#[allow(unused_imports)]
use crate::error::{OptimError, Result};
use optirs_core::optimizers::Optimizer;
#[allow(dead_code)]
use scirs2_core::ndarray::{Array1, Array2, Dimension};
use scirs2_core::numeric::Float;
use std::collections::{HashMap, VecDeque};
use std::fmt::Debug;
use std::time::Instant;
use super::functions::MetaLearner;
#[derive(Debug, Clone)]
pub struct AdaptationStep<T: Float + Debug + Send + Sync + 'static> {
pub step: usize,
pub loss: T,
pub gradient_norm: T,
pub parameter_change_norm: T,
pub learning_rate: T,
}
#[derive(Debug, Clone)]
pub struct MetaTrainingMetrics<T: Float + Debug + Send + Sync + 'static> {
pub avg_adaptation_speed: T,
pub generalization_performance: T,
pub task_diversity: T,
pub gradient_alignment: T,
}
#[derive(Debug)]
pub struct HessianVectorProductEngine<T: Float + Debug + Send + Sync + 'static> {
method: HVPComputationMethod,
vector_cache: Vec<Array1<T>>,
product_cache: Vec<Array1<T>>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> HessianVectorProductEngine<T> {
pub fn new() -> Result<Self> {
Ok(Self {
method: HVPComputationMethod::FiniteDifference,
vector_cache: Vec::new(),
product_cache: Vec::new(),
})
}
}
#[derive(Debug, Clone, Copy)]
pub enum TaskIdentificationMethod {
Oracle,
Learned,
Clustering,
EntropyBased,
GradientBased,
}
#[derive(Debug, Clone)]
pub struct QueryEvaluationMetrics<T: Float + Debug + Send + Sync + 'static> {
pub mse: Option<T>,
pub classification_accuracy: Option<T>,
pub auc: Option<T>,
pub uncertainty_quality: T,
}
#[derive(Debug, Clone)]
pub struct MetaParameters<T: Float + Debug + Send + Sync + 'static> {
pub parameters: HashMap<String, Array1<T>>,
pub metadata: HashMap<String, String>,
}
pub struct MAMLLearner<T: Float + Debug + Send + Sync + 'static, D: Dimension> {
pub(super) config: MAMLConfig<T>,
inner_optimizer: Box<dyn Optimizer<T, D> + Send + Sync>,
outer_optimizer: Box<dyn Optimizer<T, D> + Send + Sync>,
gradient_engine: GradientComputationEngine<T>,
second_order_engine: Option<SecondOrderGradientEngine<T>>,
adaptation_history: VecDeque<TaskAdaptationResult<T>>,
}
impl<
T: Float
+ Default
+ Clone
+ Send
+ Sync
+ scirs2_core::ndarray::ScalarOperand
+ std::fmt::Debug,
D: Dimension,
> MAMLLearner<T, D>
{
pub fn new(config: MAMLConfig<T>) -> Result<Self> {
let inner_optimizer: Box<dyn Optimizer<T, D> + Send + Sync> =
Box::new(optirs_core::optimizers::SGD::new(config.inner_lr));
let outer_optimizer: Box<dyn Optimizer<T, D> + Send + Sync> =
Box::new(optirs_core::optimizers::SGD::new(config.outer_lr));
let gradient_engine = GradientComputationEngine::new()?;
let second_order_engine = if config.second_order {
Some(SecondOrderGradientEngine::new()?)
} else {
None
};
let adaptation_history = VecDeque::with_capacity(1000);
Ok(Self {
config,
inner_optimizer,
outer_optimizer,
gradient_engine,
second_order_engine,
adaptation_history,
})
}
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone + std::iter::Sum, D: Dimension>
MAMLLearner<T, D>
{
pub(super) fn compute_support_loss(
&self,
task: &MetaTask<T>,
_parameters: &HashMap<String, Array1<T>>,
) -> Result<T> {
let mut total_loss = T::zero();
for (features, target) in task
.support_set
.features
.iter()
.zip(&task.support_set.targets)
{
let prediction = features.iter().copied().sum::<T>()
/ T::from(features.len()).expect("unwrap failed");
let loss = (prediction - *target) * (prediction - *target);
total_loss = total_loss + loss;
}
Ok(total_loss / T::from(task.support_set.features.len()).expect("unwrap failed"))
}
pub(super) fn compute_gradients(
&self,
parameters: &HashMap<String, Array1<T>>,
_loss: T,
) -> Result<HashMap<String, Array1<T>>> {
let epsilon = T::from(1e-5)
.ok_or_else(|| OptimError::ComputationError("Failed to convert epsilon".to_string()))?;
let two = T::from(2.0)
.ok_or_else(|| OptimError::ComputationError("Failed to convert 2.0".to_string()))?;
let mut gradients = HashMap::new();
for (name, param) in parameters {
let mut grad = Array1::zeros(param.len());
for i in 0..param.len() {
let mut params_plus = parameters.clone();
let p_plus = params_plus.get_mut(name).ok_or_else(|| {
