qiskit.algorithms.Shor¶

class Shor(quantum_instance=None)[ソース]¶

Shor’s factoring algorithm.

Shor’s Factoring algorithm is one of the most well-known quantum algorithms and finds the prime factors for input integer \(N\) in polynomial time.

Adapted from https://github.com/ttlion/ShorAlgQiskit

パラメータ: quantum_instance (Union[QuantumInstance, BaseBackend, Backend, None]) – Quantum Instance or Backend

__init__(quantum_instance=None)[ソース]¶

パラメータ: quantum_instance (Union[QuantumInstance, BaseBackend, Backend, None]) – Quantum Instance or Backend

Methods

`__init__`([quantum_instance])	type quantum_instance `Union`[`QuantumInstance`, `BaseBackend`, `Backend`, `None`]
`construct_circuit`(N[, a, measurement])	Construct circuit.
`factor`(N[, a])	Execute the algorithm.
`modinv`(a, m)	Returns the modular multiplicative inverse of a with respect to the modulus m.

Attributes

quantum_instance

Returns quantum instance.

construct_circuit(N, a=2, measurement=False)[ソース]¶

Construct circuit.

パラメータ

N (int) – The integer to be factored, has a min. value of 3.
a (int) – Any integer that satisfies 1 < a < N and gcd(a, N) = 1.
measurement (bool) – Boolean flag to indicate if measurement should be included in the circuit.

戻り値の型

QuantumCircuit

戻り値

Quantum circuit.

例外

ValueError – Invalid N

factor(N, a=2)[ソース]¶

Execute the algorithm.

The input integer \(N\) to be factored is expected to be odd and greater than 2. Even though this implementation is general, its capability will be limited by the capacity of the simulator/hardware. Another input integer \(a\) can also be supplied, which needs to be a co-prime smaller than \(N\) .

パラメータ

N (int) – The integer to be factored, has a min. value of 3.
a (int) – Any integer that satisfies 1 < a < N and gcd(a, N) = 1.

戻り値

results of the algorithm.

戻り値の型

ShorResult

例外

ValueError – Invalid input
AlgorithmError – If a quantum instance or backend has not been provided

static modinv(a, m)[ソース]¶

Returns the modular multiplicative inverse of a with respect to the modulus m.

戻り値の型: int

property quantum_instance¶

Returns quantum instance.

戻り値の型: Optional[QuantumInstance]