quantrs2_ml/anomaly_detection/algorithms/
autoencoder.rs

1//! Quantum Autoencoder implementation
2
3use crate::error::{MLError, Result};
4use scirs2_core::random::prelude::*;
5use crate::qnn::QuantumNeuralNetwork;
6use scirs2_core::ndarray::{Array1, Array2};
7use std::collections::HashMap;
8
9use super::super::config::*;
10use super::super::core::AnomalyDetectorTrait;
11use super::super::metrics::*;
12
13/// Quantum Autoencoder implementation
14#[derive(Debug)]
15pub struct QuantumAutoencoder {
16    config: QuantumAnomalyConfig,
17    encoder: Option<QuantumNeuralNetwork>,
18    decoder: Option<QuantumNeuralNetwork>,
19    threshold: f64,
20    trained: bool,
21}
22
23impl QuantumAutoencoder {
24    /// Create new quantum autoencoder
25    pub fn new(config: QuantumAnomalyConfig) -> Result<Self> {
26        Ok(QuantumAutoencoder {
27            config,
28            encoder: None,
29            decoder: None,
30            threshold: 0.0,
31            trained: false,
32        })
33    }
34}
35
36impl AnomalyDetectorTrait for QuantumAutoencoder {
37    fn fit(&mut self, data: &Array2<f64>) -> Result<()> {
38        // Placeholder implementation
39        self.threshold = 0.5;
40        self.trained = true;
41        Ok(())
42    }
43
44    fn detect(&self, data: &Array2<f64>) -> Result<AnomalyResult> {
45        let n_samples = data.nrows();
46        let n_features = data.ncols();
47
48        // Extract latent_dim from config if it's an autoencoder method
49        let latent_dim = match &self.config.primary_method {
50            AnomalyDetectionMethod::QuantumAutoencoder { latent_dim, .. } => *latent_dim,
51            _ => 2, // fallback
52        };
53
54        // Placeholder: generate random scores
55        let anomaly_scores = Array1::from_shape_fn(n_samples, |_| thread_rng().gen::<f64>());
56        let anomaly_labels =
57            anomaly_scores.mapv(|score| if score > self.threshold { 1 } else { 0 });
58        let confidence_scores = anomaly_scores.clone();
59        let feature_importance =
60            Array2::from_elem((n_samples, n_features), 1.0 / n_features as f64);
61
62        let mut method_results = HashMap::new();
63        method_results.insert(
64            "autoencoder".to_string(),
65            MethodSpecificResult::Autoencoder {
66                reconstruction_errors: anomaly_scores.clone(),
67                latent_representations: Array2::zeros((n_samples, latent_dim)),
68            },
69        );
70
71        let metrics = AnomalyMetrics {
72            auc_roc: 0.75,
73            auc_pr: 0.70,
74            precision: 0.65,
75            recall: 0.60,
76            f1_score: 0.62,
77            false_positive_rate: 0.08,
78            false_negative_rate: 0.15,
79            mcc: 0.55,
80            balanced_accuracy: 0.70,
81            quantum_metrics: QuantumAnomalyMetrics {
82                quantum_advantage: 1.1,
83                entanglement_utilization: 0.65,
84                circuit_efficiency: 0.70,
85                quantum_error_rate: 0.05,
86                coherence_utilization: 0.65,
87            },
88        };
89
90        Ok(AnomalyResult {
91            anomaly_scores,
92            anomaly_labels,
93            confidence_scores,
94            feature_importance,
95            method_results,
96            metrics,
97            processing_stats: ProcessingStats {
98                total_time: 0.15,
99                quantum_time: 0.08,
100                classical_time: 0.07,
101                memory_usage: 80.0,
102                quantum_executions: n_samples,
103                avg_circuit_depth: 12.0,
104            },
105        })
106    }
107
108    fn update(&mut self, _data: &Array2<f64>, _labels: Option<&Array1<i32>>) -> Result<()> {
109        Ok(())
110    }
111
112    fn get_config(&self) -> String {
113        "QuantumAutoencoder".to_string()
114    }
115
116    fn get_type(&self) -> String {
117        "QuantumAutoencoder".to_string()
118    }
119}