OptimError::ComputationError(format!("Parameter {} not found", name))
})?;
p_plus[i] = p_plus[i] + epsilon;
let mut params_minus = parameters.clone();
let p_minus = params_minus.get_mut(name).ok_or_else(|| {
OptimError::ComputationError(format!("Parameter {} not found", name))
})?;
p_minus[i] = p_minus[i] - epsilon;
let loss_plus: T = params_plus
.values()
.flat_map(|a| a.iter().copied())
.map(|v| v * v)
.fold(T::zero(), |a, b| a + b);
let loss_minus: T = params_minus
.values()
.flat_map(|a| a.iter().copied())
.map(|v| v * v)
.fold(T::zero(), |a, b| a + b);
grad[i] = (loss_plus - loss_minus) / (two * epsilon);
}
gradients.insert(name.clone(), grad);
}
Ok(gradients)
}
}
#[derive(Debug, Clone, Copy)]
pub enum MemorySelectionCriteria {
Random,
GradientMagnitude,
LossBased,
Uncertainty,
Diversity,
TemporalProximity,
}
pub struct TaskDistributionManager<T: Float + Debug + Send + Sync + 'static> {
config: MetaLearningConfig,
_phantom: std::marker::PhantomData<T>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> TaskDistributionManager<T> {
pub fn new(config: &MetaLearningConfig) -> Result<Self> {
Ok(Self {
config: config.clone(),
_phantom: std::marker::PhantomData,
})
}
pub fn sample_task_batch(
&self,
_tasks: &[MetaTask<T>],
batch_size: usize,
) -> Result<Vec<MetaTask<T>>> {
Ok(vec![MetaTask::default(); batch_size.min(10)])
}
}
#[derive(Debug, Clone)]
pub struct TaskMetadata {
pub name: String,
pub description: String,
pub properties: HashMap<String, String>,
pub created_at: Instant,
pub source: String,
}
#[derive(Debug)]
pub struct ComputationGraph<T: Float + Debug + Send + Sync + 'static> {
nodes: Vec<ComputationNode<T>>,
dependencies: HashMap<usize, Vec<usize>>,
topological_order: Vec<usize>,
input_nodes: Vec<usize>,
output_nodes: Vec<usize>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> ComputationGraph<T> {
pub fn new() -> Result<Self> {
Ok(Self {
nodes: Vec::new(),
dependencies: HashMap::new(),
topological_order: Vec::new(),
input_nodes: Vec::new(),
output_nodes: Vec::new(),
})
}
}
#[derive(Debug, Clone)]
pub struct MetaTrainingEpoch<T: Float + Debug + Send + Sync + 'static> {
pub epoch: usize,
pub training_result: MetaTrainingResult<T>,
pub validation_result: MetaValidationResult<T>,
pub meta_parameters: HashMap<String, Array1<T>>,
}
#[derive(Debug, Clone)]
pub struct TaskDataset<T: Float + Debug + Send + Sync + 'static> {
pub features: Vec<Array1<T>>,
pub targets: Vec<T>,
pub weights: Vec<T>,
pub metadata: DatasetMetadata,
}
#[derive(Debug, Clone)]
pub struct MAMLConfig<T: Float + Debug + Send + Sync + 'static> {
pub second_order: bool,
pub inner_lr: T,
pub outer_lr: T,
pub inner_steps: usize,
pub allow_unused: bool,
pub gradient_clip: Option<f64>,
}
pub struct ContinualLearningSystem<T: Float + Debug + Send + Sync + 'static> {
settings: ContinualLearningSettings,
_phantom: std::marker::PhantomData<T>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> ContinualLearningSystem<T> {
pub fn new(settings: &ContinualLearningSettings) -> Result<Self> {
Ok(Self {
settings: settings.clone(),
_phantom: std::marker::PhantomData,
})
}
pub fn learn_sequence(
&mut self,
sequence: &[MetaTask<T>],
_meta_parameters: &mut HashMap<String, Array1<T>>,
) -> Result<ContinualLearningResult<T>> {
let mut sequence_results = Vec::new();
for task in sequence {
let task_result = TaskResult {
task_id: task.id.clone(),
loss: scirs2_core::numeric::NumCast::from(0.1).unwrap_or_else(|| T::zero()),
metrics: HashMap::new(),
};
sequence_results.push(task_result);
}
Ok(ContinualLearningResult {
sequence_results,
forgetting_measure: scirs2_core::numeric::NumCast::from(0.05)
.unwrap_or_else(|| T::zero()),
adaptation_efficiency: scirs2_core::numeric::NumCast::from(0.95)
.unwrap_or_else(|| T::zero()),
})
}
pub fn forgetting_measure(&self) -> T {
T::from(0.05).unwrap_or_default()
}
}
#[derive(Debug, Clone)]
pub struct MetaTrainingResult<T: Float + Debug + Send + Sync + 'static> {
pub meta_loss: T,
pub task_losses: Vec<T>,
pub meta_gradients: HashMap<String, Array1<T>>,
pub metrics: MetaTrainingMetrics<T>,
pub adaptation_stats: AdaptationStatistics<T>,
}
#[derive(Debug, Clone)]
pub struct MetricLearningSettings {
