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In theory, any GPS device should be able to decode ephemeris and almanac data from the raw GPS signal, without requiring a wireless connection. However, I know there are some Android devices that were engineered to supply this data only over a wireless connection. This is defined at the GPS chipset layer, and typically you can't find any documentation this ...


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I think Hausdorff distance may be what your looking for. It's basically a measure of how similar two geometries are. General steps to apply it to this problem: Find the closest point on the track to beginning and end of each planned segment. divide the track into segments between these sets of points. Calculate the Hausdorff distance between the planned ...


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from the above example, I suggest that you 1) create points along the green lines at a regular interval 2) get the perpendicular distance from those points to the blue line and, finally, 3) compute the average error based on those distances. Note that you could reject points that are too far (above a given tolerance for GPS worst precision) due to the ...


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Do you have ArcGIS? If so, you can follow these directions below and it will take about 5 minutes. Download US Counties from ESRI Follow ESRI's instruction at HowTo: Find the centroid of polygons using Calculate Geometry This results in a table of Latitude and Longitude attributes as well as points for the centers on your map.


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(This answer addresses the comments of John Barça’s comments… a little too large to put into the comments section). Again, I got this to work using PhoneGap, but I should perhaps clarify things a little bit. 1) I used PhoneGap Build instead of installing PhoneGap on my computer (glad to have a workmate who can give me this great kind of advice!). You will ...


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According to this page, the latitude and longitude values could be in (1) degrees, (2) degrees and decimal minutes, or (3) degrees, minutes, and decimal seconds. In your example, (2) is a decimal value and (3) is zero, so you have degrees, decimal minutes. So, you'll have to some checks on the three values to determine which format is being used.


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If you wish to use HTML5, you are probably better off using PhoneGap. PhoneGap abstracts away the significant differences between the hardware and APIs on different mobile platforms, iOS, Android, Windows, etc, allowing you to use Javascript, CSS and HTML to access the sensors, such as GPS. See the supported features/sensors grid. You cannot otherwise access ...


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Maybe you can find some hints and solutions in this blog posting by the developer of the OSM-based routing solution Graphhopper. His project with your aim is called Map Matching


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What you are after is a good map-matching algorithm. There are very few available off the self: see explanation and description on OSM. In case you're interested in simply using an API for that purpose, have a look at TrackMatching on my profile.


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So, it was because I hadn't specified that points should be stored in latitude and longitude when running osm2pgsql. The command I used successfully was osm2pgsql -c -l -s -d england_osm ~/Downloads/england-latest.osm.pbf


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The query looks good but if you want all ways which are partly in a bounding box you have to use the st_intersects function. If you want to show the error of your defined bounding box and you don't have any software you can put you bounding box in an ST_AsGeoJson function to get an geojson string as result. The easiest way to check your geometry is to ...


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I don't know that there's a single comprehensive history, but possibly the best place to search is the folks who created it - the US Military. Try a search for: gps history site:mil Some results that may be of interest: Timation and GPS Satellite History - Acronym heavy, detailed, describes the history of the science/engineering behind it. Global ...


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You can have a closer look at Miataru It seems to be an opensource and multi-platform solution, but I have not tried on my own, so please try to get special information from its website


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The following workflow is for QGIS and will give you the mean distance from the route for each transect in metres. I'm assuming the data will be using a projection in metres. Buffer your transects and route, for example, by 1m with Vector > Geoprocessing Tools > Buffer(s). You now have two polygon layers - the transects and the route. Give the route ...



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