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* pre-commit: Upgrade psf/black for stable style 2023 Updating https://github.com/psf/black ... updating 22.12.0 -> 23.1.0 for their `2023 stable style`. * https://github.com/psf/black/blob/main/CHANGES.md#2310 > This is the first [psf/black] release of 2023, and following our stability policy, it comes with a number of improvements to our stable style… Also, add https://github.com/tox-dev/pyproject-fmt and https://github.com/abravalheri/validate-pyproject to pre-commit. I only modified `.pre-commit-config.yaml` and all other files were modified by pre-commit.ci and psf/black. * [pre-commit.ci] auto fixes from pre-commit.com hooks for more information, see https://pre-commit.ci --------- Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
97 lines
3.6 KiB
Python
97 lines
3.6 KiB
Python
"""
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Build the quantum fourier transform (qft) for a desire
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number of quantum bits using Qiskit framework. This
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experiment run in IBM Q simulator with 10000 shots.
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This circuit can be use as a building block to design
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the Shor's algorithm in quantum computing. As well as,
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quantum phase estimation among others.
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.
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References:
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https://en.wikipedia.org/wiki/Quantum_Fourier_transform
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https://qiskit.org/textbook/ch-algorithms/quantum-fourier-transform.html
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"""
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import math
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import numpy as np
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import qiskit
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from qiskit import Aer, ClassicalRegister, QuantumCircuit, QuantumRegister, execute
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def quantum_fourier_transform(number_of_qubits: int = 3) -> qiskit.result.counts.Counts:
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"""
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# >>> quantum_fourier_transform(2)
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# {'00': 2500, '01': 2500, '11': 2500, '10': 2500}
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# quantum circuit for number_of_qubits = 3:
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┌───┐
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qr_0: ──────■──────────────────────■───────┤ H ├─X─
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│ ┌───┐ │P(π/2) └───┘ │
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qr_1: ──────┼────────■───────┤ H ├─■─────────────┼─
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┌───┐ │P(π/4) │P(π/2) └───┘ │
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qr_2: ┤ H ├─■────────■───────────────────────────X─
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└───┘
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cr: 3/═════════════════════════════════════════════
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Args:
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n : number of qubits
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Returns:
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qiskit.result.counts.Counts: distribute counts.
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>>> quantum_fourier_transform(2)
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{'00': 2500, '01': 2500, '10': 2500, '11': 2500}
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>>> quantum_fourier_transform(-1)
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Traceback (most recent call last):
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...
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ValueError: number of qubits must be > 0.
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>>> quantum_fourier_transform('a')
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Traceback (most recent call last):
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...
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TypeError: number of qubits must be a integer.
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>>> quantum_fourier_transform(100)
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Traceback (most recent call last):
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...
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ValueError: number of qubits too large to simulate(>10).
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>>> quantum_fourier_transform(0.5)
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Traceback (most recent call last):
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...
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ValueError: number of qubits must be exact integer.
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"""
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if isinstance(number_of_qubits, str):
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raise TypeError("number of qubits must be a integer.")
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if number_of_qubits <= 0:
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raise ValueError("number of qubits must be > 0.")
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if math.floor(number_of_qubits) != number_of_qubits:
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raise ValueError("number of qubits must be exact integer.")
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if number_of_qubits > 10:
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raise ValueError("number of qubits too large to simulate(>10).")
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qr = QuantumRegister(number_of_qubits, "qr")
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cr = ClassicalRegister(number_of_qubits, "cr")
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quantum_circuit = QuantumCircuit(qr, cr)
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counter = number_of_qubits
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for i in range(counter):
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quantum_circuit.h(number_of_qubits - i - 1)
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counter -= 1
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for j in range(counter):
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quantum_circuit.cp(np.pi / 2 ** (counter - j), j, counter)
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for k in range(number_of_qubits // 2):
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quantum_circuit.swap(k, number_of_qubits - k - 1)
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# measure all the qubits
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quantum_circuit.measure(qr, cr)
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# simulate with 10000 shots
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backend = Aer.get_backend("qasm_simulator")
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job = execute(quantum_circuit, backend, shots=10000)
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return job.result().get_counts(quantum_circuit)
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if __name__ == "__main__":
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print(
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f"Total count for quantum fourier transform state is: \
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{quantum_fourier_transform(3)}"
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)
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