[GRASS-user] vectors: how to find the gravitation centre of point data ?

[Hamish]

> If this is combined with a previous step to create
> individual CATs for the exclave areas while preserving the
> original CAT in another column, we can successfully apply
> v.to.db even while several areas share the same ID (having
> the centroids xy-coordinates for all exclave-area) _plus_
> having the coordinates for the super-centroid of all
> exclaves.


beware the "C" shape area where the center of gravity is outside of the area; centroids should always do a point-in-polygon test.


Hamish