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3

You can specify a data-defined override using the button right next to the angle input In previous QGIS versions, this functionality was available through the data-defined properties button.


3

I have a solution that works. A LinearRing is also a LineString so use directly a LineString and you can project your points (using Shapely:Coordinate of the closest point on a line) line = LineString(list(polygon.exterior.coords)) pt1 = line.interpolate(line.project(point1)) pt2 = line.interpolate(line.project(point1)) Now we need to know on what ...


2

You should check out SFCGAL, which is a C++ wrapper library around CGAL with the aim of supporting ISO 19107:2013 and OGC Simple Features Access 1.2 for 3D operations. You can use it from a specialised version of PostGIS, here are the functions for PostGIS 2.1. Also, check out the existing functions that matches \df ST_3D*, which doesn't require SFCGAL. ...


2

The fact that the code snipped linked above uses FID = inFeat.id() shows that the tool is working on a random selection of the IDs, therefore this will not be "spatially random". The term is a little unclear to me so I'm not sure how they are different, but what is clear is that the tool appears to be operating on a random basis in terms of the ID table of ...


1

This may be a bit more work than you want to do, but if you edit the layers with advanced digitizing enabled, you can create a new feature starting at a point and as you move the mouse around to other points and positions the distance is displayed in the advanced digitizing panel. You can then copy down the ...


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In QGIS use the dissolve function from menu: Vector > Geoprocessing Tools > Dissolve... This will get you a new table with only the outer perimeter geometry.


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It turns out that one of the files had got corrupted. When I went into the layer folder, one of the file extensions was ending in [filename]_packed.dbf rather than just [filename].dbf I managed to resolve this simply by deleting '_packed' from the file name.


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Overwrite the defaults in L.Path with: L.Path.include({options: newDefaultStyle}); e.g.: L.Path.include({options: { color: '#dd8855', fillOpacity: 0.5 }});


1

From some quick searching it doesn't appear the Vector -> Research Tools -> Vector Grid, Geoalgorithms > Vector creation tools > Create Grid, or MMQGIS plugin allow for rotation in grid creation. The easiest thing to do would probably be create the grid and move/rotate it manually. Start by determining the length of one side of your square. ...


1

Well if you can remove vertex (nodes) in the qgis desktop GUI you can do it programmaticly too. So if I understood correctly you create lines from 2 points. Are they created as a new layer? If so you can just create each layer for points and the line. And then you simply remove the points layer with root.removeLayer(someLayer). If your line layer is not in a ...


1

In order to be able to use a Basic level license of ArcGIS for Desktop to perform intersections (or other polygon overlays like Union) between more than two input feature classes I would recommend performing them pair-wise i.e. for four input feature classes intersect the first two, then intersect the other two, before intersecting the preceding results. ...


1

I'd give PostGIS a try. E.g., if you have two tables b48 and b71 with buildings from 1948 and 1971 respectively (with fields "gid" as building identifier and "geom" as the building geometry), you could easily find the differences with something like: SELECT b48.gid gid48,b71.gid gid71,ST_Area(ST_Intersection(b48.geom,b71.geom))/ST_Area(b71.geom) ratio FROM ...


1

You will need some reference from the CSV file to a spatial table to map it. All you seem to have is a id and a pollutant value. If Rstudio made the concentration contour it might be able to export a local reference system for each cell in the raster map. Another go would be to georeference your concentration contour map in QGIS. Then you can use it as a ...



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