def test_qregs(self):
"""Test getting quantum registers from circuit."""
qr1 = QuantumRegister(10, "q")
self.assertEqual(qr1.name, "q")
self.assertEqual(qr1.size, 10)
self.assertEqual(type(qr1), QuantumRegister)
def test_append_opaque_wrong_dimension(self):
"""test appending opaque gate to wrong dimension wires."""
qr = QuantumRegister(2)
circ = QuantumCircuit(qr)
opaque_gate = Gate(name="crz_2", num_qubits=2, params=[0.5])
self.assertRaises(CircuitError, circ.append, opaque_gate, [qr[0]])
def run(self, dag):
"""Run the ConsolidateBlocks pass on `dag`.
Iterate over each block and replace it with an equivalent Unitary
on the same wires.
"""
if self.decomposer is None:
return dag
new_dag = DAGCircuit()
for qreg in dag.qregs.values():
new_dag.add_qreg(qreg)
for creg in dag.cregs.values():
new_dag.add_creg(creg)
# compute ordered indices for the global circuit wires
global_index_map = {wire: idx for idx, wire in enumerate(dag.qubits)}
blocks = self.property_set['block_list']
# just to make checking if a node is in any block easier
all_block_nodes = {nd for bl in blocks for nd in bl}
for node in dag.topological_op_nodes():
if node not in all_block_nodes:
# need to add this node to find out where in the list it goes
preds = [
nd for nd in dag.predecessors(node) if nd.type == 'op'
]
block_count = 0
while preds:
if block_count < len(blocks):
block = blocks[block_count]
# if any of the predecessors are in the block, remove them
preds = [p for p in preds if p not in block]
else:
# should never occur as this would mean not all
# nodes before this one topologically had been added
# so not all predecessors were removed
raise TranspilerError(
"Not all predecessors removed due to error"
" in topological order")
block_count += 1
# we have now seen all predecessors
# so update the blocks list to include this block
blocks = blocks[:block_count] + [[node]] + blocks[block_count:]
# create the dag from the updated list of blocks
basis_gate_name = self.decomposer.gate.name
for block in blocks:
if len(block) == 1 and (block[0].name != basis_gate_name
or block[0].op.is_parameterized()):
# an intermediate node that was added into the overall list
new_dag.apply_operation_back(block[0].op, block[0].qargs,
block[0].cargs)
else:
# find the qubits involved in this block
block_qargs = set()
block_cargs = set()
for nd in block:
block_qargs |= set(nd.qargs)
if nd.condition:
block_cargs |= set(nd.condition[0])
# convert block to a sub-circuit, then simulate unitary and add
q = QuantumRegister(len(block_qargs))
# if condition in node, add clbits to circuit
if len(block_cargs) > 0:
c = ClassicalRegister(len(block_cargs))
subcirc = QuantumCircuit(q, c)
else:
subcirc = QuantumCircuit(q)
block_index_map = self._block_qargs_to_indices(
block_qargs, global_index_map)
basis_count = 0
for nd in block:
if nd.op.name == basis_gate_name:
basis_count += 1
subcirc.append(nd.op,
[q[block_index_map[i]] for i in nd.qargs])
unitary = UnitaryGate(
Operator(subcirc)) # simulates the circuit
max_2q_depth = 20 # If depth > 20, there will be 1q gates to consolidate.
if (self.force_consolidate or unitary.num_qubits > 2 or
self.decomposer.num_basis_gates(unitary) < basis_count
or len(subcirc) > max_2q_depth):
new_dag.apply_operation_back(
UnitaryGate(unitary),
sorted(block_qargs, key=lambda x: block_index_map[x]))
else:
for nd in block:
new_dag.apply_operation_back(nd.op, nd.qargs, nd.cargs)
return new_dag
CCXGate,
YGate,
CYGate,
RYYGate,
ECRGate,
ZGate,
CZGate,
)
_sel = StandardEquivalenceLibrary = EquivalenceLibrary()
# Import existing gate definitions
# HGate
q = QuantumRegister(1, 'q')
def_h = QuantumCircuit(q)
def_h.append(U2Gate(0, pi), [q[0]], [])
_sel.add_equivalence(HGate(), def_h)
# CHGate
q = QuantumRegister(2, 'q')
def_ch = QuantumCircuit(q)
for inst, qargs, cargs in [(SGate(), [q[1]], []), (HGate(), [q[1]], []),
(TGate(), [q[1]], []), (CXGate(), [q[0], q[1]], []),
(TdgGate(), [q[1]], []), (HGate(), [q[1]], []),
(SdgGate(), [q[1]], [])]:
def_ch.append(inst, qargs, cargs)
_sel.add_equivalence(CHGate(), def_ch)
def test_dag_get_qubits(self):
"""get_qubits() method """
dag = DAGCircuit()
dag.add_qreg(QuantumRegister(1, 'qr1'))
dag.add_qreg(QuantumRegister(1, 'qr10'))
dag.add_qreg(QuantumRegister(1, 'qr0'))
dag.add_qreg(QuantumRegister(1, 'qr3'))
dag.add_qreg(QuantumRegister(1, 'qr4'))
dag.add_qreg(QuantumRegister(1, 'qr6'))
self.assertListEqual(dag.qubits(), [(QuantumRegister(1, 'qr1'), 0),
(QuantumRegister(1, 'qr10'), 0),
(QuantumRegister(1, 'qr0'), 0),
(QuantumRegister(1, 'qr3'), 0),
(QuantumRegister(1, 'qr4'), 0),
(QuantumRegister(1, 'qr6'), 0)])
import os
from qiskit import execute
from qiskit.circuit import QuantumRegister, ClassicalRegister, QuantumCircuit
from quantuminspire.credentials import get_authentication
from quantuminspire.qiskit import QI
QI_URL = os.getenv('API_URL', 'https://api.quantum-inspire.com/')
project_name = 'Qiskit-entangle'
authentication = get_authentication()
QI.set_authentication(authentication, QI_URL, project_name=project_name)
qi_backend = QI.get_backend('QX single-node simulator')
q = QuantumRegister(2)
b = ClassicalRegister(2)
circuit = QuantumCircuit(q, b)
circuit.h(q[0])
circuit.cx(q[0], q[1])
circuit.measure(q, b)
qi_job = execute(circuit, backend=qi_backend, shots=256)
qi_result = qi_job.result()
histogram = qi_result.get_counts(circuit)
print('\nState\tCounts')
[
print('{0}\t\t{1}'.format(state, counts))
for state, counts in histogram.items()
]
def __init__(self,
num_result_qubits: Optional[int] = None,
quadratic: Optional[Union[np.ndarray, List[List[Union[
float, ParameterExpression]]]]] = None,
linear: Optional[Union[np.ndarray, List[Union[
float, ParameterExpression]]]] = None,
offset: Optional[Union[float, ParameterExpression]] = None,
little_endian: bool = True) -> None:
r"""
Args:
num_result_qubits: The number of qubits to encode the result. Called :math:`m` in
the class documentation.
quadratic: A matrix containing the quadratic coefficients, :math:`A`.
linear: An array containing the linear coefficients, :math:`b`.
offset: A constant offset, :math:`c`.
little_endian: Encode the result in little endianness.
Raises:
ValueError: If ``linear`` and ``quadratic`` have mismatching sizes.
