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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1answer
267 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 ...
2
votes
1answer
238 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
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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 ...
3
votes
1answer
1k 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
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1answer
265 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
406 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.
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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 ...
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3answers
3k 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
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1answer
2k 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
160 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
593 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
169 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
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3answers
696 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
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
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 ...
4
votes
3answers
6k 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
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2answers
953 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 ...
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1answer
333 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
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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
426 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
722 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
329 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
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1answer
222 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
4k 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
745 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
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0answers
141 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 ...
1
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1answer
1k 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
610 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
289 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
426 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
892 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
315 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
13k 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
412 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. ...
4
votes
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
1answer
355 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
2answers
530 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 ...
8
votes
4answers
3k 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 ...
14
votes
4answers
23k 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,
1
vote
1answer
278 views

Calulate distance between two points [closed]

If I have two coordinate points of (lat, lon), how would I calculate the distance between the two?
3
votes
3answers
554 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 ...
9
votes
3answers
1k 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 ...
2
votes
1answer
82 views

Latitude and Longitudes are replaced with zeros when importing excel 2007 worksheet into personal geodatabase

I am trying to import an Excel 2007 data set into a personal geodatabase so I can convert coordinate systems. The data set includes point locations in Decimal Degrees. When I import the Excel ...
3
votes
2answers
209 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 ...
6
votes
2answers
768 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 ...
0
votes
1answer
891 views

How to adjust the difference between the coordinate from OpenStreetMap and Google Maps

I have downloaded the OSM from OpenStreeMap that came with all nodes from the map and their respective coordinates. Now I have to plot a node (latitude and longitude) on Google Maps, but all ...
5
votes
2answers
2k 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 ...
1
vote
1answer
488 views

Retrieving XY from point graphics set in WPF network (arcgis 10.0)

I have a WPF application using ArcGIS 10. In the application I can set two point by clicking on map and calculate route between them. every time I click on the map, The application creates a ...