def _write_operations(self,
op_tree: ops.OP_TREE,
output: Callable[[str], None],
output_line_gap: Callable[[int], None],
top=True) -> None:
for op in ops.flatten_op_tree(op_tree):
qasm_op = extension.try_cast( # type: ignore
ops.QasmConvertibleOperation, op)
if qasm_op is not None:
out = qasm_op.known_qasm_output(self.args)
if out is not None:
output(out)
continue
if isinstance(op, ops.GateOperation):
comment = 'Gate: {!s}'.format(op.gate)
else:
comment = 'Operation: {!s}'.format(op)
comp_op = extension.try_cast( # type: ignore
ops.CompositeOperation, op)
if comp_op is not None:
if top:
output_line_gap(1)
output('// {}\n'.format(comment))
self._write_operations(comp_op.default_decompose(),
output,
output_line_gap,
top=False)
if top:
output_line_gap(1)
continue
mat = protocols.unitary(op, None) if len(op.qubits) <= 2 else None
if mat is not None and len(op.qubits) == 1:
u_op = QasmUGate.from_matrix(mat).on(*op.qubits)
if top:
output_line_gap(1)
output('// {}\n'.format(comment))
output(cast(str, u_op.known_qasm_output(self.args)))
if top:
output_line_gap(1)
continue
if mat is not None and len(op.qubits) == 2:
u_op = QasmTwoQubitGate.from_matrix(mat).on(*op.qubits)
if top:
output_line_gap(1)
output('// {}\n'.format(comment))
self._write_operations((u_op, ),
output,
output_line_gap,
top=False)
if top:
output_line_gap(1)
continue
raise ValueError(
'Cannot output operation as QASM: {!r}'.format(op))
def _convert_one(self, op: ops.Operation) -> ops.OP_TREE:
# Don't change if it's already a SingleQubitCliffordGate
if (isinstance(op, ops.GateOperation) and
isinstance(op.gate, ops.SingleQubitCliffordGate)):
return op
# Single qubit gate with known matrix?
if len(op.qubits) == 1:
mat = protocols.unitary(op, None)
if mat is not None:
cliff_op = self._matrix_to_clifford_op(mat, op.qubits[0])
if cliff_op is not None:
return cliff_op
if self.ignore_failures:
return op
raise ValueError('Single qubit operation is not in the '
'Clifford group: {!r}'.format(op))
# Provides a decomposition?
composite_op = extension.try_cast( # type: ignore
ops.CompositeOperation, op)
if composite_op is not None:
return composite_op.default_decompose()
# Just let it be?
if self.ignore_failures:
return op
raise TypeError("Don't know how to work with {!r}. "
"It isn't a CompositeOperation or a 1-qubit operation "
"with a known unitary effect.".format(op))
def _convert_one(self, op: ops.Operation) -> ops.OP_TREE:
# Check if this is a CZ
# Only keep partial CZ gates if allow_partial_czs
if (isinstance(op, ops.GateOperation)
and isinstance(op.gate, ops.Rot11Gate)
and (self.allow_partial_czs or op.gate.half_turns == 1)):
return op
# Measurement?
if ops.MeasurementGate.is_measurement(op):
return op
# Known matrix?
mat = protocols.unitary(op, None)
if mat is not None and len(op.qubits) == 1:
return op
if mat is not None and len(op.qubits) == 2:
return decompositions.two_qubit_matrix_to_operations(
op.qubits[0], op.qubits[1], mat, allow_partial_czs=False)
# Provides a decomposition?
composite_op = extension.try_cast( # type: ignore
ops.CompositeOperation, op)
if composite_op is not None:
return composite_op.default_decompose()
# Just let it be?
if self.ignore_failures:
return op
raise TypeError("Don't know how to work with {!r}. "
"It isn't a CompositeOperation or an operation with a "
"known unitary effect on 1 or 2 qubits.".format(op))
def decompose_depth(*operations, d=1):
if d <= 0:
yield from operations
return
for op in ops.flatten_op_tree(operations):
composite_op = extension.try_cast(ops.CompositeOperation, op)
if composite_op is not None:
yield from decompose_depth(composite_op.default_decompose(), d=d-1)
else:
yield op
def inverse(val: Any, default: Any = RaiseTypeErrorIfNotProvided) -> Any:
"""Returns the inverse `val**-1` of the given value, if defined.
An object can define an inverse by defining a __pow__(self, exponent) method
that returns something besides NotImplemented when given the exponent -1.
The inverse of iterables is by default defined to be the iterable's items,
each inverted, in reverse order.
Args:
val: The value (or iterable of invertable values) to invert.
default: Determines the fallback behavior when `val` doesn't have
an inverse defined. If `default` is not set, a TypeError is raised.
