pyqubit 0.3.1

A lightweight quantum qubit simulator in Python

PyQubit v0.3 (first version)

A simple and intuitive Python class for single-qubit simulation.

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Installation

pip install pyqubit

Quick Start

from pyqubit import Qubit

q = Qubit(1, 0)
print(q)
q.hadamard()
print(q.probabilities())

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✨ Features

• Qubit State Management: Initialize a qubit in any valid superposition of the ∣0⟩ and ∣1⟩ states.
• State Normalization: Automatically ensures the qubit's state vector remains valid after every operation.
• Measurement Simulation: Collapse the qubit's state to a classical bit (0 or 1) based on its quantum probabilities.
• Standard Single-Qubit Gates:
  • Pauli-X (NOT)
  • Pauli-Y
  • Pauli-Z
  • Hadamard
  • Phase (S)
  • Phase (T)
• Parametrized Rotation Gates:
  • Rotation around X-axis (rX)
  • Rotation around Y-axis (rY)
  • Rotation around Z-axis (rZ)
• Probability Inspection: Easily retrieve the probabilities of measuring the qubit in the ∣0⟩ or ∣1⟩ state.

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🧩 Installation

Currently, you can use PyQubit by including the qubit.py file directly in your project.

# (Future installation via pip)
# pip install pyqubit

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🚀 Usage Guide

1. Import the Class

Save the file as qubit.py, then:

from qubit import Qubit
import numpy as np

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2. Initializing a Qubit

# Create a qubit in the state |0⟩ (alpha=1, beta=0)
q = Qubit(1, 0)
print(f"Initial state: {q}")
# Output: Qubit((1+0j), (0+0j))

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3. Applying Gates

Hadamard Gate – Creating Superposition

q = Qubit(1, 0)      # Start in |0⟩
q.hadamard()
print(f"State after Hadamard: {q}")

probs = q.probabilities()
print(f"Probabilities: P(|0⟩)={probs[0]:.1%}, P(|1⟩)={probs[1]:.1%}")

Pauli-X (NOT) Gate

q = Qubit(1, 0)
print(f"Before Pauli-X: {q}")

q.pauliX()
print(f"After Pauli-X: {q}")

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4. Performing a Measurement

q = Qubit(1, 1)  # Automatically normalized to superposition
print(f"Superposition: {q}")

print("Performing 10 measurements...")
for _ in range(10):
    result = q.measure()
    print(f"Measured: {result}, Collapsed state: {q}")

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5. Applying Rotation Gates

q = Qubit(1, 0)

# Rotate by 90° (π/2 radians) around Y-axis
q.rY(np.pi / 2)
print(f"After rY(Ï€/2): {q}")
print(f"Probabilities: {q.probabilities()}")

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🔭 Future Plans (v0.2+)

• Multi-Qubit Systems: Add QuantumRegister to manage multiple qubits.
• Entanglement Support: Add CNOT, Toffoli, and other multi-qubit gates.
• Quantum Circuits: Circuit builder and execution.
• Performance Boosts: Optimized calculations for larger systems.
• Visualization: Bloch sphere and state vector plotting tools.

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📄 License

This project is licensed under the MIT License.