def run(self, dag):
"""Run the Optimize1qGatesDecomposition pass on `dag`.
Args:
dag (DAGCircuit): the DAG to be optimized.
Returns:
DAGCircuit: the optimized DAG.
"""
if not self.basis:
logger.info("Skipping pass because no basis is set")
return dag
runs = dag.collect_1q_runs()
identity_matrix = np.eye(2)
for run in runs:
single_u3 = False
# Don't try to optimize a single 1q gate, except for U3
if len(run) <= 1:
params = run[0].op.params
# Remove single identity gates
if len(params) > 0 and np.array_equal(run[0].op.to_matrix(),
identity_matrix):
dag.remove_op_node(run[0])
continue
if (isinstance(run[0].op, U3Gate)
and np.isclose(float(params[0]), [0, np.pi / 2],
atol=1e-12,
rtol=0).any()):
single_u3 = True
else:
continue
new_circs = []
operator = Operator(run[0].op)
for gate in run[1:]:
operator = operator.compose(gate.op)
for decomposer in self.basis:
new_circs.append(decomposer(operator))
if new_circs:
new_circ = min(new_circs, key=len)
if (len(run) > len(new_circ)
or (single_u3 and new_circ.data[0][0].name != 'u3')):
new_dag = circuit_to_dag(new_circ)
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)
return dag
def run(self, dag):
"""Run the Optimize1qGatesDecomposition pass on `dag`.
Args:
dag (DAGCircuit): the DAG to be optimized.
Returns:
DAGCircuit: the optimized DAG.
"""
if not self.basis:
logger.info("Skipping pass because no basis is set")
return dag
runs = dag.collect_1q_runs()
identity_matrix = np.eye(2)
for run in runs:
# Don't try to optimize a single 1q gate
if len(run) <= 1:
params = run[0].op.params
# Remove single identity gates
if len(params) > 0 and np.array_equal(run[0].op.to_matrix(),
identity_matrix):
dag.remove_op_node(run[0])
continue
new_circs = []
operator = Operator(run[0].op)
for gate in run[1:]:
operator = operator.compose(gate.op)
for decomposer in self.basis:
new_circs.append(decomposer(operator))
if new_circs:
new_circ = min(new_circs, key=len)
if len(run) > len(new_circ):
new_dag = circuit_to_dag(new_circ)
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)
return dag