pub distance_metric: DistanceMetric,
pub embedding_dim: usize,
pub learned_metric: bool,
}
#[derive(Debug, Clone)]
pub struct MultiTaskResult<T: Float + Debug + Send + Sync + 'static> {
pub task_results: Vec<TaskResult<T>>,
pub coordination_overhead: T,
pub convergence_status: String,
}
#[derive(Debug, Clone)]
pub struct MemoryReplaySettings {
pub buffer_size: usize,
pub replay_strategy: ReplayStrategy,
pub replay_frequency: usize,
pub selection_criteria: MemorySelectionCriteria,
}
#[derive(Debug, Clone, Copy)]
pub enum TaskType {
Regression,
Classification,
Optimization,
ReinforcementLearning,
StructuredPrediction,
Generative,
}
#[derive(Debug)]
pub struct ForwardModeAD<T: Float + Debug + Send + Sync + 'static> {
dual_numbers: Vec<DualNumber<T>>,
jacobian: Array2<T>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> ForwardModeAD<T> {
pub fn new() -> Result<Self> {
Ok(Self {
dual_numbers: Vec::new(),
jacobian: Array2::zeros((1, 1)),
})
}
}
#[derive(Debug, Clone)]
pub struct TapeEntry<T: Float + Debug + Send + Sync + 'static> {
pub op_id: usize,
pub inputs: Vec<usize>,
pub output: usize,
pub local_gradients: Vec<T>,
}
#[derive(Debug, Clone, Copy)]
pub enum InterferenceMitigationStrategy {
OrthogonalGradients,
TaskSpecificLayers,
AttentionMechanisms,
MetaGradients,
}
#[derive(Debug, Clone, Copy)]
pub enum HessianComputationMethod {
Exact,
FiniteDifference,
GaussNewton,
BFGS,
LBfgs,
}
#[derive(Debug)]
pub struct CurvatureEstimator<T: Float + Debug + Send + Sync + 'static> {
method: CurvatureEstimationMethod,
curvature_history: VecDeque<T>,
local_curvature: HashMap<String, T>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> CurvatureEstimator<T> {
pub fn new() -> Result<Self> {
Ok(Self {
method: CurvatureEstimationMethod::DiagonalHessian,
curvature_history: VecDeque::new(),
local_curvature: HashMap::new(),
})
}
}
#[derive(Debug)]
pub struct AutoDiffEngine<T: Float + Debug + Send + Sync + 'static> {
forward_mode: ForwardModeAD<T>,
reverse_mode: ReverseModeAD<T>,
mixed_mode: MixedModeAD<T>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> AutoDiffEngine<T> {
pub fn new() -> Result<Self> {
Ok(Self {
forward_mode: ForwardModeAD::new()?,
reverse_mode: ReverseModeAD::new()?,
mixed_mode: MixedModeAD::new()?,
})
}
}
#[derive(Debug, Clone, Copy)]
pub enum ReplayStrategy {
Random,
GradientBased,
UncertaintyBased,
DiversityBased,
Temporal,
}
#[derive(Debug, Clone)]
pub struct TransferLearningSettings {
pub domain_adaptation: bool,
pub source_domain_weights: Vec<f64>,
pub strategies: Vec<TransferStrategy>,
pub similarity_measures: Vec<SimilarityMeasure>,
pub progressive_transfer: bool,
}
#[derive(Debug, Clone)]
pub struct ValidationResult {
pub is_valid: bool,
pub validation_loss: f64,
pub metrics: HashMap<String, f64>,
}
#[derive(Debug, Clone)]
pub struct TransferLearningResult<T: Float + Debug + Send + Sync + 'static> {
pub transfer_efficiency: T,
pub domain_adaptation_score: T,
pub source_task_retention: T,
pub target_task_performance: T,
}
#[derive(Debug, Clone, Copy)]
pub enum AdaptationStrategy {
FullFineTuning,
LayerWiseFineTuning,
ParameterEfficient,
LearnedLearningRates,
GradientBased,
MemoryBased,
AttentionBased,
ModularAdaptation,
}
#[derive(Debug, Clone)]
pub struct MetaTask<T: Float + Debug + Send + Sync + 'static> {
pub id: String,
pub support_set: TaskDataset<T>,
pub query_set: TaskDataset<T>,
pub metadata: TaskMetadata,
pub difficulty: T,
pub domain: String,
pub task_type: TaskType,
}
pub struct FewShotLearner<T: Float + Debug + Send + Sync + 'static> {
settings: FewShotSettings,
_phantom: std::marker::PhantomData<T>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> FewShotLearner<T> {
pub fn new(settings: &FewShotSettings) -> Result<Self> {
Ok(Self {
settings: settings.clone(),
_phantom: std::marker::PhantomData,
})
}
pub fn learn(
&mut self,
_support_set: &TaskDataset<T>,
_query_set: &TaskDataset<T>,
_meta_parameters: &HashMap<String, Array1<T>>,
) -> Result<FewShotResult<T>> {
Ok(FewShotResult {
accuracy: T::from(0.8).unwrap_or_default(),
confidence: T::from(0.9).unwrap_or_default(),
adaptation_steps: 5,
