On 10/28/07, Ivan Raikov <[EMAIL PROTECTED]> wrote: > > Hello, > > Does the random-mtzig egg do what you need?
It looks better, because you just seed the state as you please and then consistently pass the state. This means I can have one RNG that uses the same seed across interpreter invocations and another that is truly random. I dont know why things like SRFI-27 get ratified and have the inconsistency that Kon discusses in the "Issues" section of his docs: http://www.call-with-current-continuation.org/eggs/srfi-27.html With your mtzig library, I see how to create a uniformly distributed real from (0,1) but I do not see how to create a uniformly distributed integer from [0,n) where n is some number not necessarily the largest on the machine. Also, i do not understand why you did not pass in the created state in your example at the end: csi> (require-extension random-mtzig) csi> (random-mtzig:init! 24) csi> (random-mtzig:f64vector-randu! 20) The docs say that N * state (which I assume is a 2-tuple of an integer and the previously created state) is passed to that function. In fact, the docs are confusing because the type signatures imply that the functions take a state, but then the example at the bottom does not supply a state to random-mtzig:f64vector-randu! Compare these signatures: procedure: random-mtzig:init :: [SEED] -> STATE procedure: random-mtzig:random! :: STATE -> INTEGER In the first procedure SEED is an optional argument, in the second STATE is not indicated as optional. It must be supplied. > It can be seeded from > /dev/urandom, or with a constant supplied by the user, and you could > have multiple seed states that are passed to the random number > generating routines in the egg. I can also add some convenience > functions, if they would fit your needs better. Based on your API, here is what I would be aiming for: (define *fixed-seed* (expt 7 5)) (define fixed-state (random-mtzig:init *fixed-seed*)) (define (roll-fixed n) (if (zero? n) (random-mtzig:randu! fixed-state) (random-mtzig:random-from-zero-to-n n fixed-state) ; [0,n) )) (define random-state (random-mtzig:init) (define (roll-random n) (if (zero? n) (random-mtzig:randu! random-state) (random-mtzig:random-from-zero-to-n n random-state) ; [0,n) )) _______________________________________________ Chicken-users mailing list Chicken-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/chicken-users
