def mcu3(self, theta, phi, lam, control_qubits, target_qubit):
"""
Apply Multiple-Controlled U3 gate
Args:
theta: angle theta
phi: angle phi
lam: angle lambda
control_qubits: The list of control qubits
target_qubit: The target qubit
"""
if isinstance(target_qubit, QuantumRegister) and len(target_qubit) == 1:
target_qubit = target_qubit[0]
temp = []
self._check_qargs(control_qubits)
temp += control_qubits
self._check_qargs([target_qubit])
temp.append(target_qubit)
self._check_dups(temp)
n_c = len(control_qubits)
if n_c == 1: # cu3
apply_cu3(self, theta, phi, lam, control_qubits[0], target_qubit)
else:
_apply_mcu3(self, theta, phi, lam, control_qubits, target_qubit)
def mcu3(self, theta, phi, lam, control_qubits, target_qubit):
"""
Apply Multiple-Controlled U3 gate
Args:
self (QuantumCircuit): The QuantumCircuit object to apply the mcu3 gate on.
theta (float): angle theta
phi (float): angle phi
lam (float): angle lambda
control_qubits (list(tuple(QuantumRegister, int))): The list of control qubits
target_qubit (tuple(QuantumRegister, int)): The target qubit
"""
if isinstance(target_qubit, QuantumRegister) and len(target_qubit) == 1:
target_qubit = target_qubit[0]
temp = []
self._check_qargs(control_qubits)
temp += control_qubits
self._check_qargs([target_qubit])
temp.append(target_qubit)
self._check_dups(temp)
n_c = len(control_qubits)
if n_c == 1: # cu3
apply_cu3(self, theta, phi, lam, control_qubits[0], target_qubit)
else:
_apply_mcu3(self, theta, phi, lam, control_qubits, target_qubit)
def mcrx(self, theta, q_controls, q_target, use_basis_gates=False):
"""
Apply Multiple-Controlled X rotation gate
Args:
self (QuantumCircuit): The QuantumCircuit object to apply the mcrx gate on.
theta (float): angle theta
q_controls (list[Qubit]): The list of control qubits
q_target (Qubit): The target qubit
use_basis_gates (bool): use basis gates
Raises:
AquaError: invalid input
"""
# check controls
if isinstance(q_controls, QuantumRegister):
control_qubits = [qb for qb in q_controls]
elif isinstance(q_controls, list):
control_qubits = q_controls
else:
raise AquaError(
'The mcrx gate needs a list of qubits or a quantum register for controls.'
)
# check target
if isinstance(q_target, Qubit):
target_qubit = q_target
else:
raise AquaError('The mcrx gate needs a single qubit as target.')
all_qubits = control_qubits + [target_qubit]
self._check_qargs(all_qubits)
self._check_dups(all_qubits)
n_c = len(control_qubits)
if n_c == 1: # cu3
apply_cu3(self,
theta,
-pi / 2,
pi / 2,
control_qubits[0],
target_qubit,
use_basis_gates=use_basis_gates)
else:
theta_step = theta * (1 / (2**(n_c - 1)))
_apply_mcu3_graycode(self,
theta_step,
-pi / 2,
pi / 2,
control_qubits,
target_qubit,
use_basis_gates=use_basis_gates)
def mcrz(self, lam, q_controls, q_target, use_basis_gates=False):
"""
Apply Multiple-Controlled Z rotation gate
Args:
self (QuantumCircuit): The QuantumCircuit object to apply the mcrz gate on.
phi (float): angle phi
control_qubits (list of Qubit): The list of control qubits
target_qubit (Qubit): The target qubit
"""
# check controls
if isinstance(q_controls, QuantumRegister):
control_qubits = [qb for qb in q_controls]
elif isinstance(q_controls, list):
control_qubits = q_controls
else:
raise AquaError(
'The mcrz gate needs a list of qubits or a quantum register for controls.'
)
# check target
if isinstance(q_target, Qubit):
target_qubit = q_target
else:
raise AquaError('The mcrz gate needs a single qubit as target.')
all_qubits = control_qubits + [target_qubit]
self._check_qargs(all_qubits)
self._check_dups(all_qubits)
n_c = len(control_qubits)
if n_c == 1: # cu3
apply_cu3(self,
0,
0,
lam,
control_qubits[0],
target_qubit,
use_basis_gates=use_basis_gates)
else:
lam_step = lam * (1 / (2**(n_c - 1)))
_apply_mcu3_graycode(self,
0,
0,
lam_step,
control_qubits,
target_qubit,
use_basis_gates=use_basis_gates)
def _apply_mcu3_graycode(circuit, theta, phi, lam, ctls, tgt, use_basis_gates):
"""Apply multi-controlled u3 gate from ctls to tgt using graycode
pattern with single-step angles theta, phi, lam."""
