aggregate

differential_dataflow::algorithms::prefix_sum

Function aggregate 

Source 
pub fn aggregate<G, K, D, F>(
    collection: Collection<G, ((usize, K), D)>,
    combine: F,
) -> Collection<G, ((usize, usize, K), D)>
where
    G: Scope<Timestamp: Lattice>,
    K: ExchangeData + Hash,
    D: ExchangeData + Hash,
    F: Fn(&K, &D, &D) -> D + 'static,
Expand description

Accumulate data in collection into all powers-of-two intervals containing them.