oxicuda_quantum/
lib.rs

1//! Quantum simulation primitives for OxiCUDA.
2//!
3//! Provides state-vector simulation, Pauli expectation values, VQE/QAOA,
4//! density matrices, Trotter-Suzuki time evolution, quantum kernels, and
5//! PTX kernel code generation for GPU execution.
6
7pub mod channel;
8pub mod circuit;
9pub mod density;
10pub mod embedding;
11pub mod error;
12pub mod gates;
13pub mod handle;
14pub mod kernel;
15pub mod midcircuit;
16pub mod mps;
17pub mod pauli;
18pub mod ptx_kernels;
19pub mod qaoa;
20pub mod stabilizer;
21pub mod statevec;
22pub mod trotter;
23pub mod vqe;
24
25pub use error::{QuantumError, QuantumResult};
26pub use midcircuit::{
27    ClassicalRegister, MidCircuitOp, apply_if, measure_and_collapse, measure_deterministic,
28    run as run_midcircuit,
29};
30pub use mps::{MatrixProductState, MpsConfig};
31
32#[cfg(test)]
33mod e2e_tests {
34    use crate::channel::noise::{amplitude_damping_channel, depolarizing_channel};
35    use crate::circuit::circuit::{GateOp, QuantumCircuit};
36    use crate::density::density::DensityMatrix;
37    use crate::density::metrics::purity;
38    use crate::gates::controlled::apply_cnot;
39    use crate::gates::hadamard::gate_h;
40    use crate::gates::pauli::gate_x;
41    use crate::handle::LcgRng;
42    use crate::pauli::expval::expectation_value;
43    use crate::pauli::hamiltonian::Hamiltonian;
44    use crate::pauli::pauli_string::PauliOp;
45    use crate::ptx_kernels::{
46        expval_pauli_ptx, measure_prob_ptx, partial_trace_ptx, statevec_apply_1q_ptx,
47        statevec_apply_2q_ptx, statevec_apply_cnot_ptx, trotter_step_ptx,
48    };
49    use crate::qaoa::qaoa::QaoaCircuit;
50    use crate::statevec::apply_1q::apply_1q_inplace;
51    use crate::statevec::state::StateVector;
52    use crate::vqe::ansatz::HardwareEfficientAnsatz;
53    use crate::vqe::vqe::VqeOptimizer;
54
55    // Test 1: |0⟩ state has norm 1
56    #[test]
57    fn e2e_01_zero_state_norm_is_one() {
58        let sv = StateVector::new_zero_state(3).unwrap();
59        let norm = sv.norm_sq();
60        assert!((norm - 1.0).abs() < 1e-6, "norm={norm}");
61    }
62
63    // Test 2: H gate on |0⟩ gives equal superposition
64    #[test]
65    fn e2e_02_hadamard_creates_superposition() {
66        let mut sv = StateVector::new_zero_state(1).unwrap();
67        apply_1q_inplace(&mut sv, 0, &gate_h()).unwrap();
68        let inv_sqrt2 = std::f32::consts::FRAC_1_SQRT_2;
69        assert!(
70            (sv.amps[0].re - inv_sqrt2).abs() < 1e-5,
71            "amp0={:?}",
72            sv.amps[0]
73        );
74        assert!(
75            (sv.amps[1].re - inv_sqrt2).abs() < 1e-5,
76            "amp1={:?}",
77            sv.amps[1]
78        );
79    }
80
81    // Test 3: H·H = I (round-trip)
82    #[test]
83    fn e2e_03_hadamard_round_trip() {
84        let mut sv = StateVector::new_zero_state(1).unwrap();
85        apply_1q_inplace(&mut sv, 0, &gate_h()).unwrap();
86        apply_1q_inplace(&mut sv, 0, &gate_h()).unwrap();
87        assert!((sv.amps[0].re - 1.0).abs() < 1e-5, "amp0={:?}", sv.amps[0]);
88        assert!(sv.amps[1].norm() < 1e-5, "amp1={:?}", sv.amps[1]);
89    }
90