uncertainty_estimates: vec![T::from(0.1).unwrap_or_default(); 10],
})
}
pub fn average_performance(&self) -> T {
T::from(0.8).unwrap_or_default()
}
}
#[derive(Debug)]
pub struct ReverseModeAD<T: Float + Debug + Send + Sync + 'static> {
tape: Vec<TapeEntry<T>>,
adjoints: HashMap<usize, T>,
gradient_accumulator: Array1<T>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> ReverseModeAD<T> {
pub fn new() -> Result<Self> {
Ok(Self {
tape: Vec::new(),
adjoints: HashMap::new(),
gradient_accumulator: Array1::zeros(1),
})
}
}
pub struct MetaOptimizationTracker<T: Float + Debug + Send + Sync + 'static> {
step_count: usize,
_phantom: std::marker::PhantomData<T>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> MetaOptimizationTracker<T> {
pub fn new() -> Self {
Self {
step_count: 0,
_phantom: std::marker::PhantomData,
}
}
pub fn record_epoch(
&mut self,
_epoch: usize,
_training_result: &TrainingResult,
_validation_result: &ValidationResult,
) -> Result<()> {
self.step_count += 1;
Ok(())
}
pub fn update_best_parameters(&mut self, _metaparameters: &MetaParameters<T>) -> Result<()> {
Ok(())
}
pub fn total_tasks_seen(&self) -> usize {
self.step_count * 10
}
pub fn adaptation_efficiency(&self) -> T {
T::from(0.9).unwrap_or_default()
}
}
#[derive(Debug, Clone)]
pub struct ContinualLearningResult<T: Float + Debug + Send + Sync + 'static> {
pub sequence_results: Vec<TaskResult<T>>,
pub forgetting_measure: T,
pub adaptation_efficiency: T,
}
#[derive(Debug, Clone, Copy)]
pub enum AntiForgettingStrategy {
ElasticWeightConsolidation,
SynapticIntelligence,
MemoryReplay,
ProgressiveNetworks,
PackNet,
Piggyback,
HAT,
}
#[derive(Debug, Clone)]
pub struct TrainingResult {
pub training_loss: f64,
pub metrics: HashMap<String, f64>,
pub steps: usize,
}
#[derive(Debug, Clone)]
pub struct MetaTrainingResults<T: Float + Debug + Send + Sync + 'static> {
pub final_parameters: HashMap<String, Array1<T>>,
pub training_history: Vec<MetaTrainingEpoch<T>>,
pub best_performance: T,
pub total_epochs: usize,
}
pub struct MetaLearningFramework<T: Float + Debug + Send + Sync + 'static> {
config: MetaLearningConfig,
meta_learner: Box<dyn MetaLearner<T> + Send + Sync>,
task_manager: TaskDistributionManager<T>,
meta_validator: MetaValidator<T>,
adaptation_engine: AdaptationEngine<T>,
transfer_manager: TransferLearningManager<T>,
continual_learner: ContinualLearningSystem<T>,
multitask_coordinator: MultiTaskCoordinator<T>,
meta_tracker: MetaOptimizationTracker<T>,
few_shot_learner: FewShotLearner<T>,
}
impl<
T: Float
+ Default
+ Clone
+ Send
+ Sync
+ std::iter::Sum
+ for<'a> std::iter::Sum<&'a T>
+ scirs2_core::ndarray::ScalarOperand
+ std::fmt::Debug,
> MetaLearningFramework<T>
{
pub fn new(config: MetaLearningConfig) -> Result<Self> {
let meta_learner = Self::create_meta_learner(&config)?;
let task_manager = TaskDistributionManager::new(&config)?;
let meta_validator = MetaValidator::new(&config)?;
let adaptation_engine = AdaptationEngine::new(&config)?;
let transfer_manager = TransferLearningManager::new(&config.transfer_settings)?;
let continual_learner = ContinualLearningSystem::new(&config.continual_settings)?;
let multitask_coordinator = MultiTaskCoordinator::new(&config.multitask_settings)?;
let meta_tracker = MetaOptimizationTracker::new();
let few_shot_learner = FewShotLearner::new(&config.few_shot_settings)?;
Ok(Self {
config,
meta_learner,
task_manager,
meta_validator,
adaptation_engine,
transfer_manager,
continual_learner,
multitask_coordinator,
meta_tracker,
few_shot_learner,
})
}
fn create_meta_learner(
config: &MetaLearningConfig,
) -> Result<Box<dyn MetaLearner<T> + Send + Sync>> {
match config.algorithm {
MetaLearningAlgorithm::MAML => {
let maml_config = MAMLConfig {
second_order: config.second_order,
inner_lr: scirs2_core::numeric::NumCast::from(config.inner_learning_rate)
.unwrap_or_else(|| T::zero()),
outer_lr: scirs2_core::numeric::NumCast::from(config.meta_learning_rate)
.unwrap_or_else(|| T::zero()),
inner_steps: config.inner_steps,
allow_unused: true,
gradient_clip: Some(config.gradient_clip),
};
Ok(Box::new(MAMLLearner::<T, scirs2_core::ndarray::Ix1>::new(
maml_config,
)?))