If `default` is set to a value, that value is returned.
Returns:
If `val` has a __pow__ method that returns something besides
NotImplemented when given an exponent of -1, that result is returned.
Otherwise, if `val` is iterable, the result is a tuple with the same
items as `val` but in reverse order and with each item inverted.
Otherwise, if a `default` argument was specified, it is returned.
Raises:
TypeError: `val` doesn't have a __pow__ method, or that method returned
NotImplemented when given -1. Furthermore `val` isn't an
iterable containing invertible items. Also, no `default` argument
was specified.
"""
# TODO: remove this compatibility shim when ReversibleEffect is gone.
from cirq import extension, ops
reversible = extension.try_cast(ops.ReversibleEffect, val)
if reversible is not None:
return reversible.inverse()
# Check if object defines an inverse via __pow__.
raiser = getattr(val, '__pow__', None)
result = NotImplemented if raiser is None else raiser(-1)
if result is not NotImplemented:
return result
# Maybe it's an iterable of invertable items?
# Note: we avoid str because 'a'[0] == 'a', which creates an infinite loop.
if isinstance(val, collections.Iterable) and not isinstance(val, str):
unique_indicator = []
results = tuple(inverse(e, unique_indicator) for e in val)
if all(e is not unique_indicator for e in results):
return results[::-1]
# Can't invert.
if default is not RaiseTypeErrorIfNotProvided:
return default
raise TypeError(
"object of type '{}' isn't invertable. "
"It has no __pow__ method (or the method returned NotImplemented) "
"and it isn't an iterable of invertable objects.".format(type(val)))
def _decompose(self, op: ops.Operation) -> ops.OP_TREE:
"""Recursively decompose composite gates into an OP_TREE of gates."""
skip = self.no_decomp(op)
if skip and (skip is not NotImplemented):
return op
composite_op = extension.try_cast( # type: ignore
ops.CompositeOperation, op)
if composite_op is None:
return op
op_iter = ops.flatten_op_tree(composite_op.default_decompose())
return (self._decompose(op) for op in op_iter)
def _group_interchangeable_qubits(
self
) -> Tuple[Union[raw_types.QubitId, Tuple[
int, FrozenSet[raw_types.QubitId]]], ...]:
cast_gate = extension.try_cast(gate_features.InterchangeableQubitsGate,
self.gate)
if cast_gate is None:
return self.qubits
groups = {} # type: Dict[int, List[raw_types.QubitId]]
for i, q in enumerate(self.qubits):
k = cast_gate.qubit_index_to_equivalence_group_key(i)
if k not in groups:
groups[k] = []
groups[k].append(q)
return tuple(sorted((k, frozenset(v)) for k, v in groups.items()))
def _group_interchangeable_qubits(self) -> Tuple[
Union[raw_types.QubitId,
Tuple[int, FrozenSet[raw_types.QubitId]]],
...]:
cast_gate = extension.try_cast(gate_features.InterchangeableQubitsGate,
self.gate)
if cast_gate is None:
return self.qubits
groups = {} # type: Dict[int, List[raw_types.QubitId]]
for i, q in enumerate(self.qubits):
k = cast_gate.qubit_index_to_equivalence_group_key(i)
if k not in groups:
groups[k] = []
groups[k].append(q)
return tuple(sorted((k, frozenset(v)) for k, v in groups.items()))
def unitary(
val: Any,
default: TDefault = RaiseTypeErrorIfNotProvided
) -> Union[np.ndarray, TDefault]:
"""Returns a unitary matrix describing the given value.
Args:
val: The value to describe with a unitary matrix.
default: Determines the fallback behavior when `val` doesn't have
a unitary matrix. If `default` is not set, a TypeError is raised. If
default is set to a value, that value is returned.
Returns:
If `val` has a _unitary_ method and its result is not NotImplemented,
that result is returned. Otherwise, if a default value was specified,
the default value is returned.
Raises:
TypeError: `val` doesn't have a _unitary_ method (or that method
returned NotImplemented) and also no default value was specified.
"""
getter = getattr(val, '_unitary_', None)
result = NotImplemented if getter is None else getter()
# Temporary compatibility shim for classes using KnownMatrix.
if result is NotImplemented:
known = extension.try_cast(KnownMatrix, val)
result = NotImplemented if known is None else known.matrix()
if result is not NotImplemented:
return result
if default is not RaiseTypeErrorIfNotProvided:
return default
if getter is None:
raise TypeError("object of type '{}' "
"has no _unitary_ method.".format(type(val)))
raise TypeError("object of type '{}' does have a _unitary_ method, "
"but it returned NotImplemented.".format(type(val)))