Struct SimulatedAnnealingAcceptor 

pub struct SimulatedAnnealingAcceptor { /* private fields */ }

Simulated annealing acceptor using the Boltzmann distribution.

Accepts improving moves unconditionally. For worsening moves, accepts with probability exp(-delta / T) where delta is the score degradation and T is the current temperature.

Temperature decays geometrically each step: T *= decay_rate.

Example

use solverforge_solver::phase::localsearch::SimulatedAnnealingAcceptor;

// High initial temperature (explores broadly), slow cooling
let acceptor = SimulatedAnnealingAcceptor::new(1.0, 0.9999);

Implementations

impl SimulatedAnnealingAcceptor

pub fn new(starting_temperature: f64, decay_rate: f64) -> Self

Creates a new simulated annealing acceptor.

Arguments

• starting_temperature - Initial temperature (higher = more exploration). Calibrate to ~20% of the initial hard score magnitude for best results.
• decay_rate - Multiplicative decay per step (e.g., 0.9999 for 30s runs at ~10k steps/s gives final T ≈ 0.05 * starting T).

pub fn with_seed(starting_temperature: f64, decay_rate: f64, seed: u64) -> Self

Creates a new SA acceptor with a fixed seed for reproducibility.

pub fn auto_calibrate(decay_rate: f64) -> Self

Auto-calibrates starting temperature from the initial score.

Sets temperature to 20% of the absolute initial score magnitude, ensuring ~80% acceptance probability for moves with delta = |initial_score|.

Trait Implementations

impl<S: PlanningSolution> Acceptor<S> for SimulatedAnnealingAcceptor

where S::Score: Score,

fn is_accepted( &mut self, last_step_score: &S::Score, move_score: &S::Score, ) -> bool

Returns true if a move resulting in move_score should be accepted, given the previous step’s score.

fn phase_started(&mut self, initial_score: &S::Score)

Called when a phase starts.

fn step_ended(&mut self, _step_score: &S::Score)

Called when a step ends with an accepted move.

fn phase_ended(&mut self)

Called when a phase ends.

fn step_started(&mut self)

Called when a step starts.

impl Debug for SimulatedAnnealingAcceptor

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

Formats the value using the given formatter.

impl Default for SimulatedAnnealingAcceptor

fn default() -> Self

Returns the “default value” for a type.