On Fri, Oct 5, 2012 at 5:39 PM, Lorenzo Isella <lorenzo.ise...@gmail.com> wrote: > Dear All, > I implemented an algorithm for (uniform) random rotations. > In order to test it, I can apply it to a unit vector (0,0,1) in Cartesian > coordinates. > The result is supposed to be a set of random, uniformly distributed, points > on a sphere (not the point of the algorithm, but a way to test it). > This is what the points look like when I plot them, but other then > eyeballing them, can anyone suggest a test to ensure that I am really > generating uniform random points on a sphere? > Many thanks >
Gut says to divide the surface into n bits of equal area and see if the points appear uniformly in those using something chi-squared-ish, but I'm not aware of a canonical way to do so. Cheers, Michael > Lorenzo > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.