Source code for qlauncher.routines.qiskit.algorithms.shor

 1import numpy as np
 2from qiskit import ClassicalRegister, QuantumCircuit, QuantumRegister
 3from qiskit.circuit.library import QFTGate
 4
 5from qlauncher.base import Algorithm, Result
 6from qlauncher.base.models import ShorCircuit
 7from qlauncher.routines.qiskit.backends.qiskit_backend import QiskitBackend
 8
 9

[docs]
10class Shor(Algorithm[ShorCircuit, QiskitBackend]):
11    def __init__(self, n_shots: int, **alg_kwargs):
12        super().__init__(**alg_kwargs)
13        self.n_shots = n_shots
14

[docs]
15    def run(self, problem: ShorCircuit, backend: QiskitBackend) -> Result:
16        n_qubits = problem.n_phase_kickback_qubits
17        phase_kickback = QuantumRegister(n_qubits, 'phase')
18        eigen_state = QuantumRegister(problem.num_qubits - 1, 'eigen')
19        classical_reg = ClassicalRegister(n_qubits, 'creg')
20
21        qft = QFTGate(num_qubits=n_qubits)
22        qft_i = qft.inverse()
23
24        full_circuit = QuantumCircuit(phase_kickback, eigen_state, classical_reg)
25
26        if not problem.eigen_state_prep:
27            full_circuit.x(eigen_state[0])
28        else:
29            full_circuit.append(problem.eigen_state_prep, eigen_state[: problem.eigen_state_prep.num_qubits])
30
31        full_circuit.h(phase_kickback)
32
33        for qubit_ix in range(n_qubits):
34            full_circuit.append(
35                problem.gates[n_qubits - qubit_ix - 1],
36                [phase_kickback[n_qubits - qubit_ix - 1]] + eigen_state[: problem.gates[qubit_ix].num_qubits],
37            )
38
39        full_circuit.append(qft_i, phase_kickback)
40
41        full_circuit.measure(phase_kickback, classical_reg)
42
43        job = backend.sampler.run([full_circuit], shots=self.n_shots)
44
45        return job.result()[0]