Struct ValuatedMatroid 

pub struct ValuatedMatroid {
    pub matroid: Matroid,
    pub valuation: BTreeMap<BTreeSet<usize>, f64>,
}

A matroid with a valuation on its bases (tropical Plücker vector).

The valuation v: bases → R satisfies the tropical Plücker relations.

Fields

matroid: Matroid

Underlying matroid

valuation: BTreeMap<BTreeSet<usize>, f64>

Valuation: basis → value

Implementations

impl ValuatedMatroid

pub fn from_tropical_plucker( k: usize, n: usize, coords: &[f64], ) -> Result<Self, String>

Create a valuated matroid from tropical Plücker coordinates.

Contract

requires: coords.len() == C(n, k)
ensures: result satisfies tropical Plücker relations (approximately)

pub fn satisfies_tropical_plucker(&self) -> bool

Check if the valuation satisfies tropical Plücker relations.

The 3-term tropical Plücker relation states: for any (k-1)-subset S and elements a < b < c < d not in S, the minimum of {v(S∪{a,c}) + v(S∪{b,d}), v(S∪{a,d}) + v(S∪{b,c})} is attained at least twice (where v(S∪{a,b}) + v(S∪{c,d}) is included).

Trait Implementations

impl Clone for ValuatedMatroid

fn clone(&self) -> ValuatedMatroid

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ValuatedMatroid

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.