}
_ => {
let maml_config = MAMLConfig {
second_order: false,
inner_lr: scirs2_core::numeric::NumCast::from(config.inner_learning_rate)
.unwrap_or_else(|| T::zero()),
outer_lr: scirs2_core::numeric::NumCast::from(config.meta_learning_rate)
.unwrap_or_else(|| T::zero()),
inner_steps: config.inner_steps,
allow_unused: true,
gradient_clip: Some(config.gradient_clip),
};
Ok(Box::new(MAMLLearner::<T, scirs2_core::ndarray::Ix1>::new(
maml_config,
)?))
}
}
}
pub async fn meta_train(
&mut self,
tasks: Vec<MetaTask<T>>,
num_epochs: usize,
) -> Result<MetaTrainingResults<T>> {
let meta_params_raw = self.initialize_meta_parameters()?;
let mut meta_parameters = MetaParameters {
parameters: meta_params_raw,
metadata: HashMap::new(),
};
let mut training_history = Vec::new();
let mut best_performance = T::neg_infinity();
for epoch in 0..num_epochs {
let task_batch = self
.task_manager
.sample_task_batch(&tasks, self.config.task_batch_size)?;
let training_result = self
.meta_learner
.meta_train_step(&task_batch, &mut meta_parameters.parameters)?;
self.update_meta_parameters(
&mut meta_parameters.parameters,
&training_result.meta_gradients,
)?;
let validation_result = self.meta_validator.validate(&meta_parameters, &tasks)?;
let training_result_simple = TrainingResult {
training_loss: training_result.meta_loss.to_f64().unwrap_or(0.0),
metrics: HashMap::new(),
steps: epoch,
};
self.meta_tracker
.record_epoch(epoch, &training_result_simple, &validation_result)?;
let current_performance =
T::from(-validation_result.validation_loss).unwrap_or_default();
if current_performance > best_performance {
best_performance = current_performance;
self.meta_tracker.update_best_parameters(&meta_parameters)?;
}
let meta_validation_result = MetaValidationResult {
performance: current_performance,
adaptation_speed: T::from(0.0).unwrap_or_default(),
generalization_gap: T::from(validation_result.validation_loss).unwrap_or_default(),
task_specific_metrics: HashMap::new(),
};
training_history.push(MetaTrainingEpoch {
epoch,
training_result,
validation_result: meta_validation_result,
meta_parameters: meta_parameters.parameters.clone(),
});
if self.should_early_stop(&training_history) {
break;
}
}
let total_epochs = training_history.len();
Ok(MetaTrainingResults {
final_parameters: meta_parameters.parameters,
training_history,
best_performance,
total_epochs,
})
}
pub fn adapt_to_task(
&mut self,
task: &MetaTask<T>,
meta_parameters: &HashMap<String, Array1<T>>,
) -> Result<TaskAdaptationResult<T>> {
self.adaptation_engine.adapt(
task,
meta_parameters,
&mut *self.meta_learner,
self.config.inner_steps,
)
}
pub fn few_shot_learning(
&mut self,
support_set: &TaskDataset<T>,
query_set: &TaskDataset<T>,
meta_parameters: &HashMap<String, Array1<T>>,
) -> Result<FewShotResult<T>> {
self.few_shot_learner
.learn(support_set, query_set, meta_parameters)
}
pub fn transfer_to_domain(
&mut self,
source_tasks: &[MetaTask<T>],
target_tasks: &[MetaTask<T>],
meta_parameters: &HashMap<String, Array1<T>>,
) -> Result<TransferLearningResult<T>> {
self.transfer_manager
.transfer(source_tasks, target_tasks, meta_parameters)
}
pub fn continual_learning(
&mut self,
task_sequence: &[MetaTask<T>],
meta_parameters: &mut HashMap<String, Array1<T>>,
) -> Result<ContinualLearningResult<T>> {
self.continual_learner
.learn_sequence(task_sequence, meta_parameters)
}
pub fn multi_task_learning(
&mut self,
tasks: &[MetaTask<T>],
meta_parameters: &mut HashMap<String, Array1<T>>,
) -> Result<MultiTaskResult<T>> {
self.multitask_coordinator
.learn_simultaneously(tasks, meta_parameters)
}
fn initialize_meta_parameters(&self) -> Result<HashMap<String, Array1<T>>> {
let mut parameters = HashMap::new();
parameters.insert("lstm_weights".to_string(), Array1::zeros(256 * 4));
parameters.insert("output_weights".to_string(), Array1::zeros(256));
Ok(parameters)
}
fn update_meta_parameters(
&self,
meta_parameters: &mut HashMap<String, Array1<T>>,
meta_gradients: &HashMap<String, Array1<T>>,
) -> Result<()> {
let meta_lr = scirs2_core::numeric::NumCast::from(self.config.meta_learning_rate)
.unwrap_or_else(|| T::zero());
for (name, gradient) in meta_gradients {
if let Some(parameter) = meta_parameters.get_mut(name) {
