Update metadata of Primitives V2 (Qiskit#12784)

* update metadata of primitives v2

* remove `shots` and add reno

* add version

* add shots to SamplerV2 metadata

* udpate reno

---------

Co-authored-by: Elena Peña Tapia <[email protected]>

qiskit/primitives/backend_estimator_v2.py

@@ -190,7 +190,7 @@ def _run(self, pubs: list[EstimatorPub]) -> PrimitiveResult[PubResult]:
             # reconstruct the result of pubs
             for i, pub_result in zip(lst, pub_results):
                 results[i] = pub_result
-        return PrimitiveResult(results)
+        return PrimitiveResult(results, metadata={"version": 2})
 
     def _run_pubs(self, pubs: list[EstimatorPub], shots: int) -> list[PubResult]:
         """Compute results for pubs that all require the same value of ``shots``."""
@@ -238,7 +238,6 @@ def _preprocess_pub(self, pub: EstimatorPub) -> _PreprocessedData:
         param_indices = np.fromiter(np.ndindex(param_shape), dtype=object).reshape(param_shape)
         bc_param_ind, bc_obs = np.broadcast_arrays(param_indices, observables)
 
-        # calculate expectation values for each pair of parameter value set and pauli
         param_obs_map = defaultdict(set)
         for index in np.ndindex(*bc_param_ind.shape):
             param_index = bc_param_ind[index]
@@ -275,7 +274,14 @@ def _postprocess_pub(
                 variances[index] += np.abs(coeff) * variance**0.5
         stds = variances / np.sqrt(shots)
         data_bin = DataBin(evs=evs, stds=stds, shape=evs.shape)
-        return PubResult(data_bin, metadata={"target_precision": pub.precision})
+        return PubResult(
+            data_bin,
+            metadata={
+                "target_precision": pub.precision,
+                "shots": shots,
+                "circuit_metadata": pub.circuit.metadata,
+            },
+        )
 
     def _bind_and_add_measurements(
         self,

qiskit/primitives/backend_sampler_v2.py

@@ -155,7 +155,7 @@ def _run(self, pubs: list[SamplerPub]) -> PrimitiveResult[SamplerPubResult]:
             # reconstruct the result of pubs
             for i, pub_result in zip(lst, pub_results):
                 results[i] = pub_result
-        return PrimitiveResult(results)
+        return PrimitiveResult(results, metadata={"version": 2})
 
     def _run_pubs(self, pubs: list[SamplerPub], shots: int) -> list[SamplerPubResult]:
         """Compute results for pubs that all require the same value of ``shots``."""
@@ -183,7 +183,12 @@ def _run_pubs(self, pubs: list[SamplerPub], shots: int) -> list[SamplerPubResult
             end = start + bound.size
             results.append(
                 self._postprocess_pub(
-                    result_memory[start:end], shots, bound.shape, meas_info, max_num_bytes
+                    result_memory[start:end],
+                    shots,
+                    bound.shape,
+                    meas_info,
+                    max_num_bytes,
+                    pub.circuit.metadata,
                 )
             )
             start = end
@@ -197,6 +202,7 @@ def _postprocess_pub(
         shape: tuple[int, ...],
         meas_info: list[_MeasureInfo],
         max_num_bytes: int,
+        circuit_metadata: dict,
     ) -> SamplerPubResult:
         """Converts the memory data into an array of bit arrays with the shape of the pub."""
         arrays = {
@@ -213,7 +219,10 @@ def _postprocess_pub(
         meas = {
             item.creg_name: BitArray(arrays[item.creg_name], item.num_bits) for item in meas_info
         }
-        return SamplerPubResult(DataBin(**meas, shape=shape), metadata={})
+        return SamplerPubResult(
+            DataBin(**meas, shape=shape),
+            metadata={"shots": shots, "circuit_metadata": circuit_metadata},
+        )
 
 
 def _analyze_circuit(circuit: QuantumCircuit) -> tuple[list[_MeasureInfo], int]:

qiskit/primitives/statevector_estimator.py

@@ -136,7 +136,7 @@ def run(
         return job
 
     def _run(self, pubs: list[EstimatorPub]) -> PrimitiveResult[PubResult]:
-        return PrimitiveResult([self._run_pub(pub) for pub in pubs])
+        return PrimitiveResult([self._run_pub(pub) for pub in pubs], metadata={"version": 2})
 
