type 'a t
a compiled finite discrete probability distribution that supports constant time sampling
val create : ('a * float) list -> 'a t
create dist compiles a discrete probability distribution into a form supporting constant-time sampling. The running time is O(N) where N = List.length dist. dist may be either a probability distribution (all floats are non-negative and sum to 1) or, more generally, a histogram in which frequencies are interpreted as probabilities.
val sample : ?state:Core.Std.Random.State.t -> 'a t -> 'a
randomly sample the distribution in constant time