✨ switch to mqt-core Python package

Signed-off-by: burgholzer <burgholzer@me.com>

.pre-commit-config.yaml

@@ -98,6 +98,7 @@ repos:
         additional_dependencies:
           - numpy
           - pytest
+          - mqt.core~=2.2.2
 
   # Check for spelling
   - repo: https://github.com/codespell-project/codespell

cmake/ExternalDependencies.cmake

@@ -4,6 +4,18 @@ include(FetchContent)
 set(FETCH_PACKAGES "")
 
 if(BUILD_MQT_DDSIM_BINDINGS)
+  # Manually detect the installed mqt-core package.
+  execute_process(
+    COMMAND "${Python_EXECUTABLE}" -m mqt.core --cmake_dir
+    OUTPUT_STRIP_TRAILING_WHITESPACE
+    OUTPUT_VARIABLE mqt-core_DIR
+    ERROR_QUIET)
+
+  # Add the detected directory to the CMake prefix path.
+  if(mqt-core_DIR)
+    list(APPEND CMAKE_PREFIX_PATH "${mqt-core_DIR}")
+    message(STATUS "Found mqt-core package: ${mqt-core_DIR}")
+  endif()
   if(NOT SKBUILD)
     # Manually detect the installed pybind11 package.
     execute_process(
@@ -19,12 +31,6 @@ if(BUILD_MQT_DDSIM_BINDINGS)
   find_package(pybind11 CONFIG REQUIRED)
 endif()
 
-set(FETCHCONTENT_SOURCE_DIR_MQT-CORE
-    ${PROJECT_SOURCE_DIR}/extern/mqt-core
-    CACHE
-      PATH
-      "Path to the source directory of the mqt-core library. This variable is used by FetchContent to download the library if it is not already available."
-)
 set(MQT_CORE_VERSION
     2.2.2
     CACHE STRING "MQT Core version")

noxfile.py

@@ -17,6 +17,7 @@
 PYTHON_ALL_VERSIONS = ["3.8", "3.9", "3.10", "3.11", "3.12"]
 
 BUILD_REQUIREMENTS = [
+    "mqt.core~=2.2.2",
     "scikit-build-core[pyproject]>=0.6.1",
     "setuptools_scm>=7",
     "pybind11>=2.11",

pyproject.toml

@@ -1,5 +1,10 @@
 [build-system]
-requires = ["scikit-build-core>=0.6.1", "setuptools-scm>=7", "pybind11>=2.11"]
+requires = [
+    "scikit-build-core>=0.6.1",
+    "setuptools-scm>=7",
+    "pybind11>=2.11",
+    "mqt.core~=2.2.2",
+]
 build-backend = "scikit_build_core.build"
 
 [project]
@@ -34,7 +39,7 @@ classifiers = [
 ]
 requires-python = ">=3.8"
 dependencies = [
-    "qiskit[qasm3-import]>=0.45.0"
+    "mqt.core[qiskit]~=2.2.2",
 ]
 dynamic = ["version"]
 
@@ -103,14 +108,6 @@ sdist.exclude = [
     "**/plots",
     "**/test",
     "**/tests",
-    "extern/mqt-core/extern/json/include",
-    "extern/mqt-core/extern/googletest",
-    "extern/mqt-core/extern/boost/config/checks",
-    "extern/mqt-core/extern/boost/config/tools",
-    "extern/mqt-core/extern/boost/multiprecision/config",
-    "extern/mqt-core/extern/boost/multiprecision/example",
-    "extern/mqt-core/extern/boost/multiprecision/performance",
-    "extern/mqt-core/extern/boost/multiprecision/tools"
 ]
 
 [tool.scikit-build.cmake.define]

src/mqt/ddsim/hybridqasmsimulator.py

@@ -14,6 +14,8 @@
 from qiskit.transpiler import Target
 from qiskit.utils.multiprocessing import local_hardware_info
 
+from mqt.core.io import load
+
 from .header import DDSIMHeader
 from .pyddsim import HybridCircuitSimulator, HybridMode
 from .qasmsimulator import QasmSimulatorBackend
@@ -74,7 +76,8 @@ def _run_experiment(self, qc: QuantumCircuit, **options: Any) -> ExperimentResul
             msg = f"Simulation mode{mode} not supported by hybrid simulator. Available modes are 'amplitude' and 'dd'."
             raise QiskitError(msg)
 
