Struct Ceiling 

pub struct Ceiling { /* private fields */ }

Prunes a trial whose first objective is worse than a fixed bound once it has reached a given step.

“Worse” follows the study’s first Direction: above the bound when minimizing, below it when maximizing. A report equal to the bound continues. A NaN report is pruned, because a run that diverged has nothing left to show, and Direction::is_better would otherwise let it run to the end. Reports before from_step always continue, which is the warm-up every learning curve needs before its value means anything.

A pruner in the sense of the guide’s Write a scheduler page: it only ever answers [Decision::Continue] or [Decision::Prune], so it needs neither on_trial_end nor resume_candidates, and it persists nothing.

Implementations

impl Ceiling

pub fn try_new(bound: f64, from_step: u64) -> Result<Self>

Creates the scheduler.

Errors

[Error::Scheduler] for a bound that is not finite: a NaN bound would never compare, and an infinite one would prune every trial or none, which is a configuration mistake rather than a policy.

Trait Implementations

impl Clone for Ceiling

fn clone(&self) -> Ceiling

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Ceiling

impl Debug for Ceiling

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

Formats the value using the given formatter.

impl PartialEq for Ceiling

fn eq(&self, other: &Ceiling) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Scheduler for Ceiling

fn fan_report_mode(&self) -> FanReportMode

Accepts a multi-seed fan’s aligned aggregate.

Safe to opt into because a decision reads one value at one step and nothing else: the aggregate of a fan is exactly such a value, and the decision applies to the whole logical trial.

fn on_report( &self, study: &StudyView, _trial: &TrialMeta, step: u64, values: &[f64], ) -> Result<Decision>

Prunes a report worse than the bound at or after from_step.

Errors

[Error::Scheduler] for a report that carries no value, or a study with no direction. The study loop reads either as “no decision” and lets the trial continue, which is the seam’s rule for a scheduler that cannot decide.

fn scripted_capability(&self) -> ScriptedSchedulerCapability

Declares whether scripted ask/tell can recreate this scheduler.

fn population_report_mode(&self) -> PopulationReportMode

Declares whether this scheduler accepts one shared report batch from several population members. This is distinct from fanned replicate reports. The default is fail-closed.

fn on_population_report( &self, study: &StudyView, reports: &[PopulationReport], ) -> Result<Vec<PopulationDecision>, Error>

Decides all members at one population boundary from the same snapshot.

fn on_trial_end( &self, study: &StudyView, trial: &FrozenTrial, ) -> Result<Vec<Command>, Error>

Called once a trial reaches a terminal state.

fn resume_candidates(&self, study: &StudyView) -> Result<Vec<Command>, Error>

Paused trials worth waking on a freed work slot, in priority order.

fn state(&self) -> Result<Option<StateBlob>, Error>

The scheduler’s persistable state, if it has any.

fn restore_state(&self, blob: &StateBlob) -> Result<(), Error>

Restores a scheduler from a previously persisted blob.

impl StructuralPartialEq for Ceiling