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If you don't want to write your own code you can use the GDAL Python bindings to do that. Let's say this is your GPS point with lat and lon: from osgeo import ogr, osr # your gps earthquacke point gps_lat = 47.86 gps_lon = 12.66 gps_point = ogr.Geometry(ogr.wkbPoint) gps_point.AddPoint(gps_lon,gps_lat) So your earthquake happens somewhere in the Alps ...


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EPSG:24378 Kalianpur 1975 / India I should be the local CRS in the region you mentioned. The extent seems to fit to that: To get this picture using QGIS, create these text files: E N 73.4775 34.3629 and Easting Northing 3250193.00 1115573.00 3249214.00 1111220.00 Load each into QGIS as Delimited Text File, with blank as delimiter and setting CRS to ...


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the equation that you are pointing to seems to be correct. (degree + minutes/60 + seconds/3600). The error could come from a wrong datum. Data from a GPS are usually in WGS 84, but some GPS make an internal conversion into a local datum. Checking the datum is thus the first thing to do. Also note that ArcGIS is projecting on the fly, but it is not applyig ...


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Theres an item called Solmeta Geotagger Pro, which you might want to take a look at, im not sure about the price. http://www.solmeta.com/Product/show/id/14 We've used it, but had mixed results if you are not in the open, as the slightest interferences cause incorrect measurements. It is not usable in a car for example.


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This way it works: For Easting, subtract 108 000 000 from lng, and divide by 600 000 For Northing, subtract 54 000 000 from lat, and divide by 600 000: lng lat E N 177514245 34726053 115,857075 -32,123245 177513828 34726948 115,856380 -32,121753 177508930 34829424 115,848217 -31,950960 177508084 34829842 ...


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RTK is for real-time centimetre-level accuracy. I don't think that you need such a bazooka to locate trees in a farm (I assume that those trees are isolated if you talk about a farm and not a forest). Furthermore, RTK relies on signal emitted from a ground based station which might not be available in your area (especially if it is mountainous). On the ...


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You are correct. Precision is how close each of the data points are to each other and accuracy is how close to the target the data points are. Just be carful with how you take your data points. New GPS units use more than just the GPS locations now. So I would check each of the channels and see what data it is gathering and what data is inferred.


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With qualifications and suitably modified, this is correct: the standard deviation measures spread, which is inversely related to precision, while the vectors (not distances) to the reference points measure inaccuracy. Discussion With only five readings per location several problems will arise: The standard deviations of the coordinates will vary--by a ...


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There is no simple and accurate way to do it because ellipsoid. conversion to meters varies depending latitude. See : Length of a degree: where do the terms in this formula come from? one way to make it very simple (but not very accurate) is use table from http://en.wikipedia.org/wiki/Decimal_degrees. use 0.001 degrees and trigonometry to solve points


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For your first problem, make sure the point layer is loaded in WGS84. You can also use Add vector layer to load GPX files. If you want the points in another CRS, don't use SET CRS for layer. The right way is to save the data with Rightclick -> Save As ... and choose the wanted CRS and another file format like shapefile. GPX is always treated as WGS84.


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All this talk of "intersecting spheres" cannot possibly be true. Here's why. When you receive the signal from one satellite you know where it is because that information was transmitted in the message and also precisely at what time it was sent. In the GPS system all the atomic clocks are kept in sync via control signals from the ground to an accuracy of ...


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I know it's been a long time and you probably no longer care for the answer, but in case you (or someone coming in from a web search) cares, I'll attempt an answer. To quote some text from the NMEA 0183 (unofficial reference at http://www.catb.org/gpsd/NMEA.txt, in case the official one disappears) specification, The numbers 65-96 are reserved for ...


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You can use Point Distance (Analysis) tool to find the distance from each point to the nearest neighbor point. Use search distance of 500 m. The result is a table with distances between each point to its nearest neighbor point. Join the table back to your point feature class. (You need ArcGIS for Desktop Advanced (ArcInfo) license level for Point Distance ...


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You have a couple of options you could try. Firstly you could use the select by location to select all the points within a distance of the point you are interested in. This is probably only useful to if you are checking a handful of sites rather than your several thousand. Alternatively you can put a buffer around all of your points to start identifying ...


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I would suggest to set a tolerance around the position of the the points (roughly 10 m) then your merge the position when the distance is below the tolerance. Similarly, you can run a kernel along your track to find out the average position. The tricky part is to also account for time in order to avoid merging two parallel tracks. another solution is to ...


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In this case you might be more precise if you fine tune your points on a computer later. For example try to note the position of the point relatively to a tree or any other significant feature in the landscape. Anyway, even if you position your point perfectly at the right place, it is very likely that the user of your guide won't have a better GPS than ...


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I've done exactly the same thing for the same purposes - creating GIS-based rock climbing guides using GPS points taken with a mobile phone. I collected my points using an iPhone and the iGIS app. What I liked about iGIS was its ability to read/write directly to shapefiles, so you can get your attribute schema all setup outside of the app. Screenshot of ...


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This might be such an obvious answer that others haven't said it (or you already know it) but it seems worth saying: There are good value units (Garmin Etrex 20 or 30 for example) which can relatively easily be set up to use OSM vector data. With some skill I think that it is possible to adapt the renderings etc too (rather than simply going with what's ...



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