quantrs2_sim/advanced_variational_algorithms/
functions.rs1use crate::circuit_interfaces::{InterfaceCircuit, InterfaceGate, InterfaceGateType};
6use crate::error::{Result, SimulatorError};
7use scirs2_core::random::prelude::*;
8use scirs2_core::Complex64;
9use std::collections::{HashMap, VecDeque};
10use std::time::{Duration, Instant};
11
12use super::types::{
13 AdvancedOptimizerType, AdvancedVQATrainer, FiniteDifferenceGradient, HamiltonianTerm,
14 IsingCostFunction, MixerHamiltonian, MixerType, OptimizationProblemType,
15 ParameterShiftGradient, ProblemHamiltonian, VQAConfig, VariationalAnsatz,
16};
17
18pub trait CostFunction: Send + Sync {
20 fn evaluate(&self, parameters: &[f64], circuit: &InterfaceCircuit) -> Result<f64>;
22 fn get_observables(&self) -> Vec<String>;
24 fn is_variational(&self) -> bool;
26}
27pub trait GradientCalculator: Send + Sync {
29 fn calculate_gradient(
31 &self,
32 parameters: &[f64],
33 cost_function: &dyn CostFunction,
34 circuit: &InterfaceCircuit,
35 ) -> Result<Vec<f64>>;
36 fn method_name(&self) -> &str;
38}
39pub fn benchmark_advanced_vqa() -> Result<HashMap<String, f64>> {
41 let mut results = HashMap::new();
42 let start = Instant::now();
43 let ansatz = VariationalAnsatz::HardwareEfficient {
44 layers: 3,
45 entangling_gates: vec![InterfaceGateType::CNOT],
46 rotation_gates: vec![InterfaceGateType::RY(0.0)],
47 };
48 let config = VQAConfig::default();
49 let cost_function = Box::new(IsingCostFunction {
50 problem_hamiltonian: ProblemHamiltonian {
51 terms: vec![HamiltonianTerm {
52 coefficient: Complex64::new(-1.0, 0.0),
53 pauli_string: "ZZ".to_string(),
54 qubits: vec![0, 1],
55 }],
56 problem_type: OptimizationProblemType::MaxCut,
57 },
58 });
59 let gradient_calculator = Box::new(FiniteDifferenceGradient { epsilon: 1e-4 });
60 let mut trainer = AdvancedVQATrainer::new(config, ansatz, cost_function, gradient_calculator)?;
61 let _result = trainer.train()?;
62 let hardware_efficient_time = start.elapsed().as_millis() as f64;
63 results.insert(
64 "hardware_efficient_vqa".to_string(),
65 hardware_efficient_time,
66 );
67 Ok(results)
68}
69#[cfg(test)]
70mod tests {
71 use super::*;
72 #[test]
73 fn test_vqa_trainer_creation() {
74 let ansatz = VariationalAnsatz::HardwareEfficient {
75 layers: 2,
76 entangling_gates: vec![InterfaceGateType::CNOT],
77 rotation_gates: vec![InterfaceGateType::RY(0.0)],
78 };
79 let config = VQAConfig::default();
80 let cost_function = Box::new(IsingCostFunction {
81 problem_hamiltonian: ProblemHamiltonian {
82 terms: vec![],
83 problem_type: OptimizationProblemType::MaxCut,
84 },
85 });
86 let gradient_calculator = Box::new(FiniteDifferenceGradient { epsilon: 1e-4 });
87 let trainer = AdvancedVQATrainer::new(config, ansatz, cost_function, gradient_calculator);
88 assert!(trainer.is_ok());
89 }
90 #[test]
91 fn test_parameter_counting() {
92 let ansatz = VariationalAnsatz::HardwareEfficient {
93 layers: 3,
94 entangling_gates: vec![InterfaceGateType::CNOT],
95 rotation_gates: vec![InterfaceGateType::RY(0.0)],
96 };
97 let count =
98 AdvancedVQATrainer::count_parameters(&ansatz).expect("Failed to count parameters");
99 assert!(count > 0);
100 }
101 #[test]
102 fn test_uccsd_ansatz() {
103 let ansatz = VariationalAnsatz::UCCSD {
104 num_electrons: 2,
105 num_orbitals: 4,
106 include_triples: false,
107 };
108 let count = AdvancedVQATrainer::count_parameters(&ansatz)
109 .expect("Failed to count UCCSD parameters");
110 assert!(count > 0);
111 }
112 #[test]
113 fn test_qaoa_ansatz() {
114 let ansatz = VariationalAnsatz::QAOA {
115 problem_hamiltonian: ProblemHamiltonian {
116 terms: vec![],
117 problem_type: OptimizationProblemType::MaxCut,
118 },
119 mixer_hamiltonian: MixerHamiltonian {
120 terms: vec![],
121 mixer_type: MixerType::XMixer,
122 },
123 layers: 3,
124 };
125 let count =
126 AdvancedVQATrainer::count_parameters(&ansatz).expect("Failed to count QAOA parameters");
127 assert_eq!(count, 6);
128 }
129 #[test]
130 fn test_finite_difference_gradient() {
131 let gradient_calc = FiniteDifferenceGradient { epsilon: 1e-4 };
132 assert_eq!(gradient_calc.method_name(), "FiniteDifference");
133 }
134 #[test]
135 fn test_parameter_shift_gradient() {
136 let gradient_calc = ParameterShiftGradient;
137 assert_eq!(gradient_calc.method_name(), "ParameterShift");
138 }
139 #[test]
140 fn test_ising_cost_function() {
141 let cost_function = IsingCostFunction {
142 problem_hamiltonian: ProblemHamiltonian {
143 terms: vec![HamiltonianTerm {
144 coefficient: Complex64::new(-1.0, 0.0),
145 pauli_string: "ZZ".to_string(),
146 qubits: vec![0, 1],
147 }],
148 problem_type: OptimizationProblemType::MaxCut,
149 },
150 };
151 assert!(cost_function.is_variational());
152 assert!(!cost_function.get_observables().is_empty());
153 }
154 #[test]
155 fn test_optimizer_types() {
156 let optimizers = [
157 AdvancedOptimizerType::SPSA,
158 AdvancedOptimizerType::QuantumAdam,
159 AdvancedOptimizerType::NaturalGradient,
160 AdvancedOptimizerType::BayesianOptimization,
161 ];
162 for optimizer in &optimizers {
163 println!("Testing optimizer: {optimizer:?}");
164 }
165 }
166}