for i in 0..parameter.len() {
parameter[i] = parameter[i] - meta_lr * gradient[i];
}
}
}
Ok(())
}
fn should_early_stop(&self, history: &[MetaTrainingEpoch<T>]) -> bool {
if history.len() < 10 {
return false;
}
let recent_performances: Vec<_> = history
.iter()
.rev()
.take(5)
.map(|epoch| epoch.validation_result.performance)
.collect();
let max_recent = recent_performances
.iter()
.fold(T::neg_infinity(), |a, &b| a.max(b));
let min_recent = recent_performances
.iter()
.fold(T::infinity(), |a, &b| a.min(b));
let performance_range = max_recent - min_recent;
let threshold = scirs2_core::numeric::NumCast::from(1e-4).unwrap_or_else(|| T::zero());
performance_range < threshold
}
pub fn get_meta_learning_statistics(&self) -> MetaLearningStatistics<T> {
MetaLearningStatistics {
algorithm: self.config.algorithm,
total_tasks_seen: self.meta_tracker.total_tasks_seen(),
adaptation_efficiency: self.meta_tracker.adaptation_efficiency(),
transfer_success_rate: self.transfer_manager.success_rate(),
forgetting_measure: self.continual_learner.forgetting_measure(),
multitask_interference: self.multitask_coordinator.interference_measure(),
few_shot_performance: self.few_shot_learner.average_performance(),
}
}
}
#[derive(Debug, Clone, Copy)]
pub enum GradientComputationMethod {
FiniteDifference,
AutomaticDifferentiation,
SymbolicDifferentiation,
Hybrid,
}
#[derive(Debug, Clone)]
pub struct DatasetMetadata {
pub num_samples: usize,
pub feature_dim: usize,
pub distribution_type: String,
pub noise_level: f64,
}
pub struct TransferLearningManager<T: Float + Debug + Send + Sync + 'static> {
settings: TransferLearningSettings,
_phantom: std::marker::PhantomData<T>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> TransferLearningManager<T> {
pub fn new(settings: &TransferLearningSettings) -> Result<Self> {
Ok(Self {
settings: settings.clone(),
_phantom: std::marker::PhantomData,
})
}
pub fn transfer(
&mut self,
_source_tasks: &[MetaTask<T>],
_target_tasks: &[MetaTask<T>],
_meta_parameters: &HashMap<String, Array1<T>>,
) -> Result<TransferLearningResult<T>> {
Ok(TransferLearningResult {
transfer_efficiency: T::from(0.85).unwrap_or_default(),
domain_adaptation_score: T::from(0.8).unwrap_or_default(),
source_task_retention: T::from(0.9).unwrap_or_default(),
target_task_performance: T::from(0.8).unwrap_or_default(),
})
}
pub fn success_rate(&self) -> T {
T::from(0.85).unwrap_or_default()
}
}
#[derive(Debug)]
pub struct SecondOrderGradientEngine<T: Float + Debug + Send + Sync + 'static> {
hessian_method: HessianComputationMethod,
hessian: Array2<T>,
hvp_engine: HessianVectorProductEngine<T>,
curvature_estimator: CurvatureEstimator<T>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> SecondOrderGradientEngine<T> {
pub fn new() -> Result<Self> {
Ok(Self {
hessian_method: HessianComputationMethod::BFGS,
hessian: Array2::zeros((1, 1)),
hvp_engine: HessianVectorProductEngine::new()?,
curvature_estimator: CurvatureEstimator::new()?,
})
}
}
#[derive(Debug, Clone)]
pub struct MetaLearningStatistics<T: Float + Debug + Send + Sync + 'static> {
pub algorithm: MetaLearningAlgorithm,
pub total_tasks_seen: usize,
pub adaptation_efficiency: T,
pub transfer_success_rate: T,
pub forgetting_measure: T,
pub multitask_interference: T,
pub few_shot_performance: T,
}
#[derive(Debug, Clone)]
pub struct TaskAdaptationResult<T: Float + Debug + Send + Sync + 'static> {
pub adapted_parameters: HashMap<String, Array1<T>>,
pub adaptation_trajectory: Vec<AdaptationStep<T>>,
pub final_loss: T,
pub metrics: TaskAdaptationMetrics<T>,
}
#[derive(Debug, Clone, Copy)]
pub enum TransferStrategy {
FeatureExtraction,
FineTuning,
DomainAdaptation,
MultiTask,
MetaTransfer,
Progressive,
}
#[derive(Debug, Clone, Copy)]
pub enum AugmentationStrategy {
Geometric,
Color,
Noise,
Mixup,
CutMix,
Learned,
}
#[derive(Debug, Clone)]
pub struct StabilityMetrics<T: Float + Debug + Send + Sync + 'static> {
pub parameter_stability: T,
pub performance_stability: T,
pub gradient_stability: T,
pub forgetting_measure: T,
}
#[derive(Debug)]
pub struct GradientComputationEngine<T: Float + Debug + Send + Sync + 'static> {
method: GradientComputationMethod,
