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1

Other way to measure this, it is using Qchainage (QGis plugin) to produce nodes equallly spaced from line. Then, you may use Distance to nearest hub (QGis plugin) to calculate distance among points.


2

A search with Google threw up these pages... http://blogs.esri.com/esri/arcgis/2011/09/06/creating-radial-flow-maps-with-arcgis/ http://blogs.esri.com/esri/apl/2012/09/12/generating-distributive-flow-maps-with-arcgis/ Someone has even created a tool that flows around country boundaries. ...


0

If you know how to use javascript and d3, then the spatialsankey d3 plugin might help. Here is an example application that does something similar to what you ask, though only to show flows in one direction.


0

The GRASS v.distance function should do the job, but it does not work through QGIS Processing. It can, however, be used through the QGIS GRASS plugin. Other easily available alternatives in QGIS are Distance matrix (under Vector-> Analysis Tools) and the NNJoin plugin.


2

You could try this in two different ways, either rotating your symbology (mark each location with a symbol that points at ), or rotating a label (each location has a static point symbol, and label rotated). Here's the Esri help page for each method: Rotate the label: Setting label rotation using a numeric field. I think this would work better for your ...


1

I found the answers provided here very helpful and came up with a refined version. So, here's another way to accomplish this task, but without having to alter the original table. SELECT t1.gid AS gid_1, t2.gid AS gid_2, ST_Distance(t1.geom, t2.geom) AS mindist FROM table t1, table t2 WHERE t1.gid != t2.gid AND ST_Distance(t1.geom, t2.geom) != 0 ORDER BY ...


2

A wiki article Centroid describes a few methods, including this one, which is probably the one used by most GIS tools: Centroid of polygon The centroid of a non-self-intersecting closed polygon, defined by n vertices (x0,y0), (x1,y1), ..., (xn−1,yn−1), is the point (Cx, Cy), where and where A is the polygon's signed area, ...


0

You can do the intersection in the field calculator if you use the Well Known Text representation of the lines. The 'intersects' operator evaluates to integers 1 or 0 as true or false, so you could run that operation with all lines on each point like so (this example has two lines): intersects( buffer( $geometry, 0.01), geomFromWKT( ...


1

A 32 bit Windows 7 Operating system can use at most 4 GB of RAM[1], combined for all activity on your machine. If your shapefile is very large and you also have many other programs running then you'll probably exceed 4 GB. So, to see which process uses up your memory you can open the Windows Task Manager (using ctrl-alt-delete) and then look at the ...


0

Get more system memory and use 64-bit R so it can utilize that memory. Your question has no information about the size of the file.


0

There is an arcInfo tool called generate near table to do that, but I guess that you don't have it the advanced licence if you ask the question. You can thus try the GME pointdistance tool. Here is a pure ArcGIS workaround, but it can be long. create a buffer of 50 km around each point then you can use "spatial join" with the "ONE_TO_MANY" option to ...


3

The following code is not polished but should work to create the same output table as the Point Distance tool but requires ArcGIS 10.1 (or later) for Desktop and only a Basic level license: import arcpy,math # Set variables for input point feature classes and output table ptFC1 = "C:/temp/test.gdb/PointFC1" ptFC2 = "C:/temp/test.gdb/PointFC2" outGDB = ...


1

This is by far not the best solution so hopefully others will post more efficient answers. Take your buffer layer of your points and run the Polygon-line intersection tool from SAGA (I used this from the Processing Toolbox). Your polygon buffers will now be split into segments depending on the number of lines which intersect it. So visually, you can see ...


3

Since you are building these in C#, the best way is probably to use the SQLGeography/SQLGeometry builder classes. These can be accessed from the Microsoft.SqlServer.Types library. Some examples of it's use are here. Since you are using GPS points, they are likely to be Lat/Lons. In that case I would use Geography datatype rather than Geometry. If you ...


0

for full control on extending lines, another possibility (besides the topology tools) is to create the line segments that fill the gaps and merge them with your lines based on some common attributes (using dissolve). So: 1) create the end points of the lines (feature vertices to point) 2) get the closest point (spatial join) 3) create the line segment (XY ...


1

When you create profile lines and use the Profile Graph tool , the tool creates points along the line for you and saves them in the same location as your MXD's default Geodatabase in a folder called ProfileGraph Data.


1

An option to normalize lidar clouds (and keep it as a point cloud) is Fusion. One will need the command line ClipData together with the switches dtm:file, which is the bare-earth model (DTM) + height. ClipData description says: ...When used in conjunction with a bare-earth surface model, this logic allows for sampling a range of heights above ground ...


1

Got it! line_center = [] featuresC = Center.getFeatures() for elem in featuresC: xy1 = elem.geometry().asPoint() center = QgsPoint(xy1) line_center.append(center) print line_center line_ends = [] featuresO = Outer.getFeatures() for elem in featuresO: xy2 = elem.geometry().asPoint() ends = ...


1

Answer came from http://forums.arcgis.com/threads/35323-ArcPy-amp-SelectLayerByLocation-Performance?p=119047#post119047 Thanks Jason Scheirer for some more concise code: SelectLayerByLocation(in_layer=arcpy.PointGeometry(arcpy.Point(x, y)), select_features="mylayer") And especially to Chris Snyder for a performance tip: A speedier work around might be ...


-2

Fusion LiDAR can do that, try download. User manual is simple and you can process lidar files via command line. http://forsys.cfr.washington.edu/fusion/fusionlatest.html edit: FUSION Manual: http://forsys.cfr.washington.edu/fusion/FUSION_manual.pdf try to search it using "normalize". You can create bare earth file using GroundFilter.


3

This is the exact problem that I am currently working on for my own research. As a result I have been working on a plugin tool for the open-source GIS Whitebox Geospatial Analysis Tools, called 'Isolate Ground Points'. It will take an input LAS file or point-type shapefile and output only the ground points in a multipoint-type shapefile. It turns out that ...



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