yui-core

The foundational crate of the yui workspace: algebraic trait hierarchy, concrete numeric types, polynomials, linear combinations, and supporting algorithms / extension traits.

Layout

src/
├── abst/    — algebraic trait hierarchy: Ring, EucRing, Field, RMod, ...
├── conc/    — concrete instantiations: Ratio, FF, Sign, Poly, Lc, BitSeq
├── ext/     — extension traits: IteratorExt, RangeExt, IntoDigits, ...
├── algo/    — TopSort, UnionFind, KeyedUnionFind, rep_comb
└── util/    — formatting, data-dir resolution, thread-safe counter

Algebraic hierarchy

The traits in abst/ form the algebraic supertrait stack that everything else is generic over:

              MathType                  (basic shape + math_symbol())
                 │
           ┌─────┴─────┐
           ↓           ↓
         AddMon       Mon               (zero, +)        (one, ×)
           ↓           │
         AddGrp        │                (negation)
           └─────┬─────┘
                 ↓
               Ring     ──────►  RMod   (module over a ring R)
                 ↓
              EucRing                   (gcd, div_rem)
                 ↓
               Field                    (every nonzero invertible)

Arrows ↓ denote supertrait inheritance: Ring: AddGrp + Mon, EucRing: Ring, etc. RMod takes its scalar ring R: Ring as an associated type, not a supertrait.

A typical where-clause:

fn foo<R>(x: &R) -> R
where R: Ring, for<'x> &'x R: RingOps<R>
{ ... }

The for<'x> HRTB on the reference impl is required throughout; the auto_impl_ops crate derives the four Add/Mul reference variants from a single +=/*=.

Concrete types

conc/num/:

• IntType impls for i32 / i64 / i128 / BigInt.
• Ratio<T> — fractions over a Euclidean ring; Ratio<i64> and Ratio<BigInt> are the rationals.
• FF<p> — finite field 𝔽ₚ for prime p. For 𝔽₂, prefer the specialized FF2 (uses XOR/AND directly on a bool).
• QuadInt<I, D> — quadratic integers in ℤ[ω] for ω = (1+√D)/2 or √D; aliases GaussInt, EisenInt.
• Sign — the multiplicative group {±1}, with the GetSign trait.

conc/poly/:

• Poly<X, R> — univariate polynomial.
• LPoly<X, R> — univariate Laurent variant.
• Poly2, Poly3 (fixed arity), PolyN<X, R> (multivariate), plus their Laurent variants.

conc/lc/:

• Lc<X, R> — formal linear combination Σ rᵢxᵢ with keys X: LcKey and coefficients in R: Ring. Elements of the free R-module over the key set.

conc/misc/:

• bitseq::BitSeq<I> — packed sequence of bits over a word I, length up to I::BITS. Aliases BitSeq8, BitSeq16, BitSeq32, BitSeq64, BitSeq128 pin the width.

Quick example

use yui_core::num::Ratio;

let a = Ratio::new(1_i64, 2);
let b = Ratio::new(1_i64, 3);
assert_eq!((&a + &b).to_string(), "5/6");
assert_eq!((&a * &b).to_string(), "1/6");

Feature flags

• serde — Serialize/Deserialize for the concrete types.

License

This library is licensed under the MIT License.

This README was generated by Claude.