ValueError: If ``num_result_qubits`` is unspecified but cannot be determined because
some values of the quadratic form are parameterized.
"""
# check inputs match
if quadratic is not None and linear is not None:
if len(quadratic) != len(linear):
raise ValueError('Mismatching sizes of quadratic and linear.')
# temporarily set quadratic and linear to [] instead of None so we can iterate over them
if quadratic is None:
quadratic = []
if linear is None:
linear = []
if offset is None:
offset = 0
num_input_qubits = np.max([1, len(linear), len(quadratic)])
# deduce number of result bits if not added
if num_result_qubits is None:
# check no value is parameterized
if (any(
any(isinstance(q_ij, ParameterExpression) for q_ij in q_i)
for q_i in quadratic) or any(
isinstance(l_i, ParameterExpression) for l_i in linear)
or isinstance(offset, ParameterExpression)):
raise ValueError(
'If the number of result qubits is not specified, the quadratic '
'form matrices/vectors/offset may not be parameterized.')
num_result_qubits = self.required_result_qubits(
quadratic, linear, offset)
qr_input = QuantumRegister(num_input_qubits)
qr_result = QuantumRegister(num_result_qubits)
super().__init__(qr_input, qr_result, name='Q(x)')
# set quadratic and linear again to None if they were None
if len(quadratic) == 0:
quadratic = None
if len(linear) == 0:
linear = None
scaling = np.pi * 2**(1 - num_result_qubits)
# initial QFT (just hadamards)
self.h(qr_result)
if little_endian:
qr_result = qr_result[::-1]
# constant coefficient
if offset != 0:
for i, q_i in enumerate(qr_result):
self.u1(scaling * 2**i * offset, q_i)
# the linear part consists of the vector and the diagonal of the
# matrix, since x_i * x_i = x_i, as x_i is a binary variable
for j in range(num_input_qubits):
value = linear[j] if linear is not None else 0
value += quadratic[j][j] if quadratic is not None else 0
if value != 0:
for i, q_i in enumerate(qr_result):
self.cu1(scaling * 2**i * value, qr_input[j], q_i)
# the quadratic part adds A_ij and A_ji as x_i x_j == x_j x_i
if quadratic is not None:
for j in range(num_input_qubits):
for k in range(j + 1, num_input_qubits):
value = quadratic[j][k] + quadratic[k][j]
if value != 0:
for i, q_i in enumerate(qr_result):
self.mcu1(scaling * 2**i * value,
[qr_input[j], qr_input[k]], q_i)
# add the inverse QFT
iqft = QFT(num_result_qubits, do_swaps=False).inverse()
self.append(iqft, qr_result)
def _define(self):
"""The standard definition used the Gray code implementation."""
q = QuantumRegister(self.num_qubits, name='q')
self.definition = [(MCXGrayCode(self.num_ctrl_qubits), q[:], [])]
def _define(self):
"""Define the MCX gate using a V-chain of CX gates."""
q = QuantumRegister(self.num_qubits, name='q')
q_controls = q[:self.num_ctrl_qubits]
q_target = q[self.num_ctrl_qubits]
q_ancillas = q[self.num_ctrl_qubits + 1:]
definition = []
if self._dirty_ancillas:
i = self.num_ctrl_qubits - 3
ancilla_pre_rule = [
(U2Gate(0, numpy.pi), [q_target], []),
(CXGate(), [q_target, q_ancillas[i]], []),
(U1Gate(-numpy.pi / 4), [q_ancillas[i]], []),
(CXGate(), [q_controls[-1], q_ancillas[i]], []),
(U1Gate(numpy.pi / 4), [q_ancillas[i]], []),
(CXGate(), [q_target, q_ancillas[i]], []),
(U1Gate(-numpy.pi / 4), [q_ancillas[i]], []),
(CXGate(), [q_controls[-1], q_ancillas[i]], []),
(U1Gate(numpy.pi / 4), [q_ancillas[i]], []),
]
for inst in ancilla_pre_rule:
definition.append(inst)
for j in reversed(range(2, self.num_ctrl_qubits - 1)):
definition.append(
(RCCXGate(),
[q_controls[j], q_ancillas[i - 1], q_ancillas[i]], []))
i -= 1
definition.append(
(RCCXGate(), [q_controls[0], q_controls[1], q_ancillas[0]], []))
i = 0
for j in range(2, self.num_ctrl_qubits - 1):
definition.append(
(RCCXGate(), [q_controls[j], q_ancillas[i],
q_ancillas[i + 1]], []))
i += 1
if self._dirty_ancillas:
ancilla_post_rule = [
(U1Gate(-numpy.pi / 4), [q_ancillas[i]], []),
(CXGate(), [q_controls[-1], q_ancillas[i]], []),
(U1Gate(numpy.pi / 4), [q_ancillas[i]], []),
(CXGate(), [q_target, q_ancillas[i]], []),
(U1Gate(-numpy.pi / 4), [q_ancillas[i]], []),
(CXGate(), [q_controls[-1], q_ancillas[i]], []),
(U1Gate(numpy.pi / 4), [q_ancillas[i]], []),
(CXGate(), [q_target, q_ancillas[i]], []),
(U2Gate(0, numpy.pi), [q_target], []),
]
for inst in ancilla_post_rule:
definition.append(inst)
else:
definition.append(
(CCXGate(), [q_controls[-1], q_ancillas[i], q_target], []))
for j in reversed(range(2, self.num_ctrl_qubits - 1)):
definition.append(
(RCCXGate(), [q_controls[j], q_ancillas[i - 1],
q_ancillas[i]], []))
i -= 1
definition.append(
(RCCXGate(), [q_controls[0], q_controls[1], q_ancillas[i]], []))
if self._dirty_ancillas:
for i, j in enumerate(list(range(2, self.num_ctrl_qubits - 1))):
definition.append(
(RCCXGate(),
[q_controls[j], q_ancillas[i], q_ancillas[i + 1]], []))
self.definition = definition
def test_qarg_noninteger_float(self):
"""Test attempt to pass non-integer float to QuantumRegister."""
self.assertRaises(CircuitError, QuantumRegister, 2.2)
# but an integer float should pass
qr = QuantumRegister(2.0)
self.assertEqual(qr.size, 2)
def _multiplex(self, target_gate, list_of_angles):
"""
Return a recursive implementation of a multiplexor circuit,
where each instruction itself has a decomposition based on
smaller multiplexors.
The LSB is the multiplexor "data" and the other bits are multiplexor "select".
