h3ron 0.18.0

High-level rust API for H3
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53

//! # Hashing
//!
//! This crate uses `ahash` for its `HashMap` and `HashSets`. This hash hash shown in benchmarks to be
//! approx. 10% faster with H3 indexes than the standard `SipHash` used in rust. On the other hand it shows a higher
//! fluctuation in runtime during benchmarks. Interestingly the normally very fast
//! `rustc_hash` (uses `FxHash`) seems to be very slow with H3 cells and edges. Mostly noticed during
//! deserialization of graphs, but also during using the `pathfinding` crate which uses
//! `rustc_hash` internally. May be related to <https://github.com/rust-lang/rustc-hash/issues/14> and
//! the quadratic insertion cost issue described [here](https://accidentallyquadratic.tumblr.com/post/153545455987/rust-hash-iteration-reinsertion).
//!
//! `hashbrown` is used as it supports some APIs which are still unstable on `std::collections::HashMap`.
//!
use std::hash::Hash;

pub use ahash::RandomState;
pub use hashbrown;

pub use compactedcellvec::CompactedCellVec;
pub use compressed::{Decompressor, IndexBlock};
#[cfg(feature = "roaring")]
pub use treemap::H3Treemap;

use crate::{H3Cell, H3DirectedEdge, Index};

pub mod compactedcellvec;
pub mod compressed;
pub mod indexvec;
#[cfg(feature = "roaring")]
pub mod treemap;

/// generic trait to check if a index is contained in a collection
pub trait ContainsIndex<I: Index> {
    /// check if the given [`Index`] is contained
    fn contains_index(&self, index: &I) -> bool;
}

pub type HashMap<K, V> = hashbrown::HashMap<K, V, RandomState>;
pub type HashSet<V> = hashbrown::HashSet<V, RandomState>;
pub type H3EdgeMap<V> = HashMap<H3DirectedEdge, V>;
pub type H3CellMap<V> = HashMap<H3Cell, V>;
pub type H3CellSet = HashSet<H3Cell>;

impl<I: Index + Eq + Hash> ContainsIndex<I> for HashSet<I> {
    fn contains_index(&self, index: &I) -> bool {
        self.contains(index)
    }
}

impl<I: Index + Eq + Hash, V> ContainsIndex<I> for HashMap<I, V> {
    fn contains_index(&self, index: &I) -> bool {
        self.contains_key(index)
    }
}