I have a points layer with random points located along a route (polyline layer). I was wondering if there is a simple way to give a sequence number to each point in the order they show up along the route.

I am using QGIS 3.8, but I am very green and struggle with the lingo. I did install the LRS plugin hoping it might be a straight forward solution for me, but I can't make sense of it.

  • Are your points lie exactly on lines or they are located alongside the lines? What should be considered as a 'starting point' from which counting shall start? Is there any sort of relation between points and polylines, e.g. "ref_id"? – Taras Sep 26 '19 at 5:17

If your route (polyline) layer's name is Route1 which has an id field (fid), and the point layer is Bears like below example.

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Open the attribute table of the Bears (point) layer and start the Field Calculator.

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Create a new field (Dist) which shows the distance along the line by an expression:

line_locate_point(geometry:=geometry(get_feature('Route1','fid','1')), point:=$geometry)

Then start Add autoincremental field (Processing Toolbox > Vector table).

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Choose the distance field you have just calculated as Sort expression.

I think you should set the start value at 1, otherwise the first bear will get the number zero like below.

enter image description here

  • Sorry I have not been able to try this until now. This worked perfectly! Thank you Kazuhito. Thanks also to @taras for chiming in. – Nicci Oct 8 '19 at 2:23

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