-        sim = HybridCircuitSimulator(qc, seed=seed, mode=hybrid_mode, nthreads=nthreads)
+        circuit = load(qc)
+        sim = HybridCircuitSimulator(circuit, seed=seed, mode=hybrid_mode, nthreads=nthreads)
 
         shots = options.get("shots", 1024)
         if self._SHOW_STATE_VECTOR and shots > 0:

src/mqt/ddsim/pathqasmsimulator.py

@@ -7,13 +7,17 @@
 from typing import TYPE_CHECKING, Any
 
 if TYPE_CHECKING:
+    from qiskit import QuantumCircuit
     from quimb.tensor import Tensor, TensorNetwork
 
-from qiskit import QuantumCircuit
+    from mqt.core import QuantumComputation
+
 from qiskit.providers import Options
 from qiskit.result.models import ExperimentResult, ExperimentResultData
 from qiskit.transpiler import Target
 
+from mqt.core.io import load
+
 from .header import DDSIMHeader
 from .pyddsim import PathCircuitSimulator, PathSimulatorConfiguration, PathSimulatorMode
 from .qasmsimulator import QasmSimulatorBackend
@@ -38,18 +42,14 @@ def read_tensor_network_file(filename: str) -> list[Tensor]:
     return tensors
 
 
-def create_tensor_network(qc: QuantumCircuit) -> TensorNetwork:
+def create_tensor_network(qc: QuantumComputation) -> TensorNetwork:
     import quimb.tensor as qtn
     import sparse
 
     from mqt.ddsim import dump_tensor_network
 
-    if isinstance(qc, QuantumCircuit):
-        filename = qc.name + "_" + str(qc.num_qubits) + ".tensor"
-        nqubits = qc.num_qubits
-    else:
-        filename = "tensor.tensor"
-        nqubits = qc.header.n_qubits
+    filename = qc.name + "_" + str(qc.num_qubits) + ".tensor"
+    nqubits = qc.num_qubits
 
     dump_tensor_network(qc, filename)
     tensors = read_tensor_network_file(filename)
@@ -78,7 +78,7 @@ def create_tensor_network(qc: QuantumCircuit) -> TensorNetwork:
 
 
 def get_simulation_path(
-    qc: QuantumCircuit,
+    qc: QuantumComputation,
     max_time: int = 60,
     max_repeats: int = 1024,
     parallel_runs: int = 1,
@@ -101,7 +101,7 @@ def get_simulation_path(
     path = linear_to_ssa(info.path)
 
     if dump_path:
-        filename = qc.name + "_" + str(qc.num_qubits) + ".path" if isinstance(qc, QuantumCircuit) else "simulation.path"
+        filename = qc.name + "_" + str(qc.num_qubits) + ".path"
         with pathlib.Path(filename).open("w") as file:
             file.write(str(path))
 
@@ -181,7 +181,8 @@ def _run_experiment(self, qc: QuantumCircuit, **options: Any) -> ExperimentResul
         if seed is not None:
             pathsim_configuration.seed = seed
 
-        sim = PathCircuitSimulator(qc, config=pathsim_configuration)
+        circuit = load(qc)
+        sim = PathCircuitSimulator(circuit, config=pathsim_configuration)
 
         # determine the contraction path using cotengra in case this is requested
         if pathsim_configuration.mode == PathSimulatorMode.cotengra:
@@ -190,7 +191,11 @@ def _run_experiment(self, qc: QuantumCircuit, **options: Any) -> ExperimentResul
             dump_path = options.get("cotengra_dump_path", False)
             plot_ring = options.get("cotengra_plot_ring", False)
             path = get_simulation_path(
-                qc, max_time=max_time, max_repeats=max_repeats, dump_path=dump_path, plot_ring=plot_ring
+                circuit,
+                max_time=max_time,
+                max_repeats=max_repeats,
+                dump_path=dump_path,
+                plot_ring=plot_ring,
             )
             sim.set_simulation_path(path, False)
 

src/mqt/ddsim/primitives/estimator.py

@@ -16,6 +16,7 @@
 )
 from qiskit.quantum_info import Pauli, PauliList, SparsePauliOp
 
