Expand description
Rusty permutation that supports no-std and compile-time checked size.
§Cargo features
To import this crate to your project,
[dependencies]
rusty-perm = "0.2"It has the following cargo features.
- std (default): enable the standard library.
- rand (default): enable random sampling of permutation.
To restrict the crate to no_std, you can disable the default features.
[dependencies]
rusty-perm = { version = "0.2", default-features = false }§Import this crate
To import members from this crate,
use rusty_perm::{prelude::*, PermD, PermS};Both PermD and PermS represent permutations, except that
PermS has an embedded compile-time size in type signature. The static size
prevents from applying permutation on arrays of wrong sizes in compile-time, and saves
some runtime overheads.
§Identity
The identity permutation can be constructed with static or dynamic size.
use rusty_perm::{PermD, PermS};
let perm1 = PermS::<10>::identity();
let perm2 = PermD::identity(10);§Build by sorting slices and arrays
It can extracts the permutation by sorting an array.
use rusty_perm::{prelude::*, PermS};
// `perm` is an operator that maps [9, 6, -1, 4] to [-1, 4, 6, 9].
let perm = PermS::from_sort(&[9, 6, -1, 4]);
// Apply same permutation on another array
let mut array = [1, 2, 3, 4];
perm.apply(&mut array);
assert_eq!(array, [3, 4, 2, 1]);You can sort with custom comparing or key function by from_sort_by, from_sort_by_key and from_sort_by_cached_key.
use rusty_perm::{prelude::*, PermS};
// `perm` is an operator that maps [9, 6, -1, 4] to [9, 6, 4, -1].
let perm = PermS::from_sort_by_key(&[9, 6, -1, 4], |val| -val);
// Apply same permutation on another array
let mut array = [1, 2, 3, 4];
perm.apply(&mut array);
assert_eq!(array, [1, 2, 4, 3]);§Build by indices
The permutation can be constructed by demonstrating the sorted indices.
use rusty_perm::{prelude::*, PermD};
let perm = PermD::from_indices([2, 0, 1]).unwrap();
let mut array = [-9, -5, 3];
perm.apply(&mut array);
assert_eq!(array, [3, -9, -5]);§Inverse and composition
The example demonstrates the inverse and composition of permutations.
use rusty_perm::{prelude::*, PermD, PermS};
// Construct the permutation, its inverse and compose them
let perm = PermS::from_indices([2, 0, 1]).unwrap();
let inverse = perm.inverse();
let composition = &inverse * &perm;
// Check that composition with its inverse is identity
assert_eq!(PermD::identity(3), composition);Modules§
Structs§
- Perm
- Generic permutation data structure.
Traits§
- Perm
Apply - The permutation operator on slice-like types.
- Perm
From Indices - An operator that builds a permutation from a list indexes.
- Perm
From Sorting - An operator that builds a permutation type by sorting slice-like types.
- Perm
Product - The permutation composition operator.
- Permutation
- An abstract representation of permutation data structure.
Type Aliases§
- Perm0
- Permutation type with static size 0.
- Perm1
- Permutation type with static size 1.
- Perm2
- Permutation type with static size 2.
- Perm4
- Permutation type with static size 4.
- Perm5
- Permutation type with static size 5.
- Perm6
- Permutation type with static size 6.
- Perm7
- Permutation type with static size 7.
- Perm8
- Permutation type with static size 8.
- Perm9
- Permutation type with static size 9.
- Perm10
- Permutation type with static size 10.
- Perm11
- Permutation type with static size 11.
- Perm12
- Permutation type with static size 12.
- Perm13
- Permutation type with static size 13.
- Perm14
- Permutation type with static size 14.
- Perm15
- Permutation type with static size 15.
- Perm16
- Permutation type with static size 16.
- Perm17
- Permutation type with static size 17.
- Perm18
- Permutation type with static size 18.
- Perm19
- Permutation type with static size 19.
- Perm20
- Permutation type with static size 20.
- Perm21
- Permutation type with static size 21.
- Perm22
- Permutation type with static size 22.
- Perm23
- Permutation type with static size 23.
- Perm24
- Permutation type with static size 24.
- Perm25
- Permutation type with static size 25.
- Perm26
- Permutation type with static size 26.
- Perm27
- Permutation type with static size 27.
- Perm28
- Permutation type with static size 28.
- Perm29
- Permutation type with static size 29.
- Perm30
- Permutation type with static size 30.
- Perm31
- Permutation type with static size 31.
- Perm32
- Permutation type with static size 32.
- PermD
- Permutation type with runtime size.
- PermS
- Permutation type with static size known in compile time.