Args:
target_gate (Gate): Ry or Rz gate to apply to target qubit, multiplexed
over all other "select" qubits
list_of_angles (list[float]): list of rotation angles to apply Ry and Rz
Returns:
DAGCircuit: the circuit implementing the multiplexor's action
"""
list_len = len(list_of_angles)
local_num_qubits = int(math.log2(list_len)) + 1
q = QuantumRegister(local_num_qubits)
circuit = QuantumCircuit(q,
name="multiplex" + local_num_qubits.__str__())
lsb = q[0]
msb = q[local_num_qubits - 1]
# case of no multiplexing: base case for recursion
if local_num_qubits == 1:
circuit.append(target_gate(list_of_angles[0]), [q[0]])
return circuit
# calc angle weights, assuming recursion (that is the lower-level
# requested angles have been correctly implemented by recursion
angle_weight = scipy.kron([[0.5, 0.5], [0.5, -0.5]],
np.identity(2**(local_num_qubits - 2)))
# calc the combo angles
list_of_angles = angle_weight.dot(np.array(list_of_angles)).tolist()
# recursive step on half the angles fulfilling the above assumption
multiplex_1 = self._multiplex(target_gate,
list_of_angles[0:(list_len // 2)])
circuit.append(multiplex_1.to_instruction(), q[0:-1])
# attach CNOT as follows, thereby flipping the LSB qubit
circuit.append(CnotGate(), [msb, lsb])
# implement extra efficiency from the paper of cancelling adjacent
# CNOTs (by leaving out last CNOT and reversing (NOT inverting) the
# second lower-level multiplex)
multiplex_2 = self._multiplex(target_gate,
list_of_angles[(list_len // 2):])
if list_len > 1:
circuit.append(multiplex_2.to_instruction().mirror(), q[0:-1])
else:
circuit.append(multiplex_2.to_instruction(), q[0:-1])
# attach a final CNOT
circuit.append(CnotGate(), [msb, lsb])
return circuit
def test_qregs_eq_invalid_type(self):
"""Test getting quantum registers from circuit."""
qr1 = QuantumRegister(10, "q")
self.assertNotEqual(qr1, 3.14)
def test_apply_cx_to_non_register(self):
"""test applying ccx to non-register raises"""
qr = QuantumRegister(10)
cr = ClassicalRegister(10)
qc = QuantumCircuit(qr, cr)
self.assertRaises(CircuitError, qc.cx, qc[0:2], qc[2:4])
def test_apply_ccx_to_empty_slice(self):
"""test applying ccx to non-register raises"""
qr = QuantumRegister(10)
cr = ClassicalRegister(10)
qc = QuantumCircuit(qr, cr)
self.assertRaises(CircuitError, qc.ccx, qr[2:0], qr[4:2], qr[7:5])
def convert(
self,
operator: CircuitStateFn,
params: Union[ParameterExpression, ParameterVector,
List[ParameterExpression]],
) -> ListOp:
r"""
Args:
operator: The operator corresponding to the quantum state :math:`|\psi(\omega)\rangle`
for which we compute the QFI.
params: The parameters :math:`\omega` with respect to which we are computing the QFI.
Returns:
A ``ListOp[ListOp]`` where the operator at position ``[k][l]`` corresponds to the matrix
element :math:`k, l` of the QFI.
Raises:
TypeError: If ``operator`` is an unsupported type.
"""
# QFI & phase fix observable
qfi_observable = ~StateFn(4 * Z ^ (I ^ operator.num_qubits))
phase_fix_observable = StateFn(
(Z + 1j * Y) ^ (I ^ operator.num_qubits), is_measurement=True)
# see https://arxiv.org/pdf/quant-ph/0108146.pdf
# Check if the given operator corresponds to a quantum state given as a circuit.
if not isinstance(operator, CircuitStateFn):
raise TypeError(
"LinCombFull is only compatible with states that are given as "
f"CircuitStateFn, not {type(operator)}")
# If a single parameter is given wrap it into a list.
if isinstance(params, ParameterExpression):
params = [params]
elif isinstance(params, ParameterVector):
params = params[:] # unroll to list
# First, the operators are computed which can compensate for a potential phase-mismatch
# between target and trained state, i.e.〈ψ|∂lψ〉
gradient_states = LinComb()._gradient_states(
operator,
meas_op=phase_fix_observable,
target_params=params,
open_ctrl=False,
trim_after_grad_gate=True,
)
# if type(gradient_states) in [ListOp, SummedOp]: # pylint: disable=unidiomatic-typecheck
if type(gradient_states) == ListOp:
phase_fix_states = gradient_states.oplist
else:
phase_fix_states = [gradient_states]
# Get 4 * Re[〈∂kψ|∂lψ]
qfi_operators = []
# Add a working qubit
qr_work = QuantumRegister(1, "work_qubit")
state_qc = QuantumCircuit(*operator.primitive.qregs, qr_work)
state_qc.h(qr_work)
state_qc.compose(operator.primitive, inplace=True)
# Get the circuits needed to compute〈∂iψ|∂jψ〉
for i, param_i in enumerate(params): # loop over parameters
qfi_ops = []
for j, param_j in enumerate(params[i:], i):
# Get the gates of the quantum state which are parameterized by param_i
qfi_op = []
param_gates_i = state_qc._parameter_table[param_i]
for gate_i, idx_i in param_gates_i:
grad_coeffs_i, grad_gates_i = LinComb._gate_gradient_dict(
gate_i)[idx_i]
# get the location of gate_i, used for trimming
location_i = None
for idx, (op, _, _) in enumerate(state_qc._data):
if op is gate_i:
location_i = idx
break
for grad_coeff_i, grad_gate_i in zip(
grad_coeffs_i, grad_gates_i):
# Get the gates of the quantum state which are parameterized by param_j
param_gates_j = state_qc._parameter_table[param_j]
for gate_j, idx_j in param_gates_j:
grad_coeffs_j, grad_gates_j = LinComb._gate_gradient_dict(
gate_j)[idx_j]
# get the location of gate_j, used for trimming
location_j = None
for idx, (op, _, _) in enumerate(state_qc._data):
if op is gate_j:
location_j = idx
break
for grad_coeff_j, grad_gate_j in zip(
grad_coeffs_j, grad_gates_j):
grad_coeff_ij = np.conj(
grad_coeff_i) * grad_coeff_j
qfi_circuit = LinComb.apply_grad_gate(
state_qc,
gate_i,
idx_i,
grad_gate_i,
grad_coeff_ij,
qr_work,
open_ctrl=True,
trim_after_grad_gate=(location_j <
location_i),
)
# create a copy of the original circuit with the same registers
qfi_circuit = LinComb.apply_grad_gate(
qfi_circuit,
gate_j,
idx_j,
grad_gate_j,
1,
qr_work,
open_ctrl=False,
trim_after_grad_gate=(location_j >=
location_i),
)
qfi_circuit.h(qr_work)
# Convert the quantum circuit into a CircuitStateFn and add the
# coefficients i, j and the original operator coefficient
coeff = operator.coeff
coeff *= np.sqrt(
np.abs(grad_coeff_i) *
np.abs(grad_coeff_j))
state = CircuitStateFn(qfi_circuit,
coeff=coeff)
param_grad = 1
for gate, idx, param in zip(
[gate_i, gate_j], [idx_i, idx_j],
[param_i, param_j]):
param_expression = gate.params[idx]
param_grad *= param_expression.gradient(
param)
meas = param_grad * qfi_observable
term = meas @ state
qfi_op.append(term)
# Compute −4 * Re(〈∂kψ|ψ〉〈ψ|∂lψ〉)
def phase_fix_combo_fn(x):
return 4 * (-0.5) * (x[0] * np.conjugate(x[1]) +
x[1] * np.conjugate(x[0]))
phase_fix = ListOp([phase_fix_states[i], phase_fix_states[j]],
combo_fn=phase_fix_combo_fn)
# Add the phase fix quantities to the entries of the QFI
# Get 4 * Re[〈∂kψ|∂lψ〉−〈∂kψ|ψ〉〈ψ|∂lψ〉]
qfi_ops += [SummedOp(qfi_op) + phase_fix]
qfi_operators.append(ListOp(qfi_ops))
# Return the full QFI
return ListOp(qfi_operators, combo_fn=triu_to_dense)
def setUp(self):
logger = getLogger()
logger.setLevel('DEBUG')
self.output = io.StringIO()
logger.addHandler(StreamHandlerRaiseException(self.output))
self.circuit = QuantumCircuit(QuantumRegister(1))
def _define(self):
"""Calculate a subcircuit that implements this unitary."""