+from mqt.core.io import load
 from mqt.ddsim.pyddsim import CircuitSimulator
 from mqt.ddsim.qasmsimulator import QasmSimulatorBackend
 
@@ -235,15 +236,16 @@ def _run_experiment(
         approximation_strategy = options.get("approximation_strategy", "fidelity")
         seed = options.get("seed_simulator", -1)
 
+        qc = load(circ)
         sim = CircuitSimulator(
-            circ,
+            qc,
             approximation_step_fidelity=approximation_step_fidelity,
             approximation_steps=approximation_steps,
             approximation_strategy=approximation_strategy,
             seed=seed,
         )
 
-        return [sim.expectation_value(observable=obs) for obs in obs_circ_list]
+        return [sim.expectation_value(observable=load(obs)) for obs in obs_circ_list]
 
     @staticmethod
     def _postprocessing(result_list: list[float], accum: list[int], metadata: list[dict]) -> EstimatorResult:

src/mqt/ddsim/qasmsimulator.py

@@ -15,6 +15,8 @@
 from qiskit.transpiler import Target
 from qiskit.utils.multiprocessing import local_hardware_info
 
+from mqt.core.io import load
+
 from . import __version__
 from .header import DDSIMHeader
 from .job import DDSIMJob
@@ -161,8 +163,9 @@ def _run_experiment(self, qc: QuantumCircuit, **options: dict[str, Any]) -> Expe
         seed = options.get("seed_simulator", -1)
         shots = options.get("shots", 1024)
 
+        circuit = load(qc)
         sim = CircuitSimulator(
-            qc,
+            circuit,
             approximation_step_fidelity=approximation_step_fidelity,
             approximation_steps=approximation_steps,
             approximation_strategy=approximation_strategy,

src/mqt/ddsim/unitarysimulator.py

@@ -12,6 +12,8 @@
 from qiskit.result.models import ExperimentResult, ExperimentResultData
 from qiskit.transpiler import Target
 
+from mqt.core.io import load
+
 from .header import DDSIMHeader
 from .pyddsim import ConstructionMode, UnitarySimulator, get_matrix
 from .qasmsimulator import QasmSimulatorBackend
@@ -66,7 +68,8 @@ def _run_experiment(cls, qc: QuantumCircuit, **options: Any) -> ExperimentResult
             )
             raise QiskitError(msg)
 
-        sim = UnitarySimulator(qc, seed=seed, mode=construction_mode)
+        circuit = load(qc)
+        sim = UnitarySimulator(circuit, seed=seed, mode=construction_mode)
         sim.construct()
         # Extract resulting matrix from final DD and write data
         unitary: npt.NDArray[np.complex128] = np.zeros((2**qc.num_qubits, 2**qc.num_qubits), dtype=np.complex128)

src/python/bindings.cpp

@@ -7,7 +7,6 @@
 #include "HybridSchrodingerFeynmanSimulator.hpp"
 #include "PathSimulator.hpp"
 #include "UnitarySimulator.hpp"
-#include "python/qiskit/QuantumCircuit.hpp"
 
 #include <memory>
 #include <pybind11/numpy.h>
@@ -17,33 +16,14 @@
 namespace py = pybind11;
 using namespace pybind11::literals;
 
-static qc::QuantumComputation importCircuit(const py::object& circ) {
-    const py::object quantumCircuit =
-            py::module::import("qiskit").attr("QuantumCircuit");
-
-    auto qc = qc::QuantumComputation();
-
-    if (py::isinstance<py::str>(circ)) {
-        const auto file = circ.cast<std::string>();
-        qc.import(file);
-    } else if (py::isinstance(circ, quantumCircuit)) {
-        qc::qiskit::QuantumCircuit::import(qc, circ);
-    } else {
-        throw std::runtime_error(
-                "PyObject is neither py::str nor QuantumCircuit");
-    }
-
-    return qc;
-}
-
 template<class Simulator, typename... Args>
-std::unique_ptr<Simulator> constructSimulator(const py::object&  circ,
-                                              const double       stepFidelity,
-                                              const unsigned int stepNumber,
-                                              const std::string& approximationStrategy,
-                                              const std::int64_t seed,
+std::unique_ptr<Simulator> constructSimulator(const qc::QuantumComputation& circ,
+                                              const double                  stepFidelity,
+                                              const unsigned int            stepNumber,
+                                              const std::string&            approximationStrategy,
+                                              const std::int64_t            seed,
                                               Args&&... args) {
-    auto       qc     = std::make_unique<qc::QuantumComputation>(importCircuit(circ));
+    auto       qc     = std::make_unique<qc::QuantumComputation>(circ);
     const auto approx = ApproximationInfo{stepFidelity, stepNumber, ApproximationInfo::fromString(approximationStrategy)};
     if constexpr (std::is_same_v<Simulator, PathSimulator<>>) {
         return std::make_unique<Simulator>(std::move(qc),
@@ -62,7 +42,7 @@ std::unique_ptr<Simulator> constructSimulator(const py::object&  circ,
 }
 
