Re: [R] Test for Random Points on a Sphere

2012-10-07 Thread 周果
Hi Lorenzo, Just a quick thought, the uniform probability density on a unit sphere is 1 / (4pi), what about binning those random points according to their directions and do a chi-square test? Regards, Guo On Sun, Oct 7, 2012 at 2:16 AM, wrote: > "Lorenzo Isella" writes: > > > Dear All, > > I

Re: [R] Test for Random Points on a Sphere

2012-10-06 Thread cberry
"Lorenzo Isella" writes: > 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 o

Re: [R] Test for Random Points on a Sphere

2012-10-05 Thread Nordlund, Dan (DSHS/RDA)
> -Original Message- > From: r-help-boun...@r-project.org [mailto:r-help-bounces@r- > project.org] On Behalf Of R. Michael Weylandt > Sent: Friday, October 05, 2012 11:17 AM > To: Lorenzo Isella > Cc: r-help@r-project.org > Subject: Re: [R] Test for Random Points on

Re: [R] Test for Random Points on a Sphere

2012-10-05 Thread R. Michael Weylandt
On Fri, Oct 5, 2012 at 5:39 PM, Lorenzo Isella 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 >

[R] Test for Random Points on a Sphere

2012-10-05 Thread Lorenzo Isella
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