q = QuantumRegister(self.num_qubits, 'q')
qc = QuantumCircuit(q, name=self.name)
qc.append(UnitaryGate(self.to_matrix()), qargs=q[:])
self.definition = qc
def run(self, dag):
"""Return a new circuit that has been optimized."""
runs = dag.collect_runs(["u1", "u2", "u3"])
runs = _split_runs_on_parameters(runs)
for run in runs:
right_name = "u1"
right_parameters = (0, 0, 0) # (theta, phi, lambda)
for current_node in run:
left_name = current_node.name
if (current_node.condition is not None
or len(current_node.qargs) != 1
or left_name not in ["u1", "u2", "u3", "id"]):
raise TranspilerError("internal error")
if left_name == "u1":
left_parameters = (0, 0, current_node.op.params[0])
elif left_name == "u2":
left_parameters = (np.pi / 2, current_node.op.params[0],
current_node.op.params[1])
elif left_name == "u3":
left_parameters = tuple(current_node.op.params)
else:
left_name = "u1" # replace id with u1
left_parameters = (0, 0, 0)
# If there are any sympy objects coming from the gate convert
# to numpy.
left_parameters = tuple([float(x) for x in left_parameters])
# Compose gates
name_tuple = (left_name, right_name)
if name_tuple == ("u1", "u1"):
# u1(lambda1) * u1(lambda2) = u1(lambda1 + lambda2)
right_parameters = (0, 0, right_parameters[2] +
left_parameters[2])
elif name_tuple == ("u1", "u2"):
# u1(lambda1) * u2(phi2, lambda2) = u2(phi2 + lambda1, lambda2)
right_parameters = (np.pi / 2, right_parameters[1] +
left_parameters[2],
right_parameters[2])
elif name_tuple == ("u2", "u1"):
# u2(phi1, lambda1) * u1(lambda2) = u2(phi1, lambda1 + lambda2)
right_name = "u2"
right_parameters = (np.pi / 2, left_parameters[1],
right_parameters[2] +
left_parameters[2])
elif name_tuple == ("u1", "u3"):
# u1(lambda1) * u3(theta2, phi2, lambda2) =
# u3(theta2, phi2 + lambda1, lambda2)
right_parameters = (right_parameters[0],
right_parameters[1] +
left_parameters[2],
right_parameters[2])
elif name_tuple == ("u3", "u1"):
# u3(theta1, phi1, lambda1) * u1(lambda2) =
# u3(theta1, phi1, lambda1 + lambda2)
right_name = "u3"
right_parameters = (left_parameters[0], left_parameters[1],
right_parameters[2] +
left_parameters[2])
elif name_tuple == ("u2", "u2"):
# Using Ry(pi/2).Rz(2*lambda).Ry(pi/2) =
# Rz(pi/2).Ry(pi-2*lambda).Rz(pi/2),
# u2(phi1, lambda1) * u2(phi2, lambda2) =
# u3(pi - lambda1 - phi2, phi1 + pi/2, lambda2 + pi/2)
right_name = "u3"
right_parameters = (np.pi - left_parameters[2] -
right_parameters[1],
left_parameters[1] + np.pi / 2,
right_parameters[2] + np.pi / 2)
elif name_tuple[1] == "nop":
right_name = left_name
right_parameters = left_parameters
else:
# For composing u3's or u2's with u3's, use
# u2(phi, lambda) = u3(pi/2, phi, lambda)
# together with the qiskit.mapper.compose_u3 method.
right_name = "u3"
# Evaluate the symbolic expressions for efficiency
right_parameters = Optimize1qGates.compose_u3(
left_parameters[0], left_parameters[1],
left_parameters[2], right_parameters[0],
right_parameters[1], right_parameters[2])
# Why evalf()? This program:
# OPENQASM 2.0;
# include "qelib1.inc";
# qreg q[2];
# creg c[2];
# u3(0.518016983430947*pi,1.37051598592907*pi,1.36816383603222*pi) q[0];
# u3(1.69867232277986*pi,0.371448347747471*pi,0.461117217930936*pi) q[0];
# u3(0.294319836336836*pi,0.450325871124225*pi,1.46804720442555*pi) q[0];
# measure q -> c;
# took >630 seconds (did not complete) to optimize without
# calling evalf() at all, 19 seconds to optimize calling
# evalf() AFTER compose_u3, and 1 second to optimize
# calling evalf() BEFORE compose_u3.
# 1. Here down, when we simplify, we add f(theta) to lambda to
# correct the global phase when f(theta) is 2*pi. This isn't
# necessary but the other steps preserve the global phase, so
# we continue in that manner.
# 2. The final step will remove Z rotations by 2*pi.
# 3. Note that is_zero is true only if the expression is exactly
# zero. If the input expressions have already been evaluated
# then these final simplifications will not occur.
# TODO After we refactor, we should have separate passes for
# exact and approximate rewriting.
# Y rotation is 0 mod 2*pi, so the gate is a u1
if np.mod(right_parameters[0], (2 * np.pi)) == 0 \
and right_name != "u1":
right_name = "u1"
right_parameters = (0, 0, right_parameters[1] +
right_parameters[2] +
right_parameters[0])
# Y rotation is pi/2 or -pi/2 mod 2*pi, so the gate is a u2
if right_name == "u3":
# theta = pi/2 + 2*k*pi
if np.mod((right_parameters[0] - np.pi / 2),
(2 * np.pi)) == 0:
right_name = "u2"
right_parameters = (np.pi / 2, right_parameters[1],
right_parameters[2] +
(right_parameters[0] - np.pi / 2))
# theta = -pi/2 + 2*k*pi
if np.mod((right_parameters[0] + np.pi / 2),
(2 * np.pi)) == 0:
right_name = "u2"
right_parameters = (np.pi / 2,
right_parameters[1] + np.pi,
right_parameters[2] - np.pi +
(right_parameters[0] + np.pi / 2))
# u1 and lambda is 0 mod 2*pi so gate is nop (up to a global phase)
if right_name == "u1" and np.mod(right_parameters[2],
(2 * np.pi)) == 0:
right_name = "nop"
# Replace the the first node in the run with a dummy DAG which contains a dummy
# qubit. The name is irrelevant, because substitute_node_with_dag will take care of
# putting it in the right place.
run_qarg = QuantumRegister(1, 'q')[0]
new_op = Gate(name="", num_qubits=1, params=[])
if right_name == "u1":
new_op = U1Gate(right_parameters[2])
if right_name == "u2":
new_op = U2Gate(right_parameters[1], right_parameters[2])
if right_name == "u3":
new_op = U3Gate(*right_parameters)
if right_name != 'nop':
new_dag = DAGCircuit()
new_dag.add_qreg(run_qarg.register)
new_dag.apply_operation_back(new_op, [run_qarg], [])
dag.substitute_node_with_dag(run[0], new_dag)
# Delete the other nodes in the run
for current_node in run[1:]:
dag.remove_op_node(current_node)
if right_name == "nop":
dag.remove_op_node(run[0])
return dag
def qs_decomposition(mat, opt_a1=True, decomposer_1q=None, decomposer_2q=None):
"""
Decomposes unitary matrix into one and two qubit gates using Quantum Shannon Decomposition.
