R help - Jul 2008 - estimating volume from xyz points

Dear all,

I have several sets of x-y-z points and I need to estimate the volume that
encompass all my points.
Recently I got some adivice to show the "convex hull" of my points
using
geometry package (see code below).
But now I need to calculate the volume of my set of points.
Any advice are wellcome.

Thanks in advance

Miltinho Astronauta
Brazil
-----

require(geometry)
library(rgl)


x<-rnorm(100)
k<-runif(100)*20+5
y<-rnorm(100)
z<-sin(x)+cos(y)^2


my.data.3d<-data.frame(cbind(x,y,z))

my.data.3d = sqrt(3) * my.data.3d / drop(sqrt((my.data.3d^2) %*% rep(1,3)))

data.ts.surf = t( convhulln(my.data.3d,"QJ") ) # see the qhull
documentations for the options
## Not run:
rgl.triangles(my.data.3d[data.ts.surf,1],my.data.3d[data.ts.surf,2],my.data.3d[data.ts.surf,3],col="blue",alpha=.2)
for(i in 1:(8*360)) rgl.viewpoint(i/8)

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On Sat, Jul 19, 2008 at 5:21 PM, milton ruser <milton.ruser at gmail.com>
wrote:
> Dear all,
>
> I have several sets of x-y-z points and I need to estimate the volume that
> encompass all my points.
> Recently I got some adivice to show the "convex hull" of my
points using
> geometry package (see code below).
> But now I need to calculate the volume of my set of points.
?convhulln
also in geometry package.