Set operations, plus efficient sorting, ranking, searching, etc. The aim is to avoid moving data as much as possible. This is done by manipulating indices instead.
This crate defines Struct: Set, which wraps five kinds of sets: Empty, Unordered, Ordered, Indexed and Ranked, and methods acting upon them. These methods work on any generic vectors (or slices) of primitive end types <T>. Also, on any arbitrarily complex user end type, as long as the required traits PartialOrd and Copy, are implemented for it (by the user). It adds organisation and type safety to lower level methods from crate indxvec.
Insert into Cargo.toml file, under [dependencies]: sets = "^1"
The following 'use' declaration in source files makes available everything:
rust
use sets::{Set,MutSetOps};
Set<T>```rust /// The struct type for sets
pub struct Set
Clone and Display traits are implemented for Set and SType.
Default is derived, thus Default::default() generates an empty set.
SType specifies one of the five kinds of sets. It is dealt with by 'enumeration generics'.
```rust /// The five types of sets
pub enum SType { /// empty set #[default] Empty, /// unordered set Unordered, /// ordered set Ordered, /// indexed set Indexed, /// ranked set Ranked } ```
Initialisers are associated with the struct Set, hence to invoke them, the :: syntax is necessary, e.g. Set::new(..)
rust
/// all in one Initialiser: creates a new Set
/// of any self_type SType, from slice d, in asc order
pub fn new(set_type: SType, d: &[T], asc:bool) -> Self
There are also explicitly named convenience functions for all STypes:
new_empty, new_unordered, new_ordered, new_indexed, new_ranked. All the ordered types (i.e. ordered, indexed, ranked) take a bool argument specifying ascending or descending order.
rust
/// General converter -
/// converts s to a Set of the same type and order as self
/// (self only serves as a template).
pub fn to_same(&self, s:&Self) -> Self
Again, we have explicitly named converters:
to_unordered, to_ordered, to_indexed, to_ranked.
rust
let v = vec![1.,14.,2.,13.,3.,12.];
let setv = Set::new_unordered(&v);
println!("{}",setv); // Display setv
// ordered, ascending
println!("{}",setv.to_ordered(true));
// indexed, descending
println!("{}",setv.to_indexed(false));
It is highly recommended to read and run tests/tests.rs for more examples of usage. Use a single thread to run them. It may be a bit slower but it will write the results in the right order:
bash
cargo test --release -- --test-threads=1 --nocapture --color always
The output can be seen by clicking the last badge above and then the automated test logs therein.
Some of the general methods are more efficient for the ordered and indexed sets, rather than for the unordered sets. For example, member and search will automatically use the binary search. Union is like the classical merge with duplications across the sets removed. To remove repetitions within a set, use nonrepeat.
The STypes of the two operands of union, intersection and difference can be different. However, they are required to have the same end-type <T>. This is, perhaps, a useful type discipline.
Here 'm' in the methods' names stands for 'mutable'. They overwrite the mutable set to which they are applied with the result. Thus they are not functional but in the context of handling large vectors, they are often simpler and more efficient. At the price of destroying the previous contents of self, of course.
rust
/// Mutable methods for &mut Set<T>
pub trait MutSetOps<T> {
/// Makes a Set unordered
fn munordered(&mut self);
/// Makes a Set ordered
fn mordered(&mut self, quantify: &mut impl FnMut(&T) -> f64, asc:bool);
/// Makes any Set indexed
fn mindexed(&mut self, quantify: &mut impl FnMut(&T) -> f64, asc:bool);
/// Converts any Set type to ranked
fn mranked(&mut self,asc:bool);
/// General converter: s -> Set of the same type and order as self
fn msame(&mut self, s:&mut Self, quantify: &mut impl FnMut(&T) -> f64);
/// Deletes the first item from self
fn mdelete(&mut self, item:T) -> bool;
/// Deletes all occurrences of a matching item from self, returns their count
fn mdeleteall(&mut self, item:T) -> usize;
/// Inserts an item of the same end-type to self
fn minsert(&mut self, item:T);
/// reverses the vector of explicit sets and index of indexed sets
fn mreverse(&mut self);
/// Deletes all repetitions
fn mnonrepeat(&mut self);
/// Union of two sets of the same type
fn munion(&mut self, s: &Self);
/// Intersection of two sets of the same type
fn mintersection(&mut self, s: &Self);
/// Removing s from self (i.e. self-s)
fn mdifference(&mut self, s: &Self);
}
Version 1.2.0 - Updated to indxvec 1.4 and introduced compatible generalizations. No longer requiring users to globally implement From trait for all their types T but instead specify conversion closures on per-individual-use basis. This allows custom dynamic conversions. Beware that this breaks previous usage of mordered mindexed and msame methods of MutSetOps trait.
Version 1.1.4 - Updated dependency indxvec 1.4. Added automated github actions test.
Version 1.1.2 - Updated to indxvec 1.3.3. Pruned and simplified some code. Added deleteall to trait MutSetOps.
Version 1.1.1 - Eliminating unnecessary cloning. Updating to the latest dependency on indxvec 1.2.8.
Version 1.1.0 - Joined all four types of sets into one Struct Set. Simplified and generalised code by using enum generics.
Version 1.0.6 - Added mutable methods minsert and mdelete to MutSetOps, that insert or remove one specific item to/from any of the sets. Added tests of them to tests/tests.rs. Updated indxvec dependency to its version 1.2.4 or greater.
Version 1.0.5 - Documentation improvements.
Version 1.0.4 - nonrepeat now always returns an OrderedSet. Clarified settest.
Version 1.0.3 - updated to be compatible with indxvec version 1.2.1. Improved munion.
Version 1.0.2 - some changes to printing to reflect changes to indxvec.
Version 1.0.1 - some tidying up of code, no changes of functionality.
Version 1.0.0 - stable version with some minor improvements to README.md (this document). Updated to indxvec = "^1" and Rust edition 2021.