Re: [OctDev] convhulln options.

[Pedro T. <pt...@te...>]

El Viernes, 19 de Diciembre de 2003 06:31, a Paul Kienzle  se le ocurri=F3 =
decir=20
lo siguiente:
> > 	- A polyhedron is just an ordered list of facets.
> > 	- A facet should contain:
> > 		- id number
> > 		- normals and offset (hyperplane supporting the facet)
> > 		- area
> > 		- set of vertices (n if simplicial, >n if non-simplicial)
> > 		- set of neighbours (again n  if simplicial...). Here's the need for
> > the id.
> > 		- set of ridges. (?)
>
> Maybe you want a structure array?
>
> 	x(id).normal =3D <normal>
> 	x(id).offset =3D <offset>
> 	x(id).area =3D <area>
> 	x(id).vertices =3D [v1,...,vn]
> 	x(id).neighbors =3D [id1,...,idn]
> 	x(id).ridges =3D <?>
>
> My only question is, are there relevant vector operations you want to
> do on the returned information?  Or do you need a for loop to process
> each id?  Since the octave interpreter is slow, I prefer to avoid for
> loops
> as much as possible.

Let me give you some ideas of what I'm doing. My hull belongs to an economi=
c=20
simulation model. Each facet has an economic interpretation in terms of=20
prices of different inputs. I do perform computations on every facet to get=
 a=20
set of points that will give me the shape of a demand function. So... I do=
=20
loop around all facets. I also have to study the equilibrium conditions=20
around the "optimal" facet and that's where the neighbors set becomes=20
specially important (neighbours for those of us who learnt english with a B=
BC=20
method ;) ).

Regards,
Pedro