qop-text.py

from qiskit import QuantumCircuit, Aer, execute
from qiskit.quantum_info import Statevector
import numpy as np

class QuantumFilter:
    def __init__(self, num_qubits):
        self.num_qubits = num_qubits
        self.circuit = QuantumCircuit(num_qubits)

    def grovers_algorithm(self, oracle):
        # Implement Grover's algorithm to find the desired state
        self.circuit.h(range(self.num_qubits))
        self.circuit.barrier()

        iterations = int(np.pi / 4 * np.sqrt(2 ** self.num_qubits))
        for _ in range(iterations):
            oracle(self.circuit)
            self.diffusion_operator()

        self.circuit.barrier()

    def diffusion_operator(self):
        self.circuit.h(range(self.num_qubits))
        self.circuit.x(range(self.num_qubits))
        self.circuit.h(self.num_qubits - 1)
        self.circuit.mct(list(range(self.num_qubits - 1)), self.num_qubits - 1)
        self.circuit.h(self.num_qubits - 1)
        self.circuit.x(range(self.num_qubits))
        self.circuit.h(range(self.num_qubits))

    def shors_algorithm(self, a, N):
        # Implement Shor's algorithm to factorize a number
        self.circuit.h(range(self.num_qubits))
        self.circuit.barrier()

        for qubit in range(self.num_qubits):
            self.circuit.u1(2 * np.pi * a**(2**qubit) / N, qubit)

        self.circuit.barrier()
        self.circuit.qft(range(self.num_qubits))
        self.circuit.barrier()

    def apply_filter(self, input_state, oracle, a, N):
        # Apply the quantum filter to the input state
        self.grovers_algorithm(oracle)
        self.shors_algorithm(a, N)

        # Simulate the quantum circuit
        backend = Aer.get_backend('statevector_simulator')
        result = execute(self.circuit, backend).result()
        statevector = result.get_statevector()

        # Process the output statevector
        filtered_state = self.process_output(input_state, statevector)

        return filtered_state

    def process_output(self, input_state, statevector):
        # Process the output statevector and apply it to the input state
        output_state = input_state.copy()
        for i in range(len(input_state)):
            amplitude = statevector[i]
            output_state[i] *= amplitude

        return output_state

def oracle(circuit):
    # Define the oracle based on the desired state
    # Example: Mark the state |1010> as the desired state
    circuit.x(1)
    circuit.x(3)
    circuit.h(2)
    circuit.ccx(0, 1, 2)
    circuit.h(2)
    circuit.x(1)
    circuit.x(3)

def process_text(input_text, num_qubits, a, N):
    # Convert input text to a quantum state
    input_state = np.array([ord(char) for char in input_text])

    # Create quantum filter and apply it to the input state
    quantum_filter = QuantumFilter(num_qubits)
    filtered_state = quantum_filter.apply_filter(input_state, oracle, a, N)

    # Convert the filtered state back to text
    filtered_text = ''.join([chr(int(round(val))) for val in filtered_state])

    return filtered_text

# Example usage
input_text = "Hello, World!"
num_qubits = 4
a = 7
N = 15

filtered_text = process_text(input_text, num_qubits, a, N)
print(f"Original Text: {input_text}")
print(f"Filtered Text: {filtered_text}")