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Currently, I am working in QGIS to draw and plan grids. For different reasons I need to sort my pole layer (points) in the order that they run along with a cable layer (lines) with the same "cable_name". Each cable is divided into many features, sharing the same "cable_name". This is needed for voltage drop calculations. In other words, I have to sort the points from a certain point one after the other as they appear along the cable.

My current best idea on how to achieve this is to calculate the total length of the lines from a certain point, join the point layer, and sort according to distance.

enter image description here

The picture shows a grid with lines and poles. Between the poles are individual features (lines) They share the same "cable_name" so I can easily dissolve them back into one line. The trick is now to sort the Poles as they appear along each string. The star being my center point. In the yellow box for example I would like to automatically sort the poles like this: 211;213;214;427;431;215;216;218;...

I have tried the v.distance approach in GRASS but quickly abandoned that approach, as GRASS kept crashing and I am a newbie to GRASS anyways.

Any tips or different approaches? I am a bit stuck on my solving process.

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    Can you add a screenshot?
    – BERA
    Jun 29, 2020 at 18:20

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You could try to use Linear Referencing tools such as LRS Plugin for QGIS. With linear referencing you can add a measure to your polyline (cable). This measure works like kilometer marks along a street and is stored in a new "dimension" so each vertices get's x, y and M-values. Once you calibrated your route, so that the measure is rising from your "certain point" it is possible to query / calculate measures for any points on or next to your cable.

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  • Hi EikeMike, Thanks for your suggestion! I have tried the plugin and understand how this might work. Question: When I calibrate my route, where do I set the "certain point". Would it be at all possible to analyze my problem in a quick Screenshare session? I think it might be easier to follow your suggestion then.
    – Jesse
    Jun 30, 2020 at 14:56

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