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you can't really convert convert distances in degrees into meters as the size of a degree varies as you approach the poles. convert your locations into a projected coordinate system, then calculate your distances.


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Yes, it is called GeoNames (which you have a geonames tag for) although I cannot guarantee that it has every town in the world: A daily GeoNames database dump can be downloaded in the form of a large worldwide text file (allCountries.zip). Additional country files are available for convenience. You find the files on our download server. Read the ...


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Open up the Attribute Table. Turn on editing for the layer. Using the field calculator, calculate a new field with the following info: Name: X Type: Decimal Number (real) Width: 12 Precision:2 For your expression you want: $x Repeat for Y.


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i believe this may be an answer https://www.census.gov/geo/reference/centersofpop/animatedmean2010.html http://www.esri.com/news/arcuser/0311/population-drift.html plus this is a really interesting article on the math behind finding the mean center - http://www.ams.org/samplings/feature-column/fcarc-population-center long story short: somewhere in ...


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The coordinates must be in the same crs as the layer the diagrams are attached to. Could this be your issue?


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as Bernd V suggests, it might be easier to just add the appropriate x and y offsets in excel. another possibility is to use the Affine Transform plugin (when installed, it's under Vector > Geoprocessing Tools > Affine Transform) You'd want to select all points except the O point - unless it's (0,0), in which case you should include it too. Settings would ...


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Your transformation omits the offset between the Bessel and the WGS84 Ellipsoid. The full WKT would be: PROJCS["DHDN / 3-degree Gauss-Kruger zone 3", GEOGCS["DHDN", DATUM["Deutsches_Hauptdreiecksnetz", SPHEROID["Bessel 1841",6377397.155,299.1528128, AUTHORITY["EPSG","7004"]], ...


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This site will calculate 3D GPS positions very accurately. http://www.ngs.noaa.gov/cgi-bin/Inv_Fwd/invers3d.prl I couldnt tell if you were just asking how to calculate a couple points or how to automate the process. To automate i would just make a CURL script to hit this site with your point data.


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A point inside a polygon canvas = qgis.utils.iface.mapCanvas() aLayer = canvas.layer(0) # or code to select the layer of interest for f in aLayer.getFeatures(): geom = f.geometry() p = geom.pointOnSurface() print p.asPoint() Get Inner Rings canvas = qgis.utils.iface.mapCanvas() aLayer = canvas.layer(0) # or code to select the layer of ...


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Other users might be interested to know that I have managed to solve this. Rather than extracting the points directly, I used gIntersection in the rgeos package to truncate the lines to within the polygon, and then extracted the outer point. # Cut radial lines at polygon edge Centre_edge_lines <- gIntersection(Radial_spLines, Hull_poly, byid=T) # ...


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since the square if this image is slightly tilted, I am quite sure that this GeoTIFF is already map projected/georeferenced. Check the properties (e.g. QGIS /ArcGIS) to see which map projection it is. Actually, if you use gdal_warp on this Geotiff indicating your wanted output projection, it will probably read the existing map projection and reproject it ...


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You can use QGIS' quadrant placement specifier determined from the line's azimuth to place a better label. The quadrant specifies 8 positions around a point: [ 0=Above Left | 1=Above | 2=Above Right | 3=Left | 4=Over | 5=Right | 6=Below Left | 7=Below | 8=Below Right ] Here's an example around Null Island, creating a table and two views. ...


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okay.. as it's in map units this should be fairly straight-forward, within limitations. You already know the height of the label. If it was in points it would be scale-dependant. This assumes a fixed label size, so how well this works depends on how uniform your labels are, and whether or not you use a proportional or fixed-width font (fixed width is easier ...


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One way to do it is with the plugin "numerical vertex edit"(you can find it in the plugins repostory). There you can edit nodes by clicking on them and then changing their coordinates. The original coordinate is displayed in the edit-window, you can now copy them. Though I'm sure there are more elegant ways, it should do the trick.


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Why Using One Fixed Projection Will Not Work For a projection to be of any use at all for distance-related queries, it and its inverse should be continuous almost everywhere. Consider, then, what happens when you pick one point--any point--and start to draw on the map a collection of routes that emanate from that point and move straight away from it, in ...


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A very simple brute force approach: take the first points coordinates and convert them from ISN93 / Lambert 1993 to WGS84 degrees using cs2cs in the OSGEO4W shell cs2cs +init=epsg:3057 +to +init=epsg:4326 -f "%%.8f" <ISN93.txt >WGS84.txt build a local omerc CRS on that point, with the "local coordinates" as false Easting and Northing convert the ...


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You can create a custom CRS with these parameters: +proj=omerc +lat_0= -22.5 +lonc=25.09 +alpha=0.910238 +k=0.99977264 +x_0=0 +y_0=0 +gamma=0 +a=6378249.145 +b=6356514.966398753 +towgs84=-143,-90,-294,0,0,0,0 +no_defs +to_meter=10000 And you get the 10km-grid as described: I took the old ARC 1950 datum from EPSG:4209 as base, which was common in ...



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