[R] How to generate the random numbers uniformly distributed on the unit disc?

[Peter Dalgaard]

"S.Q. WEN" <randsnews at gmail.com> writes:

> Hi,
> I want to get  random number which is uniformly distributed  on the unit
> disc.
> How can I do that with R?

Most easily, although perhaps not most efficiently, by using spherical
coordinates:

 N <- 10000
 r <- sqrt(runif(N))
 theta <- runif(N,0,2*pi)
 x <- r*cos(theta)
 y <- r*sin(theta)
 plot(x,y,pch=".")




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   O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
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