┌───┐ ┌───┐ ┌───┐ ┌───┐
─┤ ├─ ───────┤ Rz├─────┤ Ry├─────┤ Rz├─────
│ │ ≃ ┌───┐└─┬─┘┌───┐└─┬─┘┌───┐└─┬─┘┌───┐
/─┤ ├─ /─┤ ├──□──┤ ├──□──┤ ├──□──┤ ├
└───┘ └───┘ └───┘ └───┘ └───┘
The number of CX gates generated with the decomposition without optimizations is,
.. math::
\frac{9}{16} 4^n - frac{3}{2} 2^n
If opt_a1=True, the CX count is further reduced by,
.. math::
\frac{1}{3} 4^{n - 2} - 1
This decomposition is described in arXiv:quant-ph/0406176.
Arguments:
mat (ndarray): unitary matrix to decompose
opt_a1 (bool): whether to try optimization A.1 from Shende. This should eliminate 1 cnot
per call. If True CZ gates are left in the output. If desired these can be further decomposed
to CX.
decomposer_1q (None or Object): optional 1Q decomposer. If None, uses
:class:`~qiskit.quantum_info.synthesis.one_qubit_decomposer.OneQubitEulerDecomser`
decomposer_2q (None or Object): optional 2Q decomposer. If None, uses
:class:`~qiskit.quantum_info.synthesis.two_qubit_decomposer.TwoQubitBasisDecomposer`
with CXGate.
Return:
QuantumCircuit: Decomposed quantum circuit.
"""
dim = mat.shape[0]
nqubits = int(np.log2(dim))
if np.allclose(np.identity(dim), mat):
return QuantumCircuit(nqubits)
if dim == 2:
if decomposer_1q is None:
decomposer_1q = one_qubit_decompose.OneQubitEulerDecomposer()
circ = decomposer_1q(mat)
elif dim == 4:
if decomposer_2q is None:
decomposer_2q = two_qubit_decompose.TwoQubitBasisDecomposer(CXGate())
circ = decomposer_2q(mat)
else:
qr = QuantumRegister(nqubits)
circ = QuantumCircuit(qr)
dim_o2 = dim // 2
# perform cosine-sine decomposition
(u1, u2), vtheta, (v1h, v2h) = scipy.linalg.cossin(mat, separate=True, p=dim_o2, q=dim_o2)
# left circ
left_circ = _demultiplex(v1h, v2h, opt_a1=opt_a1)
circ.append(left_circ.to_instruction(), qr)
# middle circ
if opt_a1:
nangles = len(vtheta)
half_size = nangles // 2
# get UCG in terms of CZ
circ_cz = _get_ucry_cz(nqubits, (2 * vtheta).tolist())
circ.append(circ_cz.to_instruction(), range(nqubits))
# merge final cz with right-side generic multiplexer
u2[:, half_size:] = np.negative(u2[:, half_size:])
else:
circ.ucry((2 * vtheta).tolist(), qr[:-1], qr[-1])
# right circ
right_circ = _demultiplex(u1, u2, opt_a1=opt_a1)
circ.append(right_circ.to_instruction(), qr)
return circ
def run(self, dag):
"""iterate over each block and replace it with an equivalent Unitary
on the same wires.
"""
new_dag = DAGCircuit()
for qreg in dag.qregs.values():
new_dag.add_qreg(qreg)
for creg in dag.cregs.values():
new_dag.add_creg(creg)
# compute ordered indices for the global circuit wires
global_index_map = {}
for wire in dag.wires:
if not isinstance(wire[0], QuantumRegister):
continue
global_qregs = list(dag.qregs.values())
global_index_map[wire] = global_qregs.index(wire[0]) + wire[1]
blocks = self.property_set['block_list']
nodes_seen = set()
for node in dag.topological_op_nodes():
# skip already-visited nodes or input/output nodes
if node in nodes_seen or node.type == 'in' or node.type == 'out':
continue
# check if the node belongs to the next block
if blocks and node in blocks[0]:
block = blocks[0]
# find the qubits involved in this block
block_qargs = set()
for nd in block:
block_qargs |= set(nd.qargs)
# convert block to a sub-circuit, then simulate unitary and add
block_width = len(block_qargs)
q = QuantumRegister(block_width)
subcirc = QuantumCircuit(q)
block_index_map = self._block_qargs_to_indices(
block_qargs, global_index_map)
for nd in block:
nodes_seen.add(nd)
subcirc.append(nd.op,
[q[block_index_map[i]] for i in nd.qargs])
unitary = UnitaryGate(
Operator(subcirc)) # simulates the circuit
new_dag.apply_operation_back(
unitary,
sorted(block_qargs, key=lambda x: block_index_map[x]))
del blocks[0]
else:
# the node could belong to some future block, but in that case
# we simply skip it. It is guaranteed that we will revisit that
# future block, via its other nodes
for block in blocks[1:]:
if node in block:
break
# freestanding nodes can just be added
else:
nodes_seen.add(node)
new_dag.apply_operation_back(node.op, node.qargs,
node.cargs)
return new_dag
def num_qubits(self, num_qubits):
self._invalidate()
self._num_qubits = num_qubits
self.qregs = [QuantumRegister(self.num_qubits, name="q")]
def _off_diag_circ(self, theta: float = 1) -> QuantumCircuit:
"""Circuit implementing the matrix consisting of entries in the off diagonals.
Args:
theta: Scale factor for the off diagonal entries (e.g. evolution_time/trotter_steps).
Returns:
The quantum circuit implementing the matrix consisting of entries in the off diagonals.