 template<class Simulator, typename... Args>
-std::unique_ptr<Simulator> constructSimulatorWithoutSeed(const py::object& circ, Args&&... args) {
+std::unique_ptr<Simulator> constructSimulatorWithoutSeed(const qc::QuantumComputation& circ, Args&&... args) {
     return constructSimulator<Simulator>(circ, 1., 1, "fidelity", -1, std::forward<Args>(args)...);
 }
 
@@ -114,26 +94,9 @@ void getNumPyMatrix(UnitarySimulator<Config>& sim, py::array_t<std::complex<dd::
     getNumPyMatrixRec(e, std::complex<dd::fp>{1.0, 0.0}, 0, 0, dim, dataPtr);
 }
 
-void dumpTensorNetwork(const py::object& circ, const std::string& filename) {
-    const py::object quantumCircuit = py::module::import("qiskit").attr("QuantumCircuit");
-
-    std::unique_ptr<qc::QuantumComputation> qc = std::make_unique<qc::QuantumComputation>();
-
-    if (py::isinstance<py::str>(circ)) {
-        auto&& file1 = circ.cast<std::string>();
-        qc->import(file1);
-    } else if (py::isinstance(circ, quantumCircuit)) {
-        qc::qiskit::QuantumCircuit::import(*qc, circ);
-    } else {
-        throw std::runtime_error("PyObject is neither py::str nor QuantumCircuit");
-    }
+void dumpTensorNetwork(qc::QuantumComputation& circ, const std::string& filename) {
     std::ofstream ofs(filename);
-    qc->dump(ofs, qc::Format::Tensor);
-}
-
-dd::fp expectationValue(CircuitSimulator<>& sim, const py::object& observable) {
-    const auto observableCircuit = importCircuit(observable);
-    return sim.expectationValue(observableCircuit);
+    circ.dump(ofs, qc::Format::Tensor);
 }
 
 template<class Sim>
@@ -171,7 +134,7 @@ PYBIND11_MODULE(pyddsim, m) {
                          "approximation_steps"_a         = 1,
                          "approximation_strategy"_a      = "fidelity",
                          "seed"_a                        = -1)
-            .def("expectation_value", &expectationValue, "observable"_a);
+            .def("expectation_value", &CircuitSimulator<>::expectationValue, "observable"_a);
 
     // Hybrid Schrödinger-Feynman Simulator
     py::enum_<HybridSchrodingerFeynmanSimulator<>::Mode>(m, "HybridMode")

test/python/constraints.txt

@@ -2,4 +2,5 @@ scikit-build-core==0.6.1
 setuptools-scm==7.0.0
 pybind11==2.11.0
 pytest==7.0.0
+mqt.core==2.2.2
 qiskit==0.45.0

test/python/hybridsimulator/test_hybrid_standalone_simulator.py

@@ -2,19 +2,18 @@
 
 import unittest
 
-from qiskit import QuantumCircuit, QuantumRegister
-
 from mqt import ddsim
+from mqt.core import QuantumComputation
 
 
 class MQTStandaloneHybridSimulatorTest(unittest.TestCase):
     def setUp(self) -> None:
-        q = QuantumRegister(4)
-        circ = QuantumCircuit(q)
-        circ.h(q)
+        circ = QuantumComputation(4)
+        for i in range(4):
+            circ.h(i)
         circ.cz(3, 1)
         circ.cz(2, 0)
-        circ.measure_all(inplace=True)
+        circ.measure_all()
         self.circuit = circ
         self.non_zeros_in_matrix = 16