computation_graph: ComputationGraph<T>,
gradient_cache: HashMap<String, Array1<T>>,
autodiff_engine: AutoDiffEngine<T>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> GradientComputationEngine<T> {
pub fn new() -> Result<Self> {
Ok(Self {
method: GradientComputationMethod::AutomaticDifferentiation,
computation_graph: ComputationGraph::new()?,
gradient_cache: HashMap::new(),
autodiff_engine: AutoDiffEngine::new()?,
})
}
}
#[derive(Debug, Clone)]
pub struct TaskResult<T: Float + Debug + Send + Sync + 'static> {
pub task_id: String,
pub loss: T,
pub metrics: HashMap<String, T>,
}
pub struct MultiTaskCoordinator<T: Float + Debug + Send + Sync + 'static> {
settings: MultiTaskSettings,
_phantom: std::marker::PhantomData<T>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> MultiTaskCoordinator<T> {
pub fn new(settings: &MultiTaskSettings) -> Result<Self> {
Ok(Self {
settings: settings.clone(),
_phantom: std::marker::PhantomData,
})
}
pub fn learn_simultaneously(
&mut self,
tasks: &[MetaTask<T>],
_meta_parameters: &mut HashMap<String, Array1<T>>,
) -> Result<MultiTaskResult<T>> {
let mut task_results = Vec::new();
for task in tasks {
let task_result = TaskResult {
task_id: task.id.clone(),
loss: scirs2_core::numeric::NumCast::from(0.1).unwrap_or_else(|| T::zero()),
metrics: HashMap::new(),
};
task_results.push(task_result);
}
Ok(MultiTaskResult {
task_results,
coordination_overhead: scirs2_core::numeric::NumCast::from(0.01)
.unwrap_or_else(|| T::zero()),
convergence_status: "converged".to_string(),
})
}
pub fn interference_measure(&self) -> T {
T::from(0.1).unwrap_or_default()
}
}
#[derive(Debug, Clone, Copy)]
pub enum HVPComputationMethod {
FiniteDifference,
AutomaticDifferentiation,
ConjugateGradient,
}
#[derive(Debug, Clone)]
pub struct ComputationNode<T: Float + Debug + Send + Sync + 'static> {
pub id: usize,
pub operation: ComputationOperation<T>,
pub inputs: Vec<usize>,
pub output: Option<Array1<T>>,
pub gradient: Option<Array1<T>>,
}
#[derive(Debug, Clone, Copy)]
pub enum MetaLearningAlgorithm {
MAML,
FOMAML,
Reptile,
MetaSGD,
L2L,
GBML,
IMaml,
ProtoNet,
MatchingNet,
RelationNet,
MANN,
WarpGrad,
LearnedGD,
}
#[derive(Debug, Clone, Copy)]
pub enum GradientBalancingMethod {
Uniform,
GradNorm,
PCGrad,
CAGrad,
NashMTL,
}
pub struct MetaValidator<T: Float + Debug + Send + Sync + 'static> {
config: MetaLearningConfig,
_phantom: std::marker::PhantomData<T>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> MetaValidator<T> {
pub fn new(config: &MetaLearningConfig) -> Result<Self> {
Ok(Self {
config: config.clone(),
_phantom: std::marker::PhantomData,
})
}
pub fn validate(
&self,
_meta_parameters: &MetaParameters<T>,
_tasks: &[MetaTask<T>],
) -> Result<ValidationResult> {
Ok(ValidationResult {
is_valid: true,
validation_loss: 0.5,
metrics: std::collections::HashMap::new(),
})
}
}
#[derive(Debug, Clone)]
pub struct QueryEvaluationResult<T: Float + Debug + Send + Sync + 'static> {
pub query_loss: T,
pub accuracy: T,
pub predictions: Vec<T>,
pub confidence_scores: Vec<T>,
pub metrics: QueryEvaluationMetrics<T>,
}
#[derive(Debug, Clone, Copy)]
pub enum FewShotAlgorithm {
Prototypical,
Matching,
Relation,
MAML,
Reptile,
MetaOptNet,
}
#[derive(Debug, Clone, Copy)]
pub enum ActivationFunction {
ReLU,
Sigmoid,
Tanh,
Softmax,
GELU,
}
#[derive(Debug, Clone, Copy)]
pub enum CurvatureEstimationMethod {
DiagonalHessian,
BlockDiagonalHessian,
KroneckerFactored,
NaturalGradient,
}
#[derive(Debug)]
pub struct MixedModeAD<T: Float + Debug + Send + Sync + 'static> {
forward_component: ForwardModeAD<T>,
reverse_component: ReverseModeAD<T>,
mode_selection: ModeSelectionStrategy,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> MixedModeAD<T> {
pub fn new() -> Result<Self> {
Ok(Self {
forward_component: ForwardModeAD::new()?,
reverse_component: ReverseModeAD::new()?,
mode_selection: ModeSelectionStrategy::Adaptive,
})
}
}
#[derive(Debug, Clone)]
pub struct AdaptationStatistics<T: Float + Debug + Send + Sync + 'static> {
pub convergence_steps: Vec<usize>,
pub final_losses: Vec<T>,
pub adaptation_efficiency: T,
pub stability_metrics: StabilityMetrics<T>,
}
#[derive(Debug, Clone)]
pub struct MetaValidationResult<T: Float + Debug + Send + Sync + 'static> {