"""
theta *= self.off_diag
qr = QuantumRegister(self.num_state_qubits)
if self.num_state_qubits > 1:
qr_ancilla = AncillaRegister(max(1, self.num_state_qubits - 2))
qc = QuantumCircuit(qr, qr_ancilla, name="off_diags")
else:
qc = QuantumCircuit(qr, name="off_diags")
qr_ancilla = None
qc.u(-2 * theta, 3 * np.pi / 2, np.pi / 2, qr[0])
for i in range(0, self.num_state_qubits - 1):
q_controls = []
qc.cx(qr[i], qr[i + 1])
q_controls.append(qr[i + 1])
# Now we want controlled by 0
qc.x(qr[i])
for j in range(i, 0, -1):
qc.cx(qr[i], qr[j - 1])
q_controls.append(qr[j - 1])
qc.x(qr[i])
# Multicontrolled rotation
if len(q_controls) > 1:
ugate = UGate(-2 * theta, 3 * np.pi / 2, np.pi / 2)
qc.append(
MCMTVChain(ugate, len(q_controls), 1),
q_controls[:] + [qr[i]] + qr_ancilla[:len(q_controls) - 1],
)
else:
qc.cu(-2 * theta, 3 * np.pi / 2, np.pi / 2, 0, q_controls[0],
qr[i])
# Uncompute
qc.x(qr[i])
for j in range(0, i):
qc.cx(qr[i], qr[j])
qc.x(qr[i])
qc.cx(qr[i], qr[i + 1])
# pylint: disable=unused-argument
def control(num_ctrl_qubits=1, label=None, ctrl_state=None):
qr_state = QuantumRegister(self.num_state_qubits + 1)
if self.num_state_qubits > 1:
qr_ancilla = AncillaRegister(max(1, self.num_state_qubits - 1))
qc_control = QuantumCircuit(qr_state,
qr_ancilla,
name="off_diags")
else:
qc_control = QuantumCircuit(qr_state, name="off_diags")
qr_ancilla = None
# Control will be qr[0]
q_control = qr_state[0]
qr = qr_state[1:]
qc_control.cu(-2 * theta, 3 * np.pi / 2, np.pi / 2, 0, q_control,
qr[0])
for i in range(0, self.num_state_qubits - 1):
q_controls = []
q_controls.append(q_control)
qc_control.cx(qr[i], qr[i + 1])
q_controls.append(qr[i + 1])
# Now we want controlled by 0
qc_control.x(qr[i])
for j in range(i, 0, -1):
qc_control.cx(qr[i], qr[j - 1])
q_controls.append(qr[j - 1])
qc_control.x(qr[i])
# Multicontrolled x rotation
if len(q_controls) > 1:
ugate = UGate(-2 * theta, 3 * np.pi / 2, np.pi / 2)
qc_control.append(
MCMTVChain(ugate, len(q_controls), 1).to_gate(),
q_controls[:] + [qr[i]] +
qr_ancilla[:len(q_controls) - 1],
)
else:
qc_control.cu(-2 * theta, 3 * np.pi / 2, np.pi / 2, 0,
q_controls[0], qr[i])
# Uncompute
qc_control.x(qr[i])
for j in range(0, i):
qc_control.cx(qr[i], qr[j])
qc_control.x(qr[i])
qc_control.cx(qr[i], qr[i + 1])
return qc_control
qc.control = control
return qc
def _compose_transforms(basis_transforms, source_basis, source_dag):
"""Compose a set of basis transforms into a set of replacements.
Args:
basis_transforms (List[Tuple[gate_name, params, equiv]]): List of
transforms to compose.
source_basis (Set[Tuple[gate_name: str, gate_num_qubits: int]]): Names
of gates which need to be translated.
source_dag (DAGCircuit): DAG with example gates from source_basis.
(Used to determine num_params for gate in source_basis.)
Returns:
Dict[gate_name, Tuple(params, dag)]: Dictionary mapping between each gate
in source_basis and a DAGCircuit instance to replace it. Gates in
source_basis but not affected by basis_transforms will be included
as a key mapping to itself.
"""
example_gates = {(node.op.name, node.op.num_qubits): node.op for node in source_dag.op_nodes()}
mapped_instrs = {}
for gate_name, gate_num_qubits in source_basis:
# Need to grab a gate instance to find num_qubits and num_params.
# Can be removed following https://github.com/Qiskit/qiskit-terra/pull/3947 .
example_gate = example_gates[gate_name, gate_num_qubits]
num_params = len(example_gate.params)
placeholder_params = ParameterVector(gate_name, num_params)
placeholder_gate = Gate(gate_name, gate_num_qubits, list(placeholder_params))
placeholder_gate.params = list(placeholder_params)
dag = DAGCircuit()
qr = QuantumRegister(gate_num_qubits)
dag.add_qreg(qr)
dag.apply_operation_back(placeholder_gate, qr[:], [])
mapped_instrs[gate_name, gate_num_qubits] = placeholder_params, dag
for gate_name, gate_num_qubits, equiv_params, equiv in basis_transforms:
logger.debug(
"Composing transform step: %s/%s %s =>\n%s",
gate_name,
gate_num_qubits,
equiv_params,
equiv,
)
for mapped_instr_name, (dag_params, dag) in mapped_instrs.items():
doomed_nodes = [
node
for node in dag.op_nodes()
if (node.op.name, node.op.num_qubits) == (gate_name, gate_num_qubits)
]
if doomed_nodes and logger.isEnabledFor(logging.DEBUG):
from qiskit.converters import dag_to_circuit
logger.debug(
"Updating transform for mapped instr %s %s from \n%s",
mapped_instr_name,
dag_params,
dag_to_circuit(dag),
)
for node in doomed_nodes:
from qiskit.converters import circuit_to_dag
replacement = equiv.assign_parameters(
dict(zip_longest(equiv_params, node.op.params))
)
replacement_dag = circuit_to_dag(replacement)
dag.substitute_node_with_dag(node, replacement_dag)
if doomed_nodes and logger.isEnabledFor(logging.DEBUG):
from qiskit.converters import dag_to_circuit
logger.debug(
"Updated transform for mapped instr %s %s to\n%s",
mapped_instr_name,
dag_params,
dag_to_circuit(dag),
)
return mapped_instrs
def random_circuit(n_qubits,
depth,
coupling_map=None,
basis_gates=None,
prob_one_q_op=0.5,
reset=False,
seed=None):
"""Generate RQC faithfully according to the given coupling_map and basis_gates.
Args:
n_qubits (int): the number of qubits, must > largest qubit label in coupling_map
depth (int): the number of the layers of operations
coupling_map (CouplingMap or list): coupling map specifies allowed CNOTs
default: fully connected graph coupling n_qubits
basis_gates (list): the list of labels of basis gates used in construction
default: all available gates in gate_set
prob_one_q_op (float): the probability of selecting a one-qubit operation when two_q_op is allowed
default: equal probability 0.5
reset (bool): if True, insert middle resets
seed (int): sets random seed (optional)
Returns:
QuantumCircuit: constructed circuit
Raises:
CircuitError: when invalid options given
"""
max_operands = 2
assert max_operands == 2
if isinstance(coupling_map, list):
coupling_map = CouplingMap(coupling_map)
if coupling_map != None and n_qubits < max(
coupling_map.physical_qubits) + 1:
raise CircuitError("n_qubits is not enough to accomodate CouplingMap")
if basis_gates == None:
basis_gates = gate_set
one_q_ops = [
label2gate[name] for name in one_q_ops_label & set(basis_gates)
]
two_q_ops = [
label2gate[name] for name in two_q_ops_label & set(basis_gates)
]
one_param = [
label2gate[name] for name in one_param_label & set(basis_gates)
]
two_param = [
label2gate[name] for name in two_param_label & set(basis_gates)
]
three_param = [
label2gate[name] for name in three_param_label & set(basis_gates)
]
if len(one_q_ops) == 0:
raise CircuitError("no available one-qubit gate")
if len(two_q_ops) == 0:
raise CircuitError("CNOT is not available")
qreg = QuantumRegister(n_qubits, 'q')
qc = QuantumCircuit(n_qubits)
# default coupling_map is fully connected
if coupling_map == None:
coupling_map = CouplingMap.from_full(n_qubits)
if reset:
one_q_ops += [Reset]
if seed is None:
seed = np.random.randint(0, np.iinfo(np.int32).max)
rng = np.random.RandomState(seed)
for _ in range(depth):
remaining_qubits = coupling_map.physical_qubits
remaining_edges = coupling_map.get_edges()
if remaining_edges:
allow_two_q_op = True
while remaining_qubits:
if allow_two_q_op:
max_possible_operands = min(len(remaining_qubits),
max_operands)
else:
max_possible_operands = 1
if max_possible_operands == 1:
possible_operands_set = [1]
num_operands = 1
else:
possible_operands_set = [1, 2]
num_operands = (not (rng.uniform() < prob_one_q_op)) + 1
if num_operands == 1:
operation = rng.choice(one_q_ops)
operands = rng.choice(remaining_qubits)
register_operands = [qreg[int(operands)]]
operands = [operands]
elif num_operands == 2:
operation = rng.choice(two_q_ops)
operands = remaining_edges[rng.choice(
range(len(remaining_edges)))]
register_operands = [qreg[i] for i in operands]
remaining_qubits = [
q for q in remaining_qubits if q not in operands
]
if remaining_edges:
remaining_edges = [
pair for pair in remaining_edges
if pair[0] not in operands and pair[1] not in operands
]
if allow_two_q_op and not remaining_edges:
allow_two_q_op = False
if operation in one_param:
num_angles = 1
elif operation in two_param:
num_angles = 2
elif operation in three_param:
num_angles = 3
else:
num_angles = 0
angles = [rng.uniform(0, 2 * np.pi) for x in range(num_angles)]
op = operation(*angles)
qc.append(op, register_operands)
return qc
def test_add_reg_duplicate(self):
"""add_qreg with the same register twice is not allowed."""
