def compile_controlled_rotation(gate: RotationGateImpl,
angles: list = None) -> QCircuit:
"""
Recompilation of a controlled-rotation gate
Basis change into Rz then recompilation of controled Rz, then change basis back
:param gate: The rotational gate
:param angles: new angles to set, given as a list of two. If None the angle in the gate is used (default)
:return: set of gates wrapped in QCircuit class
"""
if not gate.is_controlled():
return QCircuit.wrap_gate(gate)
if not isinstance(gate, RotationGateImpl):
return QCircuit.wrap_gate(gate)
if angles is None:
angles = [gate.parameter / 2, -gate.parameter / 2]
if len(gate.target) > 1:
return compile_controlled_rotation(gate=compile_multitarget(gate=gate),
angles=angles)
target = gate.target
control = gate.control
result = QCircuit()
result += change_basis(target=target, axis=gate._axis)
result += RotationGateImpl(axis="z", target=target, angle=angles[0])
result += QGateImpl(name="X", target=target, control=control)
result += RotationGateImpl(axis="Z", target=target, angle=angles[1])
result += QGateImpl(name="X", target=target, control=control)
result += change_basis(target=target, axis=gate._axis, daggered=True)
result.n_qubits = result.max_qubit() + 1
return result
def compile_ch(gate: QGateImpl) -> QCircuit:
"""
Compile CH gates into its equivalent:
CH = Ry(0.25pi) CZ Ry(-0.25pi)
Parameters
----------
gate:
the gate.
Returns
-------
QCircuit, the result of compilation.
"""
if gate.name.lower() == "h" and gate.is_controlled():
return Ry(target=gate.target, control=None, angle=-numpy.pi / 4) \
+ Z(target=gate.target, control=gate.control, power=gate.power if gate.is_parametrized() else None) \
+ Ry(target=gate.target, control=None, angle=numpy.pi / 4)
else:
return QCircuit.wrap_gate(gate)
def _initialize_power_gate(name: str,
target: typing.Union[list, int],
control: typing.Union[list, int] = None,
power=None) -> QCircuit:
if power is None or power in [1, 1.0]:
return QCircuit.wrap_gate(
QGateImpl(name=name, target=target, control=control))
else:
return QCircuit.wrap_gate(
PowerGateImpl(name=name,
power=power,
target=target,
control=control))
def QGate(name,
target: typing.Union[list, int],
control: typing.Union[list, int] = None):
return QGateImpl(name=name, target=target, control=control)