[SciPy-User] Volume of convex hulls from Delaunay triangulation

Pauli Virtanen pav@iki...
Sun Oct 14 08:58:52 CDT 2012


Eric Bruning <eric.bruning <at> gmail.com> writes:
> Are there any known edge or degenerate cases with the simplex volume
> calculation in scipy.spatial's test_qhull.py (1)? Applying this method
> to my dataset, some of the volumes are negative and some are positive,
> which might just be the 3D analogue of area with a different surface
> normal.

The formula needs to be divided by ndim! to get the volume, cf.,
http://en.wikipedia.org/wiki/Simplex#Geometric_properties

The volume is indeed oriented, and abs() gives the actual volume.

I don't see any significant numerical caveats in the intended
volume calculation using this approach.

-- 
Pauli Virtanen



More information about the SciPy-User mailing list