I have a line layer in QGIS that I have digitized on the basis of a PNG file. This layer includes main lines and many secondary lines. I would like to remove these secondary lines automatically and not manually, as there are a lot of them. In most cases, these secondary lines only have one vertex and are then connected to the main line. Is there a way to remove the secondary lines? For example, by removing all end vertices of the vector?
One option would be to use an expression to select the features to be deleted (Select by Expression).
overlay_intersects will get the list of features intersecting, and array_length will get the count of these.
num_points will get the total number of points.
If the ratio of these is <=0.5 then it should meet your secondary point criterion (one intersecting point, and other point(s) not intersecting). Any main lines should fail this criterion.
array_length(overlay_intersects(@layer,@feature))/num_points(@geometry)<=0.5
Obviously this assumes that your segments are actually intersecting as the image indicates!
Shortest path (layer to point)but that doesn't work because I have multiple parallel lines and I want to keep these Lines.v.generalizeonly returns an empty result. I will try the approaches in your second suggestionSettings -> Data Sources, and select Copy Features asPlain Text, WKT Geometry