91    // Test 4: CNOT creates Bell state |00⟩+|11⟩/√2
92    #[test]
93    fn e2e_04_cnot_creates_bell_state() {
94        let mut sv = StateVector::new_zero_state(2).unwrap();
95        apply_1q_inplace(&mut sv, 0, &gate_h()).unwrap();
96        apply_cnot(&mut sv, 0, 1).unwrap();
97        let inv_sqrt2 = std::f32::consts::FRAC_1_SQRT_2;
98        // |00⟩ at index 0, |11⟩ at index 3
99        assert!((sv.amps[0].re - inv_sqrt2).abs() < 1e-5);
100        assert!((sv.amps[3].re - inv_sqrt2).abs() < 1e-5);
101        assert!(sv.amps[1].norm() < 1e-5);
102        assert!(sv.amps[2].norm() < 1e-5);
103    }
104
105    // Test 5: Pauli-Z expectation of |0⟩ = +1
106    #[test]
107    fn e2e_05_pauli_z_expval_zero_state() {
108        let sv = StateVector::new_zero_state(1).unwrap();
109        let mut ham = Hamiltonian::new();
110        ham.add_term(1.0, vec![PauliOp::Z]);
111        let ev = expectation_value(&sv, &ham).unwrap();
112        assert!((ev - 1.0).abs() < 1e-5, "ev={ev}");
113    }
114
115    // Test 6: Pauli-Z expectation of |1⟩ = -1
116    #[test]
117    fn e2e_06_pauli_z_expval_one_state() {
118        let mut sv = StateVector::new_zero_state(1).unwrap();
119        apply_1q_inplace(&mut sv, 0, &gate_x()).unwrap(); // flip to |1⟩
120        let mut ham = Hamiltonian::new();
121        ham.add_term(1.0, vec![PauliOp::Z]);
122        let ev = expectation_value(&sv, &ham).unwrap();
123        assert!((ev - (-1.0)).abs() < 1e-5, "ev={ev}");
124    }
125
126    // Test 7: Mixed Hamiltonian expectation value is finite
127    #[test]
128    fn e2e_07_mixed_hamiltonian_expval_finite() {
129        let mut sv = StateVector::new_zero_state(2).unwrap();
130        apply_1q_inplace(&mut sv, 0, &gate_h()).unwrap();
131        apply_cnot(&mut sv, 0, 1).unwrap();
132        let mut ham = Hamiltonian::new();
133        ham.add_term(0.5, vec![PauliOp::Z, PauliOp::Z]);
134        ham.add_term(0.3, vec![PauliOp::X, PauliOp::I]);
135        ham.add_term(0.2, vec![PauliOp::I, PauliOp::Y]);
136        let ev = expectation_value(&sv, &ham).unwrap();
137        assert!(ev.is_finite(), "ev={ev}");
138    }
139
140    // Test 8: VQE energy decreases over iterations
141    #[test]
142    fn e2e_08_vqe_energy_decreases() {
143        let ans = HardwareEfficientAnsatz::new(2, 1);
144        let mut ham = Hamiltonian::new();
145        ham.add_term(1.0, vec![PauliOp::Z, PauliOp::Z]);
146        ham.add_term(-0.5, vec![PauliOp::X, PauliOp::I]);
147        let mut rng = LcgRng::new(42);
148        let mut opt = VqeOptimizer::new(ans, ham, &mut rng);
149        let e_initial = opt.energy(&opt.params.clone()).unwrap();
150        let (e_final, _) = opt.optimize(5, 0.1).unwrap();
151        assert!(
152            e_final <= e_initial + 1e-3,
153            "e_initial={e_initial}, e_final={e_final}"
154        );
155    }
156
157    // Test 9: QAOA circuit runs without error
158    #[test]
159    fn e2e_09_qaoa_runs_without_error() {
160        let circuit = QaoaCircuit::new(4, 2, vec![0.3, 0.5], vec![0.7, 0.2]).unwrap();
161        let graph = vec![(0, 1), (1, 2), (2, 3), (3, 0)];
162        let sv = circuit.run(&graph).unwrap();
163        let norm = sv.norm_sq();
