Struct GainRule 

pub struct GainRule { /* private fields */ }

Restricts a pass to the paths whose accumulated heuristic loss stays within a gap.

At each node, choosing a feature other than the best-ranked one loses the difference between their heuristic scores. The rule cuts the paths whose total loss exceeds the gap; relaxing it widens the gap by delta times the next step of its StepStrategy, up to limit.

Implementations

impl GainRule

pub fn new( gap: f64, delta: f64, limit: f64, increment: Box<dyn StepStrategy>, ) -> Self

A rule starting at gap, widened in steps of delta up to limit.

pub fn with_priority(self, priority: u8) -> Self

Sets the evaluation priority.

pub fn with_delay(self, delay: u8) -> Self

Sets the number of passes before the rule takes effect.

pub fn with_gap(self, gap: f64) -> Self

Sets the gap of the first pass.

pub fn with_limit(self, limit: f64) -> Self

Sets the largest gap.

pub fn update_gap_delta(&mut self, delta: f64)

Sets the step of the gap; ignored unless positive. The search sets it to the smallest loss seen in the first pass.

pub fn update_limit(&mut self, limit: f64)

Lowers the largest gap to limit.

Trait Implementations

impl Rule for GainRule

fn evaluate(&self, context: &RuleContext) -> RuleResult

Decides whether the search continues below the node.

fn priority(&self) -> u8

Rules with a higher priority are evaluated first.

fn description(&self) -> String

A short human-readable name.

fn state(&self) -> RuleState

The current state of the rule.

fn activate(&mut self)

Starts applying the rule; called before the first pass.

fn deactivate(&mut self)

Stops applying the rule.

fn is_relaxable(&self) -> bool

Whether the rule restricts the search only temporarily. A search whose pass was cut by a relaxable rule is not finished.

fn relax(&mut self)

Widens the rule’s budget before the next pass, or deactivates it once the budget is at its limit.

fn delay(&self) -> u8

Number of passes to wait before the rule takes effect.

fn as_any(&self) -> &dyn Any

Upcast used by RuleManager::get_rule_mut.

fn as_any_mut(&mut self) -> &mut dyn Any

Mutable upcast used by RuleManager::get_rule_mut.

fn is_active(&self) -> bool

Whether the rule is applied.

fn reset(&mut self)

Resets any internal state, such as a timer.