n = len(ctls)
gray_code = list(GrayCode(n).generate_gray())
last_pattern = None
for pattern in gray_code:
if '1' not in pattern:
continue
if last_pattern is None:
last_pattern = pattern
# find left most set bit
lm_pos = list(pattern).index('1')
# find changed bit
comp = [i != j for i, j in zip(pattern, last_pattern)]
if True in comp:
pos = comp.index(True)
else:
pos = None
if pos is not None:
if pos != lm_pos:
circuit.cx(ctls[pos], ctls[lm_pos])
else:
indices = [i for i, x in enumerate(pattern) if x == '1']
for idx in indices[1:]:
circuit.cx(ctls[idx], ctls[lm_pos])
# check parity and undo rotation
if pattern.count('1') % 2 == 0:
# inverse CU3: u3(theta, phi, lamb)^dagger = u3(-theta, -lam, -phi)
apply_cu3(circuit,
-theta,
-lam,
-phi,
ctls[lm_pos],
tgt,
use_basis_gates=use_basis_gates)
else:
apply_cu3(circuit,
theta,
phi,
lam,
ctls[lm_pos],
tgt,
use_basis_gates=use_basis_gates)
last_pattern = pattern
def _apply_mcu3(circuit, theta, phi, lam, ctls, tgt):
"""Apply multi-controlled u3 gate from ctls to tgt with angles theta,
phi, lam."""
n = len(ctls)
gray_code = list(GrayCode(n).generate_gray())
last_pattern = None
theta_angle = theta * (1 / (2**(n - 1)))
phi_angle = phi * (1 / (2**(n - 1)))
lam_angle = lam * (1 / (2**(n - 1)))
for pattern in gray_code:
if not '1' in pattern:
continue
if last_pattern is None:
last_pattern = pattern
#find left most set bit
lm_pos = list(pattern).index('1')
#find changed bit
comp = [i != j for i, j in zip(pattern, last_pattern)]
if True in comp:
pos = comp.index(True)
else:
pos = None
if pos is not None:
if pos != lm_pos:
circuit.cx(ctls[pos], ctls[lm_pos])
else:
indices = [i for i, x in enumerate(pattern) if x == '1']
for idx in indices[1:]:
circuit.cx(ctls[idx], ctls[lm_pos])
#check parity
if pattern.count('1') % 2 == 0:
#inverse
apply_cu3(circuit, -theta_angle, phi_angle, lam_angle,
ctls[lm_pos], tgt)
else:
apply_cu3(circuit, theta_angle, phi_angle, lam_angle, ctls[lm_pos],
tgt)
last_pattern = pattern
def mcry(self,
theta,
q_controls,
q_target,
q_ancillae,
mode='basic',
use_basis_gates=False):
"""
Apply Multiple-Controlled Y rotation gate
Args:
self (QuantumCircuit): The QuantumCircuit object to apply the mcry gate on.
theta (float): angle theta
q_controls (list[Qubit]): The list of control qubits
q_target (Qubit): The target qubit
q_ancillae (Union(QuantumRegister,tuple(QuantumRegister, int))):
The list of ancillary qubits.
mode (str): The implementation mode to use
use_basis_gates (bool): use basis gates
Raises:
AquaError: invalid input
"""
# check controls
if isinstance(q_controls, QuantumRegister):
control_qubits = [qb for qb in q_controls]
elif isinstance(q_controls, list):
control_qubits = q_controls
else:
raise AquaError(
'The mcry gate needs a list of qubits or a quantum register for controls.'
)
# check target
if isinstance(q_target, Qubit):
target_qubit = q_target
else:
raise AquaError('The mcry gate needs a single qubit as target.')
# check ancilla
if q_ancillae is None:
ancillary_qubits = []
elif isinstance(q_ancillae, QuantumRegister):
ancillary_qubits = [qb for qb in q_ancillae]
elif isinstance(q_ancillae, list):
ancillary_qubits = q_ancillae
else:
raise AquaError('The mcry gate needs None or a list '
'of qubits or a quantum register for ancilla.')
all_qubits = control_qubits + [target_qubit] + ancillary_qubits
self._check_qargs(all_qubits)
self._check_dups(all_qubits)
if mode == 'basic':
self.u3(theta / 2, 0, 0, q_target)
self.mct(q_controls, q_target, q_ancillae)
self.u3(-theta / 2, 0, 0, q_target)
self.mct(q_controls, q_target, q_ancillae)
elif mode == 'noancilla':
n_c = len(control_qubits)
if n_c == 1: # cu3
apply_cu3(self,
theta,
0,
0,
control_qubits[0],
target_qubit,
use_basis_gates=use_basis_gates)
else:
theta_step = theta * (1 / (2**(n_c - 1)))
_apply_mcu3_graycode(self,
theta_step,
0,
0,
control_qubits,
target_qubit,
use_basis_gates=use_basis_gates)
else:
raise AquaError(
'Unrecognized mode for building MCRY circuit: {}.'.format(mode))