Hi everyone, Using a simulation, I have to find what are the probabilities that, in a square region, the convex hull is a triangle, using the "chull" function. However, I have a hard time with the chull function, i did not see many examples in which the chull function is used. I searched a long time on google, but I did not find nothing. So, if anyone can help, Thanks! _________________________________________________________________ Clavardez avec tout le groupe et rassemblez-les. [[alternative HTML version deleted]]
Isn't the single example enough in help(chull)? In your case I think you are finding the probability of length(chull(x)) == 3. Regards, Yihui -- Yihui Xie <xieyihui at gmail.com> Phone: +86-(0)10-82509086 Fax: +86-(0)10-82509086 Mobile: +86-15810805877 Homepage: http://www.yihui.name School of Statistics, Room 1037, Mingde Main Building, Renmin University of China, Beijing, 100872, China On Mon, Mar 9, 2009 at 11:29 AM, Alexandre Pratte <flyersgoaler at hotmail.com> wrote:> > Hi everyone, > > Using a simulation, I have to find what are the probabilities that, in a square region, the convex hull is a triangle, using the "chull" function. ?However, I have a hard time with the chull function, i did not see many examples in which the chull function is used. ?I searched a long time on google, but I did not find nothing. ?So, if anyone can help, > > Thanks! >
> Using a simulation, I have to find what are the probabilities that, > in a square region, the convex hull is a triangle, using the "chull" > function. However, I have a hard time with the chull function, i > did not see many examples in which the chull function is used. I > searched a long time on google, but I did not find nothing. So, if > anyone can help,The chull function returns the indexes of the points in the input that form the convex hull. Thus, to test whether or not the convex hull is a triangle, you simply test to see if its length is 3, i.e. length(chull(x)) == 3 If you need more information, you'll have to provide a reproducible example. Regards, Richie. Mathematical Sciences Unit HSL ------------------------------------------------------------------------ ATTENTION: This message contains privileged and confidential inform...{{dropped:20}}