app.py

import gradio as gr
from qiskit import QuantumCircuit, transpile
from qiskit_aer import Aer
from qiskit.visualization import plot_histogram
import matplotlib.pyplot as plt
import ast

def apply_cnot(initial_state_str):
    # Convert input string to actual Python list
    initial_state = ast.literal_eval(initial_state_str)

    # Create Quantum Circuit
    qc = QuantumCircuit(2, 2)
    qc.initialize(initial_state, [0, 1])
    qc.cx(0, 1)
    qc.measure([0, 1], [0, 1])
    
    # Simulation
    simulator = Aer.get_backend('qasm_simulator')
    transpiled_circuit = transpile(qc, simulator)
    result = simulator.run(transpiled_circuit, shots=1024).result()
    counts = result.get_counts()
    
    # Plot results
    fig, ax = plt.subplots()
    plot_histogram(counts, ax=ax)
    return fig

# Gradio Interface
interface = gr.Interface(
    fn=apply_cnot,
    inputs=gr.Radio(["[1,0,0,0]", "[0,1,0,0]", "[0,0,1,0]", "[0,0,0,1]"], label="Initial State"),
    outputs=gr.Plot(),
    title="Quantum CNOT Gate Simulation",
    description="Select an initial state to apply a CNOT gate in a quantum circuit and view the measurement results."
)

if __name__ == "__main__":
    interface.launch()