3

I have a list of stations from which I would like to create a network of lines (the one created with the Delaunay triangulation would be fine) identified by a particular ID (for example, "AB" for the line from station A to station B) to which associate a list of measurements I already have (distance etc.).

I tried to use polygons to lines on the Delaunay triangulation layer, but the new lines vector has exactly the same table of it and I can't find a way to discriminate all the lines with a new ID...

This is the main table to which I would like to add all the new lines with the ID listed in the first column: enter image description here

"Fst" and "Matrice di distanza_Distance" are the measurements I need to associate to each line.

These are the tables for the Delaunay triangulation and the Polygons to lines layers, respectively: enter image description here

1

I am afraid doing all the task within a GIS software could involve rigorous workflow. (Honestly I do not know how to accomplish it).

May I suggest doing this in two steps, (1) In QGIS create a table of all combination of your stations and their distances, and then save it as a CSV file. (2) Open the output CSV file in a spreadsheet software (Excel, Calc) and create a Look-up table to complete your task.


Please find below only (1)st part; using QGIS.

  1. Create a point shapefile in which you have all your Stations. Make sure its attribute table has an identifier column (in this example, InputID).
  2. Virtual Layer (Go to menu Layer | Add Layer | Add/Edit Virtual Layer).

In the Virtual Layer window;

  1. [Import] your Stations layer.
  2. Fill the query input area:

Query is:

SELECT a.InputID AS INs, 
       b.InputID AS OUTs, 
       Round(st_distance(a.geometry, b.geometry),3) AS Dist_InOut
FROM Your_Stations_Layer  AS a
JOIN Your_Stations_Layer AS b
ON a.InputID <> b.InputID

enter image description here

Sorry I mistakenly entered FI to two points in the above picture, and the records 1 and 3 are different connections. :/

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