feat: Example of python script

compiling.py

@@ -0,0 +1,129 @@
+import argparse
+import json
+import logging
+import pathlib
+
+import numpy as np
+import qibo
+from qibo import hamiltonians
+from qibo.backends import construct_backend
+
+from boostvqe.ansatze import VQE, build_circuit
+from boostvqe.models.dbi.double_bracket_evolution_oracles import (
+    MagneticFieldEvolutionOracle,
+    VQERotatedEvolutionOracle,
+    XXZ_EvolutionOracle,
+)
+from boostvqe.models.dbi.group_commutator_iteration_transpiler import (
+    DoubleBracketRotationType,
+    VQEBoostingGroupCommutatorIteration,
+)
+from boostvqe.utils import (
+    OPTIMIZATION_FILE,
+    PARAMS_FILE,
+    build_circuit,
+    get_eo_d_initializations,
+    print_vqe_comparison_report,
+    select_recursion_step_gd_circuit,
+)
+
+logging.basicConfig(level=logging.INFO)
+
+
+def main(args):
+    """VQE training."""
+    path = args.path
+
+    config = json.loads((path / OPTIMIZATION_FILE).read_text())
+
+    # TODO: improve loading of params
+    try:
+        params = np.load(path / f"parameters/params_ite{args.epoch}.npy")
+    except FileNotFoundError:
+        params = np.array(
+            np.load(path / PARAMS_FILE, allow_pickle=True).tolist()[0][args.epoch]
+        )
+    nqubits = config["nqubits"]
+    nlayers = config["nlayers"]
+    vqe_backend = construct_backend(backend=config["backend"])
+    # TODO: remove delta hardcoded
+    hamiltonian = getattr(hamiltonians, config["hamiltonian"])(
+        nqubits=nqubits, delta=0.5, backend=vqe_backend
+    )
+    vqe = VQE(
+        build_circuit(
+            nqubits=nqubits,
+            nlayers=nlayers,
+        ),
+        hamiltonian=hamiltonian,
+    )
+    vqe.circuit.set_parameters(params)
+
+    base_oracle = XXZ_EvolutionOracle(
+        nqubits=nqubits, steps=args.steps, order=args.order
+    )
+    oracle = VQERotatedEvolutionOracle(base_oracle, vqe)
+
+    gci = VQEBoostingGroupCommutatorIteration(
+        input_hamiltonian_evolution_oracle=oracle,
+        mode_double_bracket_rotation=args.db_rotation,
+    )
+    # TODO: remove hardcoded magnetic field
+    eo_d = MagneticFieldEvolutionOracle([4 - np.sin(x / 3) for x in range(nqubits)])
+
+    gci.eo_d = eo_d
+    print(
+        f"The gci mode is {gci.mode_double_bracket_rotation} rotation with {gci.eo_d.name} as the oracle.\n"
+    )
+    print_vqe_comparison_report(gci)
+    boosting_callback_data = {}
+    for gci_step_nmb in range(args.steps):
+        mode_dbr, minimizer_s, minimal_loss, eo_d = select_recursion_step_gd_circuit(
+            gci,
+            mode_dbr_list=[args.db_rotation],
+            step_grid=np.linspace(1e-5, 2e-2, 30),
+            lr_range=(1e-3, 1),
+            nmb_gd_epochs=args.gd_steps,
+            threshold=1e-4,
+            max_eval_gd=30,
+            save_path=args.path.name,
+        )
+
+        gci.mode_double_bracket_rotation = mode_dbr
+        gci.eo_d = eo_d
+        gci(minimizer_s)
+        print(f"Executing gci step {gci_step_nmb+1}:\n")
+        print(
+            f"The selected data is {gci.mode_double_bracket_rotation} rotation with {gci.eo_d.name} for the duration s = {minimizer_s}."
+        )
+        print("--- the report after execution:\n")
+        print_vqe_comparison_report(gci)
+        print("==== the execution report ends here")
+        boosting_callback_data[gci_step_nmb] = gci.get_vqe_boosting_data()
+    # TODO: store metadata
+    # (args.path / "boosting_data.json").write_text(json.dumps(boosting_callback_data))
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description="Boosting VQE with DBI.")
+    parser.add_argument("--backend", default="qibojit", type=str, help="Qibo backend")
+    parser.add_argument("--path", type=pathlib.Path, help="Output folder")
+    parser.add_argument(
+        "--epoch", default=-1, type=int, help="VQE epoch where DBI will be applied."
+    )
+    parser.add_argument("--steps", default=2, type=int, help="DBI steps")
+    parser.add_argument(
+        "--gd_steps", default=1, type=int, help="Gradient descent steps"
+    )
+    parser.add_argument("--order", default=2, type=int, help="Suzuki-Trotter order")
+    parser.add_argument(
+        "--db_rotation",
+        default=DoubleBracketRotationType.group_commutator_reduced_twice,
+        type=DoubleBracketRotationType,
+        help="DB rotation type.",
+    )
+    parser.add_argument(
+        "--eo_d_name", default="B Field", type=str, help="D initialization"
+    )
+    args = parser.parse_args()
+    main(args)