I want to record the time that a VQE solver takes to find the ground state. At the moment I am using:
%matplotlib inline # Importing standard Qiskit libraries and configuring account from qiskit import QuantumCircuit, execute, Aer, IBMQ from qiskit.compiler import transpile, assemble from qiskit.tools.jupyter import * from qiskit.visualization import * import numpy as np import matplotlib.pyplot as plt import time # Loading your IBM Q account(s) and assigning backend IBMQ.load_account() provider = IBMQ.get_provider('ibm-q') qcomp = provider.get_backend('ibmq_valencia') #Imports for algorithm from qiskit.chemistry.drivers import PySCFDriver, UnitsType, Molecule from qiskit.chemistry.transformations import FermionicTransformation, FermionicQubitMappingType from qiskit.aqua.algorithms import NumPyMinimumEigensolver from qiskit import BasicAer from qiskit.aqua import QuantumInstance from qiskit.chemistry.algorithms.ground_state_solvers.minimum_eigensolver_factories import VQEUCCSDFactory from qiskit.chemistry.algorithms.ground_state_solvers import GroundStateEigensolver #Define molecule molecule = Molecule(geometry=[['H', [0., 0., 0.]], ['H', [0., 0., 0.735]]], charge=0, multiplicity=1) driver = PySCFDriver(molecule = molecule, unit=UnitsType.ANGSTROM, basis='sto3g') #Map fermionic hamiltonian to qubit hamiltonian transformation = FermionicTransformation(qubit_mapping=FermionicQubitMappingType.PARITY, two_qubit_reduction=True, freeze_core=True) #Initialize the VQE solver vqe_solver = VQEUCCSDFactory(QuantumInstance(backend = qcomp)) #Ground state algorithm calculation_VQE = GroundStateEigensolver(transformation, vqe_solver) #Calculate results start = time.time() VQE_result = calculation_VQE.solve(driver) end = time.time() time_difference = (end - start) print(VQE_result.total_energies) print(time_difference)
However, after running this a few times on different IBM quantum machines, I am quite sure that the times I am recording are including the time spent waiting in queue to run the computations (but not completely certain on this). Is there any way to record the time taken by the VQE to compute the ground state energy without including queue time.