If a cycle is wasted, Knuth gets quite irate Tangentially, I believe the topic of generating random points inside the unit ball is covered in vol 2 of TAOCP, w

If a cycle is wasted, Knuth gets quite irate Tangentially, I believe the topic of generating random points inside the unit ball is covered in vol 2 of TAOCP, with all the math you could wish for to justify the different methods.