5

For an examination of a local power grid, I need to mark the transformation stations (substation) by simply create a point for each station.

What I want to do is that QGIS creates a point at the end of a line automatically.

How can I get there?

example

6

Tested on QGIS 2.18 and QGIS 3.4

I can suggest using a "Virtual Layer" through Layer > Add Layer > Add/Edit Virtual Layer...

Let's assume there is a polyline layer called "polylines" (blue lines).

input

With the following Query, it is possible to create a point at the end of each line.

SELECT st_endpoint(geometry), *
FROM "polylines"

The output point layer (yellow) with its attribute table will look like

output

Mind the difference between ST_EndPoint and ST_StartPoint. Basically, what @TeddyTedTed meant by Which one you need will depend on the direction of the line.

Additionally, I may suggest using Python code from this article. Achieved from @Joseph's answer

line_layer = qgis.utils.iface.activeLayer()
feat = QgsFeature()

point_layer = QgsVectorLayer("Point?crs=epsg:31469", "point", "memory")
pr = point_layer.dataProvider()

for feature in line_layer.getFeatures():
    geom = feature.geometry().asPolyline()
    end_point = QgsPoint(geom[-1])
    feat.setGeometry(QgsGeometry.fromPoint(end_point))
    pr.addFeatures([feat])

QgsMapLayerRegistry.instance().addMapLayer(point_layer)
9

In the Processing Toolbox use the Extract Specific Vertices tool, for the Vertex indices use 0 for the first vertex and -1 for the last vertex. Which one you need will depend on the direction of the line.

EDIT: Apologies, I didn't read your question properly, you said automatically. If it's just for display purposed you could use a geometry generator symbology to show a point at the end of the line using end_point($geometry) as the expression. If you need to create an actual data point automatically every time a line is created then I'm not sure how to do that.

0

A simple solution could be:

Using Vector ‣ Geometry Tools ‣ Extract verticas. Afterwards simply delete all points but thoose which were generated at the end and beginning.

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