These functions generate random points on a sphere using different rules.
The number of points to be simulated.
runifsphere generates uniformly-distributed random points on the
runifsphere.wrong generates random points which are uniformly
distributed in (longitude, latitude) coordinates.
These are not uniformly distributed on the sphere.
A data frame containing two columns of coordinates: the first column for longitude, the second column for latitude.
Adrian Baddeley and Tom Lawrence