def __init__(
self,
connection: ForestConnection,
noise_model: Optional[NoiseModel] = None,
gate_noise: Optional[List[float]] = None,
measurement_noise: Optional[List[float]] = None,
random_seed: Optional[int] = None,
requires_executable: bool = False,
) -> None:
"""
A virtual machine that classically emulates the execution of Quil programs.
:param connection: A connection to the Forest web API.
:param noise_model: A noise model that describes noise to apply when emulating a program's
execution.
:param gate_noise: A list of three numbers [Px, Py, Pz] indicating the probability of an X,
Y, or Z gate getting applied to each qubit after a gate application or reset. The
default value of None indicates no noise.
:param measurement_noise: A list of three numbers [Px, Py, Pz] indicating the probability
of an X, Y, or Z gate getting applied before a measurement. The default value of
None indicates no noise.
:param random_seed: A seed for the QVM's random number generators. Either None (for an
automatically generated seed) or a non-negative integer.
:param requires_executable: Whether this QVM will refuse to run a :py:class:`Program` and
only accept the result of :py:func:`compiler.native_quil_to_executable`. Setting this
to True better emulates the behavior of a QPU.
"""
super().__init__()
if (noise_model is not None) and (gate_noise is not None or measurement_noise is not None):
raise ValueError(
"""
You have attempted to supply the QVM with both a Kraus noise model
(by supplying a `noise_model` argument), as well as either `gate_noise`
or `measurement_noise`. At this time, only one may be supplied.
To read more about supplying noise to the QVM, see
http://pyquil.readthedocs.io/en/latest/noise_models.html#support-for-noisy-gates-on-the-rigetti-qvm.
"""
)
self.noise_model = noise_model
self.connection = connection
validate_noise_probabilities(gate_noise)
validate_noise_probabilities(measurement_noise)
self.gate_noise = gate_noise
self.measurement_noise = measurement_noise
if random_seed is None:
self.random_seed = None
elif isinstance(random_seed, int) and random_seed >= 0:
self.random_seed = random_seed
else:
raise TypeError("random_seed should be None or a non-negative int")
self.requires_executable = requires_executable
self.connect()
def test_validate_noise_probabilities():
with pytest.raises(TypeError):
validate_noise_probabilities(1)
with pytest.raises(TypeError):
validate_noise_probabilities(['a', 'b', 'c'])
with pytest.raises(ValueError):
validate_noise_probabilities([0.0, 0.0, 0.0, 0.0])
with pytest.raises(ValueError):
validate_noise_probabilities([0.5, 0.5, 0.5])
with pytest.raises(ValueError):
validate_noise_probabilities([-0.5, -0.5, -0.5])
def test_validate_noise_probabilities():
with pytest.raises(TypeError):
validate_noise_probabilities(1)
with pytest.raises(TypeError):
validate_noise_probabilities(["a", "b", "c"])
with pytest.raises(ValueError):
validate_noise_probabilities([0.0, 0.0, 0.0, 0.0])
with pytest.raises(ValueError):
validate_noise_probabilities([0.5, 0.5, 0.5])
with pytest.raises(ValueError):
validate_noise_probabilities([-0.5, -0.5, -0.5])
def __init__(self,
connection: ForestConnection,
*args,
noise_model=None,
gate_noise=None,
measurement_noise=None,
random_seed=None,
**kwargs):
"""
A virtual machine that classically emulates the execution of Quil programs.
:param connection: A connection to the Forest web API.
:param noise_model: A noise model that describes noise to apply when emulating a program's
execution.
:param gate_noise: A list of three numbers [Px, Py, Pz] indicating the probability of an X,
Y, or Z gate getting applied to each qubit after a gate application or reset. The
default value of None indicates no noise.
:param measurement_noise: A list of three numbers [Px, Py, Pz] indicating the probability
of an X, Y, or Z gate getting applied before a measurement. The default value of
None indicates no noise.
:param random_seed: A seed for the QVM's random number generators. Either None (for an
automatically generated seed) or a non-negative integer.
"""
super().__init__(*args, **kwargs)
if (noise_model is not None) and (gate_noise is not None
or measurement_noise is not None):
raise ValueError("""
You have attempted to supply the QVM with both a Kraus noise model
(by supplying a `noise_model` argument), as well as either `gate_noise`
or `measurement_noise`. At this time, only one may be supplied.
To read more about supplying noise to the QVM, see http://pyquil.readthedocs.io/en/latest/noise_models.html#support-for-noisy-gates-on-the-rigetti-qvm.
""")
self.noise_model = noise_model
self.connection = connection
validate_noise_probabilities(gate_noise)
validate_noise_probabilities(measurement_noise)
self.gate_noise = gate_noise
self.measurement_noise = measurement_noise
if random_seed is None:
self.random_seed = None
elif isinstance(random_seed, integer_types) and random_seed >= 0:
self.random_seed = random_seed
else:
raise TypeError("random_seed should be None or a non-negative int")
def __init__(self, device=None, endpoint=None,
gate_noise=None, measurement_noise=None, random_seed=None,
compiler_endpoint=None):
"""
Constructor for QVMConnection. Sets up any necessary security, and establishes the noise
model to use.
:param Device device: The optional device, from which noise will be added by default to all
programs run on this instance.
:param endpoint: The endpoint of the server for running small jobs
:param gate_noise: A list of three numbers [Px, Py, Pz] indicating the probability of an X,
Y, or Z gate getting applied to each qubit after a gate application or
reset. (default None)
:param measurement_noise: A list of three numbers [Px, Py, Pz] indicating the probability of
an X, Y, or Z gate getting applied before a a measurement.
(default None)
:param random_seed: A seed for the QVM's random number generators. Either None (for an
automatically generated seed) or a non-negative integer.
"""
if endpoint is None:
pyquil_config = PyquilConfig()
endpoint = pyquil_config.qvm_url
if compiler_endpoint is None:
pyquil_config = PyquilConfig()
compiler_endpoint = pyquil_config.compiler_url
if (device is not None and device.noise_model is not None) and \
(gate_noise is not None or measurement_noise is not None):
raise ValueError("""
You have attempted to supply the QVM with both a device noise model
(by having supplied a device argument), as well as either gate_noise
or measurement_noise. At this time, only one may be supplied.
To read more about supplying noise to the QVM, see http://pyquil.readthedocs.io/en/latest/noise_models.html#support-for-noisy-gates-on-the-rigetti-qvm.
""")
if device is not None and device.noise_model is None:
warnings.warn("""
You have supplied the QVM with a device that does not have a noise model. No noise will be added to
programs run on this QVM.
""")
self.noise_model = device.noise_model if device else None
self.compiler = LocalQVMCompiler(endpoint=compiler_endpoint, device=device) if device \
else None
self.sync_endpoint = endpoint
validate_noise_probabilities(gate_noise)
validate_noise_probabilities(measurement_noise)
self.gate_noise = gate_noise
self.measurement_noise = measurement_noise
if random_seed is None:
self.random_seed = None
elif isinstance(random_seed, integer_types) and random_seed >= 0:
self.random_seed = random_seed
else:
raise TypeError("random_seed should be None or a non-negative int")
self._connection = ForestConnection(sync_endpoint=endpoint)
self.session = self._connection.session # backwards compatibility
