Physics simulation for Qiskit circuits

.pre-commit-config.yaml

@@ -1,22 +1,16 @@
 repos:
 -   repo: https://github.com/ambv/black
-    rev: 21.5b1
+    rev: 21.12b0
     hooks:
     - id: black
       language_version: python3
 -   repo: https://github.com/pycqa/flake8
-    rev: 3.9.2
+    rev: 4.0.1
     hooks:
     - id: flake8
 -   repo: https://github.com/pre-commit/mirrors-mypy
-    rev: 'v0.812'
+    rev: 'v0.930'
     hooks:
     - id: mypy
       args: [--no-strict-optional, --ignore-missing-imports]
-      additional_dependencies: [cma==3.0.3,
-                                numpy==1.19.5, 
-                                scipy==1.5.2,
-                                tensorflow==2.4.2, 
-                                tensorflow-probability==0.12.1, 
-                                tensorflow-estimator==2.4.0
-                                ]
+

CHANGELOG.md

@@ -9,6 +9,12 @@ This Changelog tracks all past changes to this project as well as details about
 - `fixed` for any bug fixes.
 - `security` in case of vulnerabilities.
 
+## Upcoming Version
+
+### Details
+
+- `added` proper physics simulation of circuits using qiskit interface #165
+
 ## Version `1.4` - 23 Dec 2021
 
 ### Summary

c3/experiment.py

@@ -152,7 +152,7 @@ def quick_setup(self, cfg) -> None:
             qubit_1 = model.subsystems[props["qubit_1"]]
             qubit_2 = model.subsystems[props["qubit_2"]]
             instr = Instruction(
-                name=gate_name,
+                name=props["name"],
                 targets=[
                     model.names.index(props["qubit_1"]),
                     model.names.index(props["qubit_2"]),

c3/libraries/propagation.py

@@ -165,7 +165,7 @@ def _get_hs_of_t_ts(
     ts = tf.constant(tf.math.reduce_mean(ts_list, axis=0))
     if not np.all(tf.math.reduce_variance(ts_list, axis=0) < 1e-5 * (ts[1] - ts[0])):
         raise Exception("C3Error:Something with the times happend.")
-    if not np.all(tf.math.reduce_variance(ts[1:] - ts[:-1]) < 1e-5 * (ts[1] - ts[0])):
+    if not np.all(tf.math.reduce_variance(ts[1:] - ts[:-1]) < 1e-5 * (ts[1] - ts[0])):  # type: ignore
         raise Exception("C3Error:Something with the times happend.")
 
     dt = tf.constant(ts[1 * prop_res].numpy() - ts[0].numpy(), dtype=tf.complex128)
@@ -263,7 +263,7 @@ def pwc(model: Model, gen: Generator, instr: Instruction) -> Dict:
         ):
             raise Exception("C3Error:Something with the times happend.")
         if not np.all(
-            tf.math.reduce_variance(ts[1:] - ts[:-1]) < 1e-5 * (ts[1] - ts[0])
+            tf.math.reduce_variance(ts[1:] - ts[:-1]) < 1e-5 * (ts[1] - ts[0])  # type: ignore
         ):
             raise Exception("C3Error:Something with the times happend.")
 

c3/qiskit/c3_backend.py

@@ -375,8 +375,8 @@ def run_experiment(self, experiment: QasmQobjExperiment) -> Dict[str, Any]:
 
         # initialise parameters
         self._number_of_qubits = len(pmap.model.subsystems)
-        if self._number_of_qubits != experiment.config.n_qubits:
-            raise C3QiskitError("Number of qubits in Circuit & Device don't match")
+        if self._number_of_qubits < experiment.config.n_qubits:
+            raise C3QiskitError("Not enough qubits on device to run circuit")
 
         shots = self._shots
 
@@ -453,7 +453,6 @@ def run_experiment(self, experiment: QasmQobjExperiment) -> Dict[str, Any]:
 
 
 class C3QasmPhysicsSimulator(C3QasmSimulator):
-    # TODO Boilerplate code. This simulator is not yet implemented.
     """A C3-based perfect gates simulator for Qiskit
 
     Parameters
@@ -474,9 +473,12 @@ class C3QasmPhysicsSimulator(C3QasmSimulator):
         "open_pulse": False,
         "memory": False,
         "max_shots": 65536,
-        "coupling_map": None,
+        "coupling_map": None,  # TODO Coupling map from config file
         "description": "A physics based c3 simulator for qasm experiments",
-        "basis_gates": [],  # TODO add basis gates
+        "basis_gates": [  # TODO Basis gates from config file
+            "cx",
+            "x",
+        ],
         "gates": [],
     }
 
@@ -544,14 +546,15 @@ def run_experiment(self, experiment: QasmQobjExperiment) -> Dict[str, Any]:
 
         # setup C3 Experiment
         exp = Experiment()
-        exp.quick_setup(self._device_config)
+        exp.load_quick_setup(self._device_config)
+        exp.enable_qasm()
+        exp.compute_propagators()  # TODO only simulate qubits used in circuit
         pmap = exp.pmap
-        model = pmap.model  # noqa
 
         # initialise parameters
         self._number_of_qubits = len(pmap.model.subsystems)
-        if self._number_of_qubits != experiment.config.n_qubits:
-            raise C3QiskitError("Number of qubits in Circuit & Device dont match")
+        if self._number_of_qubits < experiment.config.n_qubits:
+            raise C3QiskitError("Not enough qubits on device to run circuit")
 
         shots = self._shots  # noqa
 
@@ -564,24 +567,22 @@ def run_experiment(self, experiment: QasmQobjExperiment) -> Dict[str, Any]:
         # TODO set simulator seed, check qiskit python qasm simulator
         # qiskit-terra/qiskit/providers/basicaer/qasm_simulator.py
         seed_simulator = 2441129
+        instructions_list = [
+            instruction.to_dict() for instruction in experiment.instructions
+        ]
 
-        # convert qasm instruction set to c3 sequence
-        sequence = get_sequence(experiment.instructions)  # noqa
-
-        # TODO get_init_ground_state(), compute_propagators(), evaluate(), process()
-
-        # generate shots style readout with no SPAM
-        # TODO a sophisticated readout/measurement routine
-
-        # TODO generate state labels using get_labels()
+        pops = exp.evaluate([instructions_list])
+        pop1s, _ = exp.process(pops)
 
-        # TODO create results dict and remove empty states
-        counts = {}  # type: ignore
+        # TODO generate shots style readout ref Perfect Simulator
+        # TODO a sophisticated readout/measurement routine (w/ SPAM)
+        # C3 stores labels in exp.pmap.model.state_labels
+        counts = dict(zip(self.get_labels(), pop1s[0].numpy().tolist()))
 
         # flipping state labels to match qiskit style qubit indexing convention
         # default is to flip labels to qiskit style, use disable_flip_labels()
-        if self._flip_labels:
-            counts = flip_labels(counts)
+        # if self._flip_labels:
+        #     counts = flip_labels(counts)
 
         end = time.time()