dag = DAGCircuit()
qr = QuantumRegister(2)
dag.add_qreg(qr)
self.assertRaises(DAGCircuitError, dag.add_qreg, qr)
qtest_data_ft3=qtest_data['petal width (cm)']
qtest_data_ft4=[]
qtest_data_ft4=qtest_data['petal width (cm)']
# In[66]:
from qiskit.quantum_info import state_fidelity
# In[67]:
device=Aer.get_backend('qasm_simulator')
q=QuantumRegister(5)
c=ClassicalRegister(5)
cir1=QuantumCircuit(q,c)
cir1.u3(qtrain_data_ft1[2],qtrain_data_ft2[2],0,q[1]) #quantum state training data ft1&ft2
cir1.u3(qtrain_data_ft3[2],qtrain_data_ft4[2],0,q[2]) #quantum state training data ft3&ft4
cir1.u3(qtest_data_ft1[3],qtest_data_ft2[3],0,q[3]) #quantum state testing data ft1&ft2
cir1.u3(qtest_data_ft3[3],qtest_data_ft4[3],0,q[4]) #quantum state testing data ft3&ft4
cir1.barrier()
cir1.h(q[0])
cir1.cswap(q[0],q[1],q[3])
cir1.cswap(q[0],q[2],q[4])
cir1.h(q[0])
cir1.measure(q[0],c[0])
cir1.draw(output='mpl')
def _process_node(self, node):
"""Carry out the action associated with a node."""
if node.type == "program":
self._process_children(node)
elif node.type == "qreg":
qreg = QuantumRegister(node.index, node.name)
self.dag.add_qreg(qreg)
elif node.type == "creg":
creg = ClassicalRegister(node.index, node.name)
self.dag.add_creg(creg)
elif node.type == "id":
raise QiskitError("internal error: _process_node on id")
elif node.type == "int":
raise QiskitError("internal error: _process_node on int")
elif node.type == "real":
raise QiskitError("internal error: _process_node on real")
elif node.type == "indexed_id":
raise QiskitError("internal error: _process_node on indexed_id")
elif node.type == "id_list":
# We process id_list nodes when they are leaves of barriers.
return [self._process_bit_id(node_children)
for node_children in node.children]
elif node.type == "primary_list":
# We should only be called for a barrier.
return [self._process_bit_id(m) for m in node.children]
elif node.type == "gate":
self._process_gate(node)
elif node.type == "custom_unitary":
self._process_custom_unitary(node)
elif node.type == "universal_unitary":
args = self._process_node(node.children[0])
qid = self._process_bit_id(node.children[1])
for element in qid:
u3_gate = U3Gate(*args, element)
u3_gate.condition = self.condition
self.dag.apply_operation_back(u3_gate)
elif node.type == "cnot":
self._process_cnot(node)
elif node.type == "expression_list":
return node.children
elif node.type == "binop":
raise QiskitError("internal error: _process_node on binop")
elif node.type == "prefix":
raise QiskitError("internal error: _process_node on prefix")
elif node.type == "measure":
self._process_measure(node)
elif node.type == "format":
self.version = node.version()
elif node.type == "barrier":
ids = self._process_node(node.children[0])
qubits = []
for qubit in ids:
for j, _ in enumerate(qubit):
qubits.append(qubit[j])
self.dag.apply_operation_back(Barrier(len(qubits)), qubits, [])
elif node.type == "reset":
id0 = self._process_bit_id(node.children[0])
for i, _ in enumerate(id0):
reset = Reset()
reset.condition = self.condition
self.dag.apply_operation_back(reset, [id0[i]], [])
elif node.type == "if":
self._process_if(node)
elif node.type == "opaque":
self._process_gate(node, opaque=True)
elif node.type == "external":
raise QiskitError("internal error: _process_node on external")
else:
raise QiskitError("internal error: undefined node type",
node.type, "line=%s" % node.line,
"file=%s" % node.file)
return None
def construct_circuit(
self, matrix: Union[np.ndarray, QuantumCircuit],
vector: Union[np.ndarray, QuantumCircuit]) -> QuantumCircuit:
"""Construct the HHL circuit.
Args:
matrix: The matrix specifying the system, i.e. A in Ax=b.
vector: The vector specifying the right hand side of the equation in Ax=b.
Returns:
The HHL circuit.
Raises:
ValueError: If the input is not in the correct format.
ValueError: If the type of the input matrix is not supported.
"""
# State preparation circuit - default is qiskit
if isinstance(vector, QuantumCircuit):
nb = vector.num_qubits
vector_circuit = vector
elif isinstance(vector, np.ndarray):
nb = int(np.log2(len(vector)))
vector_circuit = QuantumCircuit(nb)
vector_circuit.isometry(vector / np.linalg.norm(vector),
list(range(nb)), None)
# If state preparation is probabilistic the number of qubit flags should increase
nf = 1
# Hamiltonian simulation circuit - default is Trotterization
if isinstance(matrix, QuantumCircuit):
matrix_circuit = matrix
elif isinstance(matrix, (list, np.ndarray)):
if isinstance(matrix, list):
matrix = np.array(matrix)
if matrix.shape[0] != matrix.shape[1]:
raise ValueError("Input matrix must be square!")
if np.log2(matrix.shape[0]) % 1 != 0:
raise ValueError("Input matrix dimension must be 2^n!")
if not np.allclose(matrix, matrix.conj().T):
raise ValueError("Input matrix must be hermitian!")
if matrix.shape[0] != 2**vector_circuit.num_qubits:
raise ValueError("Input vector dimension does not match input "
"matrix dimension! Vector dimension: " +
str(vector_circuit.num_qubits) +
". Matrix dimension: " + str(matrix.shape[0]))
matrix_circuit = NumPyMatrix(matrix, evolution_time=2 * np.pi)
else:
raise ValueError(f'Invalid type for matrix: {type(matrix)}.')
