[Chimera-users] Question about Measure Volume and Area

[Thomas Goddard]

Hi Patrick,

   The calculation of volume enclosed in the triangulated surface is 
trivial.  I just choose any point (say the first vertex of the surface), 
then sum up the volumes of the tetrahedrons formed by that point and 
each triangle face making up the surface.  (Some of those tetrahedrons 
are inverted and have negative volume.)  This gives the exact volume 
enclosed in the surface which is defined by triangles.  One small catch 
is that I need to check that the surface has no holes since then the 
volume is not well-defined.  For a solvent excluded surface there will 
be no holes.

	Tom


Patrick Redmill wrote:
> Hey guys,
>    One more quick question. Is there a non-trivial calculation 
> associated with the surface enclosed volume? Or is it just a numerical 
> integration between the surfaces? If it's non-trivial, is there a good 
> ref for the algorithm? Thanks!
> 
> ~Patrick
>