Function range_query

pub fn range_query<'a, DT, P, D, F>(
    data: DT,
    distance: F,
    epsilon: D,
) -> impl Fn(&P) -> IndexSet<P, BuildHasherDefault<FxHasher>>
where
    DT: IntoIterator<Item = &'a P> + Clone,
    P: Eq + Hash + Clone + 'a,
    D: PartialOrd,
    F: Fn(&P, &P) -> D,

Generates range_query function for dbscan.

Takes:

• data: iterable collection of points (the same data should be passed in dbscan).
• distance: function that should returns distance between 2 given points.
• epsilon: maximum distance between neighbors.