# A Python library for writing, manipulating, and optimizing quantum circuits

## Cirq

Cirq is a Python library for writing, manipulating, and optimizing quantum circuits and running them against quantum computers and simulators.

## Hello Qubit

A simple example to get you up and running:

```
import cirq
# Pick a qubit.
qubit = cirq.GridQubit(0, 0)
# Create a circuit
circuit = cirq.Circuit.from_ops(
cirq.X(qubit)**0.5, # Square root of NOT.
cirq.measure(qubit, key='m') # Measurement.
)
print("Circuit:")
print(circuit)
# Simulate the circuit several times.
simulator = cirq.google.XmonSimulator()
result = simulator.run(circuit, repetitions=20)
print("Results:")
print(result)
```

Example output:

```
Circuit:
(0, 0): ───X^0.5───M('m')───
Results:
m=11000111111011001000
```