The subintervals are consecutive, and each inner bound signals where one interval ends and where the next begins, with the first and last elements of the vector denoting the limits of the entire interval of values the distribution can produce.
Each interval is assumed to be closed on its lower bound and open on its upper bound: [bi,bi+1).
The size of the vector is the number of intervals plus one.
A vector with the distribution subinterval bounds. result_type is a member type, defined as an alias of the first class template parameter (RealType).