# C贸digo fuente para qiskit.algorithms.time_evolvers.