# Set the tolerance for the matrix approximation
if hasattr(matrix_circuit, "tolerance"):
matrix_circuit.tolerance = self._epsilon_a
# check if the matrix can calculate the condition number and store the upper bound
if hasattr(matrix_circuit, "condition_bounds") and matrix_circuit.condition_bounds() is not\
None:
kappa = matrix_circuit.condition_bounds()[1]
else:
kappa = 1
# Update the number of qubits required to represent the eigenvalues
nl = max(nb + 1, int(np.log2(kappa)) + 1)
# check if the matrix can calculate bounds for the eigenvalues
if hasattr(matrix_circuit,
"eigs_bounds") and matrix_circuit.eigs_bounds() is not None:
lambda_min, lambda_max = matrix_circuit.eigs_bounds()
# Constant so that the minimum eigenvalue is represented exactly, since it contributes
# the most to the solution of the system
delta = self._get_delta(nl, lambda_min, lambda_max)
# Update evolution time
matrix_circuit.evolution_time = 2 * np.pi * delta / lambda_min
# Update the scaling of the solution
self.scaling = lambda_min
else:
delta = 1 / (2**nl)
print("The solution will be calculated up to a scaling factor.")
if self._exact_reciprocal:
reciprocal_circuit = ExactReciprocal(nl, delta)
# Update number of ancilla qubits
na = matrix_circuit.num_ancillas
else:
# Calculate breakpoints for the reciprocal approximation
num_values = 2**nl
constant = delta
a = int(round(num_values**(2 / 3))) # pylint: disable=invalid-name
# Calculate the degree of the polynomial and the number of intervals
r = 2 * constant / a + np.sqrt(np.abs(1 - (2 * constant / a)**2))
degree = min(
nb,
int(
np.log(1 +
(16.23 * np.sqrt(np.log(r)**2 +
(np.pi / 2)**2) * kappa *
(2 * kappa - self._epsilon_r)) / self._epsilon_r)))
num_intervals = int(
np.ceil(np.log((num_values - 1) / a) / np.log(5)))
# Calculate breakpoints and polynomials
breakpoints = []
for i in range(0, num_intervals):
# Add the breakpoint to the list
breakpoints.append(a * (5**i))
# Define the right breakpoint of the interval
if i == num_intervals - 1:
breakpoints.append(num_values - 1)
reciprocal_circuit = PiecewiseChebyshev(
lambda x: np.arcsin(constant / x), degree, breakpoints, nl)
na = max(matrix_circuit.num_ancillas,
reciprocal_circuit.num_ancillas)
# Initialise the quantum registers
qb = QuantumRegister(nb) # right hand side and solution
ql = QuantumRegister(nl) # eigenvalue evaluation qubits
if na > 0:
qa = AncillaRegister(na) # ancilla qubits
qf = QuantumRegister(nf) # flag qubits
if na > 0:
qc = QuantumCircuit(qb, ql, qa, qf)
else:
qc = QuantumCircuit(qb, ql, qf)
# State preparation
qc.append(vector_circuit, qb[:])
# QPE
phase_estimation = PhaseEstimation(nl, matrix_circuit)
if na > 0:
qc.append(phase_estimation,
ql[:] + qb[:] + qa[:matrix_circuit.num_ancillas])
else:
qc.append(phase_estimation, ql[:] + qb[:])
# Conditioned rotation
if self._exact_reciprocal:
qc.append(reciprocal_circuit, ql[::-1] + [qf[0]])
else:
qc.append(reciprocal_circuit.to_instruction(),
ql[:] + [qf[0]] + qa[:reciprocal_circuit.num_ancillas])
# QPE inverse
if na > 0:
qc.append(phase_estimation.inverse(),
ql[:] + qb[:] + qa[:matrix_circuit.num_ancillas])
else:
qc.append(phase_estimation.inverse(), ql[:] + qb[:])
return qc
def random_circuit(n_qubits,
depth,
max_operands=3,
measure=False,
conditional=False,
reset=False,
seed=None):
"""Generate random circuit of arbitrary size and form.
Args:
n_qubits (int): number of quantum wires
depth (int): layers of operations (i.e. critical path length)
max_operands (int): maximum operands of each gate (between 1 and 3)
measure (bool): if True, measure all qubits at the end
conditional (bool): if True, insert middle measurements and conditionals
reset (bool): if True, insert middle resets
seed (int): sets random seed (optional)
Returns:
QuantumCircuit: constructed circuit
Raises:
CircuitError: when invalid options given
"""
if max_operands < 1 or max_operands > 3:
raise CircuitError("max_operands must be between 1 and 3")
one_q_ops = [
IGate, U1Gate, U2Gate, U3Gate, XGate, YGate, ZGate, HGate, SGate,
SdgGate, TGate, TdgGate, RXGate, RYGate, RZGate
]
one_param = [U1Gate, RXGate, RYGate, RZGate, RZZGate, CU1Gate, CRZGate]
two_param = [U2Gate]
three_param = [U3Gate, CU3Gate]
two_q_ops = [
CXGate, CYGate, CZGate, CHGate, CRZGate, CU1Gate, CU3Gate, SwapGate,
RZZGate
]
three_q_ops = [CCXGate, CSwapGate]
qr = QuantumRegister(n_qubits, 'q')
qc = QuantumCircuit(n_qubits)
if measure or conditional:
cr = ClassicalRegister(n_qubits, 'c')
qc.add_register(cr)
if reset:
one_q_ops += [Reset]
if seed is None:
seed = np.random.randint(0, np.iinfo(np.int32).max)
rng = np.random.RandomState(seed)
# apply arbitrary random operations at every depth
for _ in range(depth):
# choose either 1, 2, or 3 qubits for the operation
remaining_qubits = list(range(n_qubits))
while remaining_qubits:
max_possible_operands = min(len(remaining_qubits), max_operands)
num_operands = rng.choice(range(max_possible_operands)) + 1
rng.shuffle(remaining_qubits)
operands = remaining_qubits[:num_operands]
remaining_qubits = [
q for q in remaining_qubits if q not in operands
]
if num_operands == 1:
operation = rng.choice(one_q_ops)
elif num_operands == 2:
operation = rng.choice(two_q_ops)
elif num_operands == 3:
operation = rng.choice(three_q_ops)
if operation in one_param:
num_angles = 1
elif operation in two_param:
num_angles = 2
elif operation in three_param:
num_angles = 3
else:
num_angles = 0
angles = [rng.uniform(0, 2 * np.pi) for x in range(num_angles)]
register_operands = [qr[i] for i in operands]
op = operation(*angles)
# with some low probability, condition on classical bit values
if conditional and rng.choice(range(10)) == 0:
value = rng.randint(0, np.power(2, n_qubits))
op.condition = (cr, value)
qc.append(op, register_operands)
if measure:
qc.measure(qr, cr)
return qc
def test_basic_slice(self):
"""simple slice test"""
qr = QuantumRegister(5)
cr = ClassicalRegister(5)
self.assertEqual(len(qr[0:3]), 3)
self.assertEqual(len(cr[0:3]), 3)
