Struct JeroslowWangTwoSided 

pub struct JeroslowWangTwoSided { /* private fields */ }

Implements a two-sided version of the Jeroslow-Wang heuristic.

This heuristic first selects a variable based on the sum of JW scores for its positive and negative literals (score(v) = JW(v) + JW(-v)). Once a variable is chosen, it picks the polarity (positive or negative) that has the higher individual JW score. If scores are equal, polarity is chosen randomly.

Similar to the one-sided version, there’s a small chance (10%) that the final chosen literal’s polarity will be flipped.

Trait Implementations

impl Clone for JeroslowWangTwoSided

fn clone(&self) -> JeroslowWangTwoSided

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for JeroslowWangTwoSided

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

Formats the value using the given formatter.

impl Default for JeroslowWangTwoSided

fn default() -> JeroslowWangTwoSided

Returns the “default value” for a type.

impl<L: Literal> VariableSelection<L> for JeroslowWangTwoSided

fn new<C: AsRef<[L]>>(num_vars: usize, _: &[L], clauses: &[C]) -> Self

Creates a new JeroslowWangTwoSided strategy. Initialises scores using init_jw_scores. The random number generator is seeded with 0.

fn pick<A: Assignment>(&mut self, assignment: &A) -> Option<L>

Picks a variable and its polarity using the two-sided Jeroslow-Wang heuristic.

1. Finds the unassigned variable v maximising JW(v_pos) + JW(v_neg).
2. For the chosen v, selects the literal (positive or negative) with the higher JW score. Ties are broken randomly.
3. There is a 10% chance the polarity of this final literal is flipped.

fn bumps<T: IntoIterator<Item = L>>(&mut self, _: T)

Bumps scores. NO-OP for JeroslowWangTwoSided. JW scores are static.

fn decay(&mut self, _: f64)

Decays scores. NO-OP for JeroslowWangTwoSided. JW scores are static.

fn decisions(&self) -> usize

Returns the total number of decisions made by this strategy instance.