Add fast transpilation method to BaseExperiment

Author: wshanks

qiskit_experiments/calibration_management/base_calibration_experiment.py

@@ -21,19 +21,13 @@
 from qiskit import QuantumCircuit
 from qiskit.providers.options import Options
 from qiskit.pulse import ScheduleBlock
-from qiskit.transpiler import StagedPassManager, PassManager, Layout, CouplingMap
-from qiskit.transpiler.passes import (
-    EnlargeWithAncilla,
-    FullAncillaAllocation,
-    ApplyLayout,
-    SetLayout,
-)
 
 from qiskit_experiments.calibration_management.calibrations import Calibrations
 from qiskit_experiments.calibration_management.update_library import BaseUpdater
 from qiskit_experiments.framework.base_analysis import BaseAnalysis
 from qiskit_experiments.framework.base_experiment import BaseExperiment
 from qiskit_experiments.framework.experiment_data import ExperimentData
+from qiskit_experiments.framework.transpilation import map_qubits, minimal_transpile
 from qiskit_experiments.exceptions import CalibrationError
 
 LOG = logging.getLogger(__name__)
@@ -198,20 +192,6 @@ def _default_experiment_options(cls) -> Options:
         options.update_options(result_index=-1, group="default")
         return options
 
-    @classmethod
-    def _default_transpile_options(cls) -> Options:
-        """Return empty default transpile options as optimization_level is not used."""
-        return Options()
-
-    def set_transpile_options(self, **fields):
-        r"""Add a warning message.
-
-        .. note::
-            If your experiment has overridden `_transpiled_circuits` and needs
-            transpile options then please also override `set_transpile_options`.
-        """
-        warnings.warn(f"Transpile options are not used in {self.__class__.__name__ }.")
-
     def update_calibrations(self, experiment_data: ExperimentData):
         """Update parameter values in the :class:`.Calibrations` instance.
 
@@ -295,42 +275,13 @@ def _transpiled_circuits(self) -> List[QuantumCircuit]:
         Returns:
             A list of transpiled circuits.
         """
-        transpiled = []
-        for circ in self.circuits():
-            circ = self._map_to_physical_qubits(circ)
+        circuits = [map_qubits(c, self.physical_qubits) for c in self.circuits()]
+        for circ in circuits:
             self._attach_calibrations(circ)
-
-            transpiled.append(circ)
+        transpiled = minimal_transpile(circuits, self.backend, self.transpile_options)
 
         return transpiled
 
-    def _map_to_physical_qubits(self, circuit: QuantumCircuit) -> QuantumCircuit:
-        """Map program qubits to physical qubits.
-
-        Args:
-            circuit: The quantum circuit to map to device qubits.
-
-        Returns:
-            A quantum circuit that has the same number of qubits as the backend and where
-            the physical qubits of the experiment have been properly mapped.
-        """
-        initial_layout = Layout.from_intlist(list(self.physical_qubits), *circuit.qregs)
-
-        coupling_map = self._backend_data.coupling_map
-        if coupling_map is not None:
-            coupling_map = CouplingMap(self._backend_data.coupling_map)
-
-        layout = PassManager(
-            [
-                SetLayout(initial_layout),
-                FullAncillaAllocation(coupling_map),
-                EnlargeWithAncilla(),
-                ApplyLayout(),
-            ]
-        )
-
-        return StagedPassManager(["layout"], layout=layout).run(circuit)
-
     @abstractmethod
     def _attach_calibrations(self, circuit: QuantumCircuit):
         """Attach the calibrations to the quantum circuit.

qiskit_experiments/framework/base_experiment.py

@@ -13,18 +13,23 @@
 Base Experiment class.
 """
 
-from abc import ABC, abstractmethod
 import copy
+from abc import ABC, abstractmethod
 from collections import OrderedDict
 from typing import Sequence, Optional, Tuple, List, Dict, Union
 
