I wrote: >> Generating an infinite list from a random generator "burns up" >> the generator, making it unusable for any further calculations.
Jake McArthur wrote: > That's what the split function is for. ^_^ Yes, that is a nice approach. I have been avoiding it due to the following comment in the docs for System.Random: "This is very useful in functional programs... but very little work has been done on statistically robust implementations of split ([System.Random#Burton, System.Random#Hellekalek] are the only examples we know of)." And my own experience has been that cases where I need split tend to be in a state monad anyway, where there isn't any real advantage to split. That said, looking around briefly, I came up with this paper by L'Ecuyer et al that does seem to describe a decent random generator with properties of split worked out: http://citeseer.ist.psu.edu/493863.html L'Ecuyer's implementations in C, C++ and Java are here: http://www.iro.umontreal.ca/~lecuyer/myftp/streams00/ If we had something like that in Haskell, I might use split more often. Regards, Yitz _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