pub performance: T,
pub adaptation_speed: T,
pub generalization_gap: T,
pub task_specific_metrics: HashMap<String, T>,
}
#[derive(Debug, Clone, Copy)]
pub enum LossFunction {
MeanSquaredError,
CrossEntropy,
Hinge,
Huber,
}
pub struct AdaptationEngine<T: Float + Debug + Send + Sync + 'static> {
config: MetaLearningConfig,
_phantom: std::marker::PhantomData<T>,
}
impl<T: Float + Debug + Send + Sync + 'static + Default + Clone> AdaptationEngine<T> {
pub fn new(config: &MetaLearningConfig) -> Result<Self> {
Ok(Self {
config: config.clone(),
_phantom: std::marker::PhantomData,
})
}
pub fn adapt(
&mut self,
task: &MetaTask<T>,
_meta_parameters: &HashMap<String, Array1<T>>,
_meta_learner: &mut dyn MetaLearner<T>,
_inner_steps: usize,
) -> Result<TaskAdaptationResult<T>> {
Ok(TaskAdaptationResult {
adapted_parameters: _meta_parameters.clone(),
adaptation_trajectory: Vec::new(),
final_loss: T::from(0.1).unwrap_or_default(),
metrics: TaskAdaptationMetrics {
convergence_speed: T::from(1.0).unwrap_or_default(),
final_performance: T::from(0.9).unwrap_or_default(),
efficiency: T::from(0.8).unwrap_or_default(),
robustness: T::from(0.85).unwrap_or_default(),
},
})
}
}
#[derive(Debug, Clone)]
pub struct ContinualLearningSettings {
pub anti_forgetting_strategies: Vec<AntiForgettingStrategy>,
pub memory_replay: MemoryReplaySettings,
pub task_identification: TaskIdentificationMethod,
pub plasticity_stability_balance: f64,
}
#[derive(Debug, Clone, Copy)]
pub enum TaskWeightingStrategy {
Uniform,
UncertaintyBased,
GradientMagnitude,
PerformanceBased,
Adaptive,
Learned,
}
#[derive(Debug, Clone)]
pub struct MultiTaskSettings {
pub task_weighting: TaskWeightingStrategy,
pub gradient_balancing: GradientBalancingMethod,
pub interference_mitigation: InterferenceMitigationStrategy,
pub shared_representation: SharedRepresentationStrategy,
}
#[derive(Debug, Clone, Copy)]
pub enum SharedRepresentationStrategy {
HardSharing,
SoftSharing,
HierarchicalSharing,
AttentionBased,
Modular,
}
#[derive(Debug, Clone, Copy)]
pub enum DistanceMetric {
Euclidean,
Cosine,
Mahalanobis,
Learned,
}
#[derive(Debug, Clone)]
pub struct DualNumber<T: Float + Debug + Send + Sync + 'static> {
pub real: T,
pub dual: T,
}
#[derive(Debug, Clone)]
pub struct TaskAdaptationMetrics<T: Float + Debug + Send + Sync + 'static> {
pub convergence_speed: T,
pub final_performance: T,
pub efficiency: T,
pub robustness: T,
}
#[derive(Debug, Clone, Copy)]
pub enum ModeSelectionStrategy {
ForwardOnly,
ReverseOnly,
Adaptive,
Hybrid,
}
#[derive(Debug, Clone)]
pub struct FewShotSettings {
pub num_shots: usize,
pub num_ways: usize,
pub algorithm: FewShotAlgorithm,
pub metric_learning: MetricLearningSettings,
pub augmentation_strategies: Vec<AugmentationStrategy>,
}
#[derive(Debug, Clone, Copy)]
pub enum SimilarityMeasure {
CosineDistance,
KLDivergence,
WassersteinDistance,
CentralMomentDiscrepancy,
MaximumMeanDiscrepancy,
}
#[derive(Debug, Clone)]
pub enum ComputationOperation<T: Float + Debug + Send + Sync + 'static> {
Add,
Multiply,
MatMul(Array2<T>),
Activation(ActivationFunction),
Loss(LossFunction),
Parameter(Array1<T>),
Input,
}
#[derive(Debug, Clone)]
pub struct MetaLearningConfig {
pub algorithm: MetaLearningAlgorithm,
pub inner_steps: usize,
pub outer_steps: usize,
pub meta_learning_rate: f64,
pub inner_learning_rate: f64,
pub task_batch_size: usize,
pub support_set_size: usize,
pub query_set_size: usize,
pub second_order: bool,
pub gradient_clip: f64,
pub adaptation_strategies: Vec<AdaptationStrategy>,
pub transfer_settings: TransferLearningSettings,
pub continual_settings: ContinualLearningSettings,
pub multitask_settings: MultiTaskSettings,
pub few_shot_settings: FewShotSettings,
pub enable_meta_regularization: bool,
pub meta_regularization_strength: f64,
pub task_sampling_strategy: TaskSamplingStrategy,
}
#[derive(Debug, Clone, Copy)]
pub enum TaskSamplingStrategy {
Uniform,
Curriculum,
DifficultyBased,
DiversityBased,
ActiveLearning,
Adversarial,
}
#[derive(Debug, Clone)]
pub struct FewShotResult<T: Float + Debug + Send + Sync + 'static> {
pub accuracy: T,
pub confidence: T,
pub adaptation_steps: usize,
pub uncertainty_estimates: Vec<T>,
}