-from qiskit import transpile, QuantumCircuit
+from qiskit import QuantumCircuit
 from qiskit.providers import Job, Backend
 from qiskit.exceptions import QiskitError
 from qiskit.qobj.utils import MeasLevel
 from qiskit.providers.options import Options
 from qiskit_experiments.framework import BackendData
 from qiskit_experiments.framework.store_init_args import StoreInitArgs
+from qiskit_experiments.framework.transpilation import (
+    DEFAULT_TRANSPILE_OPTIONS,
+    map_qubits,
+    minimal_transpile,
+)
 from qiskit_experiments.framework.base_analysis import BaseAnalysis
 from qiskit_experiments.framework.experiment_data import ExperimentData
 from qiskit_experiments.framework.configs import ExperimentConfig
@@ -373,9 +378,8 @@ def _transpiled_circuits(self) -> List[QuantumCircuit]:
 
         This function can be overridden to define custom transpilation.
         """
-        transpile_opts = copy.copy(self.transpile_options.__dict__)
-        transpile_opts["initial_layout"] = list(self.physical_qubits)
-        transpiled = transpile(self.circuits(), self.backend, **transpile_opts)
+        circuits = [map_qubits(c, self.physical_qubits) for c in self.circuits()]
+        transpiled = minimal_transpile(circuits, self.backend, self.transpile_options)
 
         return transpiled
 
@@ -418,11 +422,36 @@ def set_experiment_options(self, **fields):
 
     @classmethod
     def _default_transpile_options(cls) -> Options:
-        """Default transpiler options for transpilation of circuits"""
+        """Default transpiler options for transpilation of circuits
+
+        Transpile Options:
+            optimization_level (int): Optimization level to pass to
+                :func:`qiskit.transpile`.
+            num_processes (int): Number of processes to use during
+                transpilation on Qiskit >= 1.0.
+            full_transpile (bool): If ``True``,
+                ``BaseExperiment._transpiled_circuits`` (called by
+                :meth:`BaseExperiment.run` if not overridden by a subclass)
+                will call :func:`qiskit.transpile` on the output of
+                :meth:`BaseExperiment.circuits` before executing the circuits.
+                If ``False``, ``BaseExperiment._transpiled_circuits`` will
+                reindex the qubits in the output of
+                :meth:`BaseExperiment.circuits` using the experiments'
+                :meth:`BaseExperiment.physical_qubits`.  Then it will check if
+                the circuit operations are all defined in the
+                :class:`qiskit.transpiler.Target` of the experiment's backend
+                or in the indiivdual circuit calibrations. If not, it will use
+                :class:`qiskit.transpiler.passes.BasisTranslator` to map the
+                circuit instructions to the backend. Additionally,
+                the :class:`qiskit.transpiler.passes.PulseGates` transpiler
+                pass will be run if the :class:`qiskit.transpiler.Target`
+                contains any custom pulse gate calibrations.
+
+        """
         # Experiment subclasses can override this method if they need
         # to set specific default transpiler options to transpile the
         # experiment circuits.
-        return Options(optimization_level=0)
+        return copy.copy(DEFAULT_TRANSPILE_OPTIONS)
 
     @property
     def transpile_options(self) -> Options:

qiskit_experiments/framework/experiment_data.py

@@ -866,11 +866,10 @@ def _add_job_data(
                 LOG.warning("Job was cancelled before completion [Job ID: %s]", jid)
                 return jid, False
             if status == JobStatus.ERROR:
-                LOG.error(
-                    "Job data not added for errored job [Job ID: %s]\nError message: %s",
-                    jid,
-                    job.error_message(),
-                )
+                msg = f"Job data not added for errored job [Job ID: {jid}]"
+                if hasattr(job, "error_message"):
+                    msg += f"\nError message: {job.error_message()}"
+                LOG.error(msg)
                 return jid, False
             LOG.warning("Adding data from job failed [Job ID: %s]", job.job_id())
             raise ex