Struct BatchSizeController 

pub struct BatchSizeController {
    pub current_size: usize,
    pub loss_history: Vec<f64>,
    /* private fields */
}

Online controller that tracks a loss history and recommends a batch size.

Fields

current_size: usize

Current recommended batch size.

loss_history: Vec<f64>

Full history of recorded losses (oldest first).

Implementations

impl BatchSizeController

pub fn new(config: AdaptiveBatchConfig) -> Self

Create a new controller with the given configuration.

pub fn record_loss(&mut self, loss: f64)

Record a new loss value without updating the batch size recommendation.

pub fn recommend_size(&self) -> usize

Recommend a batch size based on the recorded loss history.

Decision rules (applied to the most recent window observations):

1. Not enough history → return current size unchanged.
2. Split history into last_half and prev_half (each window/2 long).
3. If std(last_half) / mean(last_half) < 0.01 → grow (stable descent).
4. If mean(last_half) > mean(prev_half) → shrink (loss increased).
5. Otherwise → no change.

pub fn adapt(&mut self, loss: f64) -> usize

Record loss, update current_size and return the new recommended size.

pub fn reset(&mut self)

Reset to initial state.

pub fn validate(&self) -> Result<(), ClusteringError>

Validate the configuration.