Struct EtdDispatch 

pub struct EtdDispatch {
    pub wait_weight: f64,
    pub delay_weight: f64,
    pub door_weight: f64,
    pub wait_squared_weight: f64,
    pub age_linear_weight: f64,
    /* private fields */
}

Estimated Time to Destination (ETD) dispatch algorithm.

For each (car, stop) pair the rank is a cost estimate combining travel time, delay imposed on riders already aboard, door-overhead for intervening stops, and a small bonus for cars already heading toward the stop. The dispatch system runs an optimal assignment across all pairs so the globally best matching is chosen.

Fields

wait_weight: f64

Weight for travel time to reach the calling stop.

delay_weight: f64

Weight for delay imposed on existing riders.

door_weight: f64

Weight for door open/close overhead at intermediate stops.

wait_squared_weight: f64

Weight for the squared-wait “group-time” fairness bonus. Each candidate stop’s cost is reduced by this weight times the sum of wait_ticks² across waiting riders at the stop, so stops hosting older calls win ties. Defaults to 0.0 (no bias); positive values damp the long-wait tail (Aalto EJOR 2016 group-time assignment model).

age_linear_weight: f64

Weight for the linear waiting-age fairness term. Each candidate stop’s cost is reduced by this weight times the sum of wait_ticks across waiting riders at the stop, so stops hosting older calls win ties without the quadratic blow-up of wait_squared_weight. Defaults to 0.0 (no bias); positive values implement the linear collective-group-control fairness term from Lim 1983 / Barney–dos Santos 1985 CGC.

Composes additively with wait_squared_weight: users wanting the full CGC shape can set both (k·Σw + λ·Σw²).

Implementations

impl EtdDispatch

pub fn new() -> Self

Create a new EtdDispatch with default weights.

Defaults: wait_weight = 1.0, delay_weight = 1.0, door_weight = 0.5, wait_squared_weight = 0.0, age_linear_weight = 0.0.

pub fn with_delay_weight(delay_weight: f64) -> Self

Create with a single delay weight (backwards-compatible shorthand).

pub fn with_weights( wait_weight: f64, delay_weight: f64, door_weight: f64, ) -> Self

Create with fully custom weights.

pub fn with_wait_squared_weight(self, weight: f64) -> Self

Turn on the squared-wait fairness bonus. Higher values prefer older waiters more aggressively; 0.0 (the default) disables.

Panics

Panics on non-finite or negative weights. A NaN weight would propagate through mul_add and silently disable every dispatch rank; a negative weight would invert the fairness ordering. Either is a programming error rather than a valid configuration.

pub fn with_age_linear_weight(self, weight: f64) -> Self

Turn on the linear waiting-age fairness term. Higher values prefer older waiters more aggressively; 0.0 (the default) disables. Composes additively with with_wait_squared_weight.

Panics

Panics on non-finite or negative weights, for the same reasons as with_wait_squared_weight.

Trait Implementations

impl Default for EtdDispatch

fn default() -> Self

Returns the “default value” for a type.

impl DispatchStrategy for EtdDispatch

fn pre_dispatch( &mut self, group: &ElevatorGroup, manifest: &DispatchManifest, world: &mut World, )

Optional hook called once per group before the assignment pass.

fn rank(&mut self, ctx: &RankContext<'_>) -> Option<f64>

Score the cost of sending car to stop. Lower is better.

fn prepare_car( &mut self, _car: EntityId, _car_position: f64, _group: &ElevatorGroup, _manifest: &DispatchManifest, _world: &World, )

Optional hook called once per candidate car, before any rank calls for that car in the current pass.

fn fallback( &mut self, _car: EntityId, _car_position: f64, _group: &ElevatorGroup, _manifest: &DispatchManifest, _world: &World, ) -> DispatchDecision

Decide what an idle car should do when no stop was assigned to it.

fn notify_removed(&mut self, _elevator: EntityId)

Notify the strategy that an elevator has been removed.