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With your VRT file GDAL tries to find layers "temperature" and "elevation" from the target databases. Either use the original layer names in VRT in OGRVRTLayer name: "rice_temp" and "rice_elev", of rename them with SrcLayer <OGRVRTDataSource> <OGRVRTLayer name="temperature"> <SrcDataSource>rice_temperature.sqlite</SrcDataSource> ...


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The solution in terms of geodesics is given in Section 8 of Algorithms for geodesics. This uses the ellipsoidal gnomonic projection to convert the problem to an equivalent planar problem. An implementation of the solution in C++ is given here. GeographicLib includes the necessary underlying geodesic routines in both C# and Java.


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This is a much simpler method.. UPDATE lines SET GEOM = ST_LineMerge(ST_Difference(GEOM,(SELECT ST_Union(ST_Boundary(GEOM)) FROM polys WHERE ST_Intersects(GEOM,lines.GEOM) = 1))) WHERE (SELECT geometry FROM polys WHERE ...


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if you use arcPy, create 2 rasters (need both to have same shape), new_raster and old_raster. Assume a value of zero is non-wetland and one is wetland in arcPy, convert both new_raster and old_raster to numpy arrays and: in_new_but_not_in_old = np.ones(new_raster.shape) * -9999 in_old_but_not_in_new = np.ones(new_raster.shape) * -9999 ...


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Assuming that you are dealing with geographic coordinates and geographic (true north) bearings, you have a couple of options: Project the situation onto the plane, solve using the simple planar coordinates method, and reverse project back to the spheroid. Perform geodetic or spherical geometry calculations. If your distances are not too great and your ...


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Assuming that we're dealing with the planar coordinate case (that is not actually what the OP suggested, but I offer this as a better answer to the one given so far – and so far, accepted, by the OP – for the planar case), it helps to first determine the direction cosines from the two clockwise bearings, βAC and βBC, from known points A ...


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Select by location all street lines that cross the boundary of your polygon. Use Feature Vertices to Points (requires an Advanced license) on the selected lines with the BOTH_ENDS option. Since line direction isn't guaranteed to be consistent in crossing your polygon boundary, you need both ends of the street line. Select by location all of the created ...


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First, you need to import the points, and make sure they have the same coordinate system. Then you can use intersect to find out for each point in what polygon it is located. See this topic also. Intersection between points and polygons in QGis


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This requires a few steps; 1. Transform your CSV to a shapefile using the add delimited layer Here Then merge your point layer to the polygon layer using spatial location :see here Now each point has its polygon attributes.


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Sorry, but the layers are not in the same CRS. The Catchments is in an Albers Equal area projection (units-meters) and the other two are in Haartebeesthoek94, with degree as units. So your area calculations are in square degrees. If you reproject the transmissivity and intersect polygons to Albers Eq Area (with the "Save As..." option in QGIS) then ...



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