     def _run_pub(self, pub: EstimatorPub) -> PubResult:
         rng = np.random.default_rng(self._seed)
@@ -162,4 +162,6 @@ def _run_pub(self, pub: EstimatorPub) -> PubResult:
             evs[index] = expectation_value
 
         data = DataBin(evs=evs, stds=stds, shape=evs.shape)
-        return PubResult(data, metadata={"precision": precision})
+        return PubResult(
+            data, metadata={"target_precision": precision, "circuit_metadata": pub.circuit.metadata}
+        )

qiskit/primitives/statevector_sampler.py

@@ -171,7 +171,7 @@ def run(
 
     def _run(self, pubs: Iterable[SamplerPub]) -> PrimitiveResult[SamplerPubResult]:
         results = [self._run_pub(pub) for pub in pubs]
-        return PrimitiveResult(results)
+        return PrimitiveResult(results, metadata={"version": 2})
 
     def _run_pub(self, pub: SamplerPub) -> SamplerPubResult:
         circuit, qargs, meas_info = _preprocess_circuit(pub.circuit)
@@ -197,7 +197,10 @@ def _run_pub(self, pub: SamplerPub) -> SamplerPubResult:
         meas = {
             item.creg_name: BitArray(arrays[item.creg_name], item.num_bits) for item in meas_info
         }
-        return SamplerPubResult(DataBin(**meas, shape=pub.shape), metadata={"shots": pub.shots})
+        return SamplerPubResult(
+            DataBin(**meas, shape=pub.shape),
+            metadata={"shots": pub.shots, "circuit_metadata": pub.circuit.metadata},
+        )
 
 
 def _preprocess_circuit(circuit: QuantumCircuit):

releasenotes/notes/update-primitive-v2-metadata-cf1226e2d6477688.yaml

@@ -0,0 +1,13 @@
+---
+features_primitives:
+  - |
+    The metadata of Primitives V2 implementations, i.e., :class:`.StatevectorSampler`,
+    :class:`.StatevectorEstimator`, :class:`.BackendSamplerV2` and :class:`.BackendEstimatorV2`,
+    has been updated to match that of IBM quantum devices.
+
+    * ``version`` and ``circuit_metadata`` are added for all V2 implementations
+    * ``shots`` is added for :class:`.BackendSamplerV2` and :class:`.BackendEstimatorV2`
+    * ``precision`` is renamed with ``target_precision`` for :class:`.StatevectorEstimator`
+
+    Note that metadata of :class:`.StatevectorEstimator` does not have ``shots`` because
+    the class computes expectation values with :class:`.Statevector` and shots are not used.

test/python/primitives/test_backend_estimator_v2.py

@@ -474,6 +474,30 @@ def test_iter_pub(self):
         np.testing.assert_allclose(result[0].data.evs, [-1.284366511861733], rtol=self._rtol)
         np.testing.assert_allclose(result[1].data.evs, [-1.284366511861733], rtol=self._rtol)
 
+    def test_metadata(self):
+        """Test for metadata"""
+        qc = QuantumCircuit(2)
+        qc2 = QuantumCircuit(2)
+        qc2.metadata = {"a": 1}
+        backend = BasicSimulator()
+        estimator = BackendEstimatorV2(backend=backend)
+        pm = generate_preset_pass_manager(optimization_level=0, backend=backend)
+        qc, qc2 = pm.run([qc, qc2])
+        op = SparsePauliOp("ZZ").apply_layout(qc.layout)
+        op2 = SparsePauliOp("ZZ").apply_layout(qc2.layout)
+        result = estimator.run([(qc, op), (qc2, op2)], precision=0.1).result()
+
+        self.assertEqual(len(result), 2)
+        self.assertEqual(result.metadata, {"version": 2})
+        self.assertEqual(
+            result[0].metadata,
+            {"target_precision": 0.1, "shots": 100, "circuit_metadata": qc.metadata},
+        )
+        self.assertEqual(
+            result[1].metadata,
+            {"target_precision": 0.1, "shots": 100, "circuit_metadata": qc2.metadata},
+        )
+
 
 if __name__ == "__main__":
     unittest.main()

test/python/primitives/test_backend_sampler_v2.py

@@ -748,6 +748,21 @@ def test_iter_pub(self):
         self._assert_allclose(result[0].data.meas, np.array({0: self._shots}))
         self._assert_allclose(result[1].data.meas, np.array({1: self._shots}))
 
