Nice to see this!  Thanks, John and Arvydas.
In the reference implementation of poisson distribution, it uses the same algorithm as I used in Gauche,
notably Knuth's in make-poisson/small and Atkinson's in make-possion/large.  I think it is helpful
to attach reference to them (the reference is in the comment of Gauche's code) in case future readers
wonder where these magic numbers came from.

On Mon, May 4, 2020 at 8:22 AM Arthur A. Gleckler <> wrote:

Scheme Request for Implementation 194,
"Random data generators,"
by Shiro Kawai (design), Arvydas Silanskas (implementation), John Cowan (editor and shepherd),
is now available for discussion.

Its draft and an archive of the ongoing discussion are available at

You can join the discussion of the draft by filling out the subscription form on that page.

You can contribute a message to the discussion by sending it to

Here's the abstract:

This SRFI defines a set of SRFI 158 generators and generator makers that yield random data of specific ranges and distributions.  It is intended to be implemented on top of SRFI 27, which provides the underlying source of random integers and floats.


SRFI Editor