The function generates M intervals, whose endpoints are
are drawn uniformly without replacements from 1,2,..., n. This routine can be
used inside wbs function and is typically not called directly by the user.
Usage
random.intervals(n, M)
Arguments
n
a number of endpoints to choose from
M
a number of intervals to generate
Value
a M by 2 matrix with start (first column) and end (second column) points of an interval in each row