def test_move_measurements(self):
"""Measurements applied AFTER swap mapping.
"""
backend = FakeQX5BackEnd()
cmap = backend.configuration().coupling_map
circ = QuantumCircuit.from_qasm_file(
self._get_resource_path('qasm/move_measurements.qasm'))
dag_circuit = DAGCircuit.fromQuantumCircuit(circ)
lay = {
('qa', 0): ('q', 0),
('qa', 1): ('q', 1),
('qb', 0): ('q', 15),
('qb', 1): ('q', 2),
('qb', 2): ('q', 14),
('qN', 0): ('q', 3),
('qN', 1): ('q', 13),
('qN', 2): ('q', 4),
('qc', 0): ('q', 12),
('qNt', 0): ('q', 5),
('qNt', 1): ('q', 11),
('qt', 0): ('q', 6)
}
out_dag = transpile_dag(dag_circuit,
initial_layout=lay,
coupling_map=cmap,
format='dag')
moved_meas = remove_last_measurements(out_dag, perform_remove=False)
meas_nodes = out_dag.get_named_nodes('measure')
self.assertEqual(len(moved_meas), len(meas_nodes))
def test_optimize_1q_gates_collapse_identity(self):
"""test optimize_1q_gates removes u1(2*pi) rotations.
See: https://github.com/Qiskit/qiskit-terra/issues/159
"""
qr = QuantumRegister(2, 'qr')
cr = ClassicalRegister(2, 'cr')
qc = QuantumCircuit(qr, cr)
qc.h(qr[0])
qc.cx(qr[1], qr[0])
qc.u1(2 * sympy.pi,
qr[0]) # TODO: this identity should be removed (but is not)
qc.cx(qr[1], qr[0])
qc.u1(sympy.pi / 2, qr[0]) # these three should combine
qc.u1(sympy.pi, qr[0]) # to identity then
qc.u1(sympy.pi / 2, qr[0]) # optimized away.
qc.cx(qr[1], qr[0])
qc.u1(np.pi, qr[1]) # this doesn't become precisely 0, so should
qc.u1(np.pi,
qr[1]) # combine but stay, until an approximate optimizer.
qc.measure(qr[0], cr[0])
qc.measure(qr[1], cr[1])
dag = DAGCircuit.fromQuantumCircuit(qc)
simplified_dag = mapper.optimize_1q_gates(dag)
num_u1_gates_remaining = len(simplified_dag.get_named_nodes('u1'))
self.assertEqual(num_u1_gates_remaining, 2)
def circuit_to_dag(circuit):
"""Build a ``DAGCircuit`` object from a ``QuantumCircuit``.
Args:
circuit (QuantumCircuit): the input circuit.
Return:
DAGCircuit: the DAG representing the input circuit.
"""
dagcircuit = DAGCircuit()
dagcircuit.name = circuit.name
for register in circuit.qregs:
dagcircuit.add_qreg(register)
for register in circuit.cregs:
dagcircuit.add_creg(register)
for main_instruction in circuit.data:
# TODO: generate nodes for CompositeGates;
# for now simply drop their instructions into the DAG
instruction_list = []
is_composite = isinstance(main_instruction, CompositeGate)
if is_composite:
instruction_list = main_instruction.instruction_list()
else:
instruction_list.append(main_instruction)
for instruction in instruction_list:
# Get arguments for classical control (if any)
if instruction.control is None:
control = None
else:
control = (instruction.control[0], instruction.control[1])
def duplicate_instruction(inst):
"""Create a fresh instruction from an input instruction."""
if inst.name == 'barrier':
params = [inst.qargs]
elif inst.name == 'snapshot':
params = inst.params + [inst.qargs]
else:
params = inst.params + inst.qargs + inst.cargs
new_inst = inst.__class__(*params)
return new_inst
inst = duplicate_instruction(instruction)
dagcircuit.apply_operation_back(inst, inst.qargs, inst.cargs,
control)
return dagcircuit
def test_optimize_1q_gates_symbolic(self):
"""optimizes single qubit gate sequences with symbolic params.
See: https://github.com/Qiskit/qiskit-terra/issues/172
"""
qr = QuantumRegister(4)
cr = ClassicalRegister(4)
circ = QuantumCircuit(qr, cr)
# unary
circ.u1(-sympy.pi, qr[0])
circ.u1(-sympy.pi / 2, qr[0])
# binary
circ.u1(0.2 * sympy.pi + 0.3 * sympy.pi, qr[1])
circ.u1(1.3 - 0.3, qr[1])
circ.u1(0.1 * sympy.pi / 2, qr[1])
# extern
circ.u1(sympy.sin(0.2 + 0.3 - sympy.pi), qr[2])
# power
circ.u1(sympy.pi, qr[3])
circ.u1(0.3 + (-sympy.pi)**2, qr[3])
dag = DAGCircuit.fromQuantumCircuit(circ)
simplified_dag = mapper.optimize_1q_gates(dag)
params = set()
for n in simplified_dag.multi_graph.nodes:
node = simplified_dag.multi_graph.node[n]
if node['name'] == 'u1':
params.add(node['op'].param[0])
expected_params = {
-3 * sympy.pi / 2, 1.0 + 0.55 * sympy.pi,
sympy.N(-0.479425538604203), 0.3 + sympy.pi + sympy.pi**2
}
self.assertEqual(params, expected_params)
def circuit_to_dag(circuit):
"""Build a ``DAGCircuit`` object from a ``QuantumCircuit``.