164        assert!((norm - 1.0).abs() < 1e-4, "norm={norm}");
165    }
166
167    // Test 10: Density matrix from pure state has purity 1
168    #[test]
169    fn e2e_10_pure_state_purity_is_one() {
170        let sv = StateVector::new_zero_state(2).unwrap();
171        let dm = DensityMatrix::from_pure_state(&sv);
172        let p = purity(&dm);
173        assert!((p - 1.0).abs() < 1e-5, "purity={p}");
174    }
175
176    // Test 11: Depolarizing channel reduces purity
177    #[test]
178    fn e2e_11_depolarizing_channel_reduces_purity() {
179        let sv = StateVector::new_zero_state(1).unwrap();
180        let dm = DensityMatrix::from_pure_state(&sv);
181        let p_initial = purity(&dm);
182
183        let ch = depolarizing_channel(0.5, 2).unwrap();
184        let dm_out = ch.apply(&dm).unwrap();
185        let p_final = purity(&dm_out);
186
187        assert!(
188            p_final < p_initial,
189            "purity did not decrease: {p_initial} → {p_final}"
190        );
191    }
192
193    // Test 12: PTX kernels generate non-empty strings for all 6 SM versions
194    #[test]
195    fn e2e_12_ptx_kernels_non_empty_all_sm() {
196        for sm in [75u32, 80, 86, 89, 90, 100] {
197            let s1 = statevec_apply_1q_ptx(sm);
198            let s2 = statevec_apply_2q_ptx(sm);
199            let s3 = statevec_apply_cnot_ptx(sm);
200            let s4 = expval_pauli_ptx(sm);
201            let s5 = partial_trace_ptx(sm);
202            let s6 = trotter_step_ptx(sm);
203            let s7 = measure_prob_ptx(sm);
204            assert!(!s1.is_empty(), "statevec_apply_1q sm={sm}");
205            assert!(!s2.is_empty(), "statevec_apply_2q sm={sm}");
206            assert!(!s3.is_empty(), "statevec_apply_cnot sm={sm}");
207            assert!(!s4.is_empty(), "expval_pauli sm={sm}");
208            assert!(!s5.is_empty(), "partial_trace sm={sm}");
209            assert!(!s6.is_empty(), "trotter_step sm={sm}");
210            assert!(!s7.is_empty(), "measure_prob sm={sm}");
211        }
212    }
213
214    // Supplementary: amplitude damping channel test
215    #[test]
216    fn e2e_13_amplitude_damping_channel() {
217        let sv = StateVector::new_zero_state(1).unwrap();
218        let dm = DensityMatrix::from_pure_state(&sv);
219        let ch = amplitude_damping_channel(0.3).unwrap();
220        let dm_out = ch.apply(&dm).unwrap();
221        let tr = dm_out.trace();
222        assert!((tr.re - 1.0).abs() < 1e-5, "trace={}", tr.re);
223    }
224
225    // Supplementary: circuit with explicit CNOTs
226    #[test]
227    fn e2e_14_circuit_bell_state() {
228        let mut circ = QuantumCircuit::new(2);
229        circ.add_gate(GateOp::H);
230        circ.add_gate(GateOp::Cnot { ctrl: 0, tgt: 1 });
231        let sv = StateVector::new_zero_state(2).unwrap();
232        let mut rng = LcgRng::new(7);
233        let out = circ.exec_on_state(&sv, &mut rng).unwrap();
234        let inv_sqrt2 = std::f32::consts::FRAC_1_SQRT_2;
235        assert!((out.amps[0].re - inv_sqrt2).abs() < 1e-5);
236        assert!((out.amps[3].re - inv_sqrt2).abs() < 1e-5);
237    }
238}
oxicuda_quantum/lib.rs

oxicuda_quantum/
lib.rs
