
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2answers
370 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
415 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
171 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
139 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" ...
23
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
820 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
167 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): ...
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1answer
199 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
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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
121 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
454 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
152 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
271 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
120 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, ...
1
vote
1answer
3k views

Make POINT from longitude/latitude coordinates from existing table in 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 ...
2
votes
2answers
3k 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
535 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
188 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
891 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
246 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
427 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
184 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
183 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 ...