+    def test_metadata(self):
+        """Test for metadata"""
+        qc = QuantumCircuit(2)
+        qc.measure_all()
+        qc2 = qc.copy()
+        qc2.metadata = {"a": 1}
+        backend = BasicSimulator()
+        sampler = BackendSamplerV2(backend=backend)
+        result = sampler.run([(qc, None, 10), (qc2, None, 20)]).result()
+
+        self.assertEqual(len(result), 2)
+        self.assertEqual(result.metadata, {"version": 2})
+        self.assertEqual(result[0].metadata, {"shots": 10, "circuit_metadata": qc.metadata})
+        self.assertEqual(result[1].metadata, {"shots": 20, "circuit_metadata": qc2.metadata})
+
 
 if __name__ == "__main__":
     unittest.main()

test/python/primitives/test_statevector_estimator.py

@@ -129,7 +129,7 @@ def test_run_single_circuit_observable(self):
                 self.subTest(f"{val}")
                 result = est.run([(qc, op, val)]).result()
                 np.testing.assert_allclose(result[0].data.evs, target)
-                self.assertEqual(result[0].metadata["precision"], 0)
+                self.assertEqual(result[0].metadata["target_precision"], 0)
 
         with self.subTest("One parameter"):
             param = Parameter("x")
@@ -145,7 +145,7 @@ def test_run_single_circuit_observable(self):
                 self.subTest(f"{val}")
                 result = est.run([(qc, op, val)]).result()
                 np.testing.assert_allclose(result[0].data.evs, target)
-                self.assertEqual(result[0].metadata["precision"], 0)
+                self.assertEqual(result[0].metadata["target_precision"], 0)
 
         with self.subTest("More than one parameter"):
             qc = self.psi[0]
@@ -162,7 +162,7 @@ def test_run_single_circuit_observable(self):
                 self.subTest(f"{val}")
                 result = est.run([(qc, op, val)]).result()
                 np.testing.assert_allclose(result[0].data.evs, target)
-                self.assertEqual(result[0].metadata["precision"], 0)
+                self.assertEqual(result[0].metadata["target_precision"], 0)
 
     def test_run_1qubit(self):
         """Test for 1-qubit cases"""
@@ -290,6 +290,23 @@ def test_iter_pub(self):
         np.testing.assert_allclose(result[0].data.evs, [-1.284366511861733])
         np.testing.assert_allclose(result[1].data.evs, [-1.284366511861733])
 
+    def test_metadata(self):
+        """Test for metadata"""
+        qc = QuantumCircuit(2)
+        qc2 = QuantumCircuit(2)
+        qc2.metadata = {"a": 1}
+        estimator = StatevectorEstimator()
+        result = estimator.run([(qc, "ZZ"), (qc2, "ZZ")], precision=0.1).result()
+
+        self.assertEqual(len(result), 2)
+        self.assertEqual(result.metadata, {"version": 2})
+        self.assertEqual(
+            result[0].metadata, {"target_precision": 0.1, "circuit_metadata": qc.metadata}
+        )
+        self.assertEqual(
+            result[1].metadata, {"target_precision": 0.1, "circuit_metadata": qc2.metadata}
+        )
+
 
 if __name__ == "__main__":
     unittest.main()

test/python/primitives/test_statevector_sampler.py

@@ -648,6 +648,20 @@ def test_iter_pub(self):
         self._assert_allclose(result[0].data.meas, np.array({0: self._shots}))
         self._assert_allclose(result[1].data.meas, np.array({1: self._shots}))
 
+    def test_metadata(self):
+        """Test for metadata"""
+        qc = QuantumCircuit(2)
+        qc.measure_all()
+        qc2 = qc.copy()
+        qc2.metadata = {"a": 1}
+        sampler = StatevectorSampler()
+        result = sampler.run([(qc, None, 10), (qc2, None, 20)]).result()
+
+        self.assertEqual(len(result), 2)
+        self.assertEqual(result.metadata, {"version": 2})
+        self.assertEqual(result[0].metadata, {"shots": 10, "circuit_metadata": qc.metadata})
+        self.assertEqual(result[1].metadata, {"shots": 20, "circuit_metadata": qc2.metadata})
+
 
 if __name__ == "__main__":
     unittest.main()