qiskit.aqua.algorithms.Shor
class Shor(N=15, a=2, quantum_instance=None)
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 in polynomial time.
The input integer 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 can also be supplied, which needs to be a co-prime smaller than .
Adapted from https://github.com/ttlion/ShorAlgQiskit
See also https://arxiv.org/abs/quant-ph/0205095
Parameters
-
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. -
quantum_instance (
Union[QuantumInstance,Backend,BaseBackend,None]) –Quantum Instance or Backend
Raises:
ValueError: Invalid input
__init__
__init__(N=15, a=2, quantum_instance=None)
Parameters
-
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. -
quantum_instance (
Union[QuantumInstance,Backend,BaseBackend,None]) –Quantum Instance or Backend
Raises:
ValueError: Invalid input
Methods
__init__([N, a, quantum_instance]) | type Nint |
construct_circuit([measurement]) | Construct circuit. |
modinv(a, m) | Returns the modular multiplicative inverse of a with respect to the modulus m. |
run([quantum_instance]) | Execute the algorithm with selected backend. |
set_backend(backend, **kwargs) | Sets backend with configuration. |
Attributes
backend | Returns backend. |
quantum_instance | Returns quantum instance. |
random | Return a numpy random. |
backend
Returns backend.
Return type
Union[Backend, BaseBackend]
construct_circuit
construct_circuit(measurement=False)
Construct circuit.
Parameters
measurement (bool) – Boolean flag to indicate if measurement should be included in the circuit.
Return type
QuantumCircuit
Returns
Quantum circuit.
modinv
static modinv(a, m)
Returns the modular multiplicative inverse of a with respect to the modulus m.
Return type
int
quantum_instance
Returns quantum instance.
Return type
Optional[QuantumInstance]
random
Return a numpy random.
run
run(quantum_instance=None, **kwargs)
Execute the algorithm with selected backend.
Parameters
- quantum_instance (
Union[QuantumInstance,Backend,BaseBackend,None]) – the experimental setting. - kwargs (dict) – kwargs
Returns
results of an algorithm.
Return type
dict
Raises
AquaError – If a quantum instance or backend has not been provided
set_backend
set_backend(backend, **kwargs)
Sets backend with configuration.
Return type
None