I have square polygons that follow the route of a boat. There is also a point layer with different measurements like salinity, temperature etc. Sometimes there is only 1 point inside the polygon, but sometimes more. In that case, I need to calculate the mean for different measurements inside the polygon, so as a result, I can create a new point layer with only 1 point per polygon (the mean - if there were several points, and keep the same data if there were only 1 point in a polygon).
I tried to use Join attributes by location (summary) tool, but I got all
NULL values for the mean values I wanted for different columns. The same result was from
v.vect.stats from GRASS.
Also if a point belongs to two polygons at the same time, I want it to be included in both.