Returns a set (list) of the increasing sets (integer vectors) of the input
vector v, in the sense that the first set contains the first element
of v, the second set the first and second elements of v, and so
on.
closest_subsets(v)An integer vector. Meant to represent the \(k\) nearest neighbors of a location, the first element being the integer identifier of the location itself.
A list of the same length as the input. The first element of the list is v[1], the second is sort(v[1:2]), the third sort(v[1:3]), and so on.