I have a table of observations along a line (Road), with a distance of each observation point from start or from the last observation. I am looking for a method to locate the points from the table using the distance field (From the start point of the road). The table has the distance parameters from the start, but no coordinates (Only for the road start).
How do I do this using QGIS?
Use Geoemtry Generator for visualization only or Geometry by Expression for actual geometries (see here for differences) with this expression, where you have to replace distances by the name of the layer and dist with those of the fieldname containing the distance values:
collect_geometries(
array_filter(
array_foreach(
aggregate( 'distances', 'array_agg',dist),
line_interpolate_point( $geometry, @element)
),
@element is not NULL
)
)
Points (red) created on the line at distances from the line's start point according to the values in the attribute field dist from layer distances:
Remark: Geometry by Expression returns a multipart geometry with all point in one feature. Run Multipart to single parts to get a separate feature for each point.