Args:
circuit (QuantumCircuit): the input circuit.
Return:
DAGCircuit: the DAG representing the input circuit.
"""
dagcircuit = DAGCircuit()
dagcircuit.name = circuit.name
for register in circuit.qregs:
dagcircuit.add_qreg(register)
for register in circuit.cregs:
dagcircuit.add_creg(register)
# Add user gate definitions
for name, data in circuit.definitions.items():
dagcircuit.add_basis_element(name, data["n_bits"], 0, data["n_args"])
dagcircuit.add_gate_data(name, data)
# Add instructions
builtins = {
"U": ["U", 1, 0, 3],
"CX": ["CX", 2, 0, 0],
"measure": ["measure", 1, 1, 0],
"reset": ["reset", 1, 0, 0],
"barrier": ["barrier", -1, 0, 0]
}
# Add simulator instructions
simulator_instructions = {
"snapshot": ["snapshot", -1, 0, 1],
"save": ["save", -1, 0, 1],
"load": ["load", -1, 0, 1],
"noise": ["noise", -1, 0, 1]
}
for main_instruction in circuit.data:
# TODO: generate definitions and nodes for CompositeGates,
# for now simply drop their instructions into the DAG
instruction_list = []
is_composite = isinstance(main_instruction, CompositeGate)
if is_composite:
instruction_list = main_instruction.instruction_list()
else:
instruction_list.append(main_instruction)
for instruction in instruction_list:
# Add OpenQASM built-in gates on demand
if instruction.name in builtins:
dagcircuit.add_basis_element(*builtins[instruction.name])
# Add simulator extension instructions
if instruction.name in simulator_instructions:
dagcircuit.add_basis_element(
*simulator_instructions[instruction.name])
# Get arguments for classical control (if any)
if instruction.control is None:
control = None
else:
control = (instruction.control[0], instruction.control[1])
def duplicate_instruction(inst):
"""Create a fresh instruction from an input instruction."""
if inst.name == 'barrier':
params = [inst.qargs]
elif inst.name in simulator_instructions.keys():
params = inst.params + [inst.qargs] + [inst.circuit]
else:
params = inst.params + inst.qargs + inst.cargs
new_inst = inst.__class__(*params)
return new_inst
inst = duplicate_instruction(instruction)
dagcircuit.apply_operation_back(inst, inst.qargs, inst.cargs,
control)
return dagcircuit
def circuit_to_dag(circuit, expand_gates=True):
"""Build a ``DAGCircuit`` object from a ``QuantumCircuit``.
Args:
circuit (QuantumCircuit): the input circuit.
expand_gates (bool): if ``False``, none of the gates are expanded,
i.e. the gates that are defined in the circuit are included in
the DAG basis.
Return:
DAGCircuit: the DAG representing the input circuit.
"""
circuit = copy.deepcopy(circuit)
dagcircuit = DAGCircuit()
dagcircuit.name = circuit.name
for register in circuit.qregs:
dagcircuit.add_qreg(register)
for register in circuit.cregs:
dagcircuit.add_creg(register)
# Add user gate definitions
for name, data in circuit.definitions.items():
dagcircuit.add_basis_element(name, data["n_bits"], 0, data["n_args"])
dagcircuit.add_gate_data(name, data)
# Add instructions
builtins = {
"U": ["U", 1, 0, 3],
"CX": ["CX", 2, 0, 0],
"measure": ["measure", 1, 1, 0],
"reset": ["reset", 1, 0, 0],
"barrier": ["barrier", -1, 0, 0]
}
# Add simulator instructions
simulator_instructions = {
"snapshot": ["snapshot", -1, 0, 1],
"save": ["save", -1, 0, 1],
"load": ["load", -1, 0, 1],
"noise": ["noise", -1, 0, 1]
}
for main_instruction in circuit.data:
# TODO: generate definitions and nodes for CompositeGates,
# for now simply drop their instructions into the DAG
instruction_list = []
is_composite = isinstance(main_instruction, CompositeGate)
if is_composite and expand_gates:
instruction_list = main_instruction.instruction_list()
else:
instruction_list.append(main_instruction)
for instruction in instruction_list:
# Add OpenQASM built-in gates on demand
if instruction.name in builtins:
dagcircuit.add_basis_element(*builtins[instruction.name])
# Add simulator extension instructions
if instruction.name in simulator_instructions:
dagcircuit.add_basis_element(
*simulator_instructions[instruction.name])
# Get arguments for classical control (if any)
if instruction.control is None:
control = None
else:
control = (instruction.control[0], instruction.control[1])
dagcircuit.apply_operation_back(instruction, instruction.qargs,
instruction.cargs, control)
return dagcircuit