[Qgis-user] what is plotted

[M.E.Dodd]

If you have a map and you want to plot dots on it, each dot representing some quantity then what happens if you have several dots at exactly the same location i.e. the coordinates are identical.  Some possibilities are (a) just show the 'last' dot assuming qgis plots the dots one after another in order down the .csv file, (b) average the data then plot the average value at those coordinates, (c) something else, am sure there are other possibilities.  Am sure I have used gis systems in the past where both a and b have happened and its been difficult to tell what is going on.
In my instance an mean value at each location is probably the most appropriate.


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