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5

You could try the Identity tool, using your line features as the input, and polygons as the identity features: "When the Input Features are lines and the Identity Features are polygons, and the Keep relationships parameter is checked (relationship set to KEEP_RELATIONSHIPS), the output line feature class will have two additional fields, LEFT_poly and ...


4

Update you roads direction using a formula something like if (45 <= (360 + math.atan2((!Shape.lastpoint.X! - !Shape.firstpoint.X!),(!Shape.lastpoint.Y! - !Shape.firstpoint.Y!)) * (180 / math.pi)) % 360 % 180) < 135): dir = 'W-E' else: dir = 'N-S' Then for each direction group number them in order using the first opposite ordinate to sort. ...


4

I think that "node centrality" concepts, in the graph theoretic literature, may be helpful. Here is an introduction to centrality measures in graphs.


3

Without an Advanced level license of ArcGIS for Desktop your best alternative may be to use ArcPy and Geometry objects. Upon seeing the Comment from @Michael Miles-Stimson I looked in the ArcGIS 10.2 Online Help and found that the Polyline object has a queryPointAndDistance method which: Finds the point on the polyline nearest to the in_point and the ...


3

That's a known issue of QGIS 2.2 but it should be fixed in the dev version and will be in 2.4. See http://hub.qgis.org/issues/9780


2

You do not specify which GIS system you wish to implement your analyses so you could investigate the sDNA which can be run in ArcGIS, python or AutoCAD.


2

Apologies if I misunderstood your question but perhaps you could create a new attribute column and calculate the length of each feature from there using: $length Hopefully others will help if I am indeed mistaken.


1

Here is a decent start to what you're asking. It can be more accurate if you somehow gathered the "mean direction" of all the vertices and used that to determine the azimuth for a given road segment. Also, this uses an arcpy.Sort_management function that sorts the feature table spatially starting, in this case, with a particular corner of the data (like "LR" ...


1

First thing first is clean up the data. 1) Use the UNSPLIT LINE tool with the dissolve field set to the street names. 2) Use the 'Plannerize tool' on the output at step 1 to create segments between each crossing 3) Used the 'intersect tool' to create points at each intersection. (Join Attributes set to FID_Only and the output type should be set to ...


1

I don't consider this a complete solution as it relies on non-out-of-the-box tools and isn't fully tested. It also may require an Advanced license. For now I am removing the comments I made linking to questions with methods using the start and end nodes of the lines, as after some testing I'm not sure how to apply that to this problem (while at the same time ...


1

That's a very nice use case for Linear Referencing tools. Have a look at my answer to this post: QGIS Linear Referencing. There I explain the capabilities of the QGIS LRS plugin. That should help you get started.


1

Right-click on your length field -> statistics -> look at the SUM field


1

EDIT : The default output of line density is in kilometer per square kilometer. So the output of the tool is already what you are looking for (you don't need to divide it again by the size of the circle, this is done automatically). Note that the vector-based approach from @Anggik will be more precise, however you will not have overlapping window analysis.


1

in my point of view, you should decide your unit area (it could be county boundary or certain grid). after that, do some geoprocessing to divide roads in each unit area. Then you calculate each of roads length in each unit area and divide with the hectarage (or km2).


1

I don't know what could be the difference between console and plugin, I think it should to work either way. Also you try to replace layer.commitChanges() (which makes not sense there) with layer.triggerRepaint() and look if that helps (note it is not necessary to call mapCanvas.refresh()). You can also use custom properties for the layer to enable labeling, ...


1

You have to distinguish between the Openstreetmap database and the extracts that are based on it. The website shows the current content of the database. With the link "Download XML" you can download the xml, and import it into QGIS using the OpenStreetMap plugin or "Add Vector Layer". The pbf files from Geofabrik offer you the same database content, cut to ...


1

Metadata is data about data - the coordinate system of a layer, what the allowable attribute values are, or what a given attribute is/means. In a shapefile (which is a database) what you're asking about is an attribute. However in the OSM data this information is stored as tags because it is xml (Extensible Markup Language) document and not a database. See ...


1

For advanced editing, I suggest to switch over to the editor JOSM. In JOSM, the way gets arrows in the direction while the way is in editing mode.


1

Softree Technical Systems has been working with the University of British Columbia's Mathematics Department on vertical alignment and earthwork optimization technologies. See: http://www.publicaffairs.ubc.ca/2012/12/18/revolutionizing-road-design/ Please refer to our website http://softreeoptimal.com/ for further details or send me an email at ...


1

While there is some degree of convergence happening between GIS and civil engineering CAD tools, you are probably much better off with the latter type of, much more specialized, tool. Some examples of suitable civil engineering CAD tools: Softree's RoadEng is very good (I worked on it briefly) and relatively low-cost. Autodesk's (AutoCAD) Civil 3D is ...


1

Ok a lot of questions, so I will start with a general hint: What you are looking for is just a 'routing graph' for a geodata set (here: OSM). As you say this graph needs to fullfil certain properties (as connectivitiy, level of detail, ...) but IMHO your cell approach sounds a bit complicated. There are existing solutions to turn OSM raw data into graph ...


1

Very late reply but I posted a similar answer not long ago. You can download .csv file which contains roads of GB (not UK unfortunately but still might be useful) with the length measured in miles: http://data.dft.gov.uk/gb-traffic-matrix/Traffic-major-roads-miles.csv It also contains coordinate data for it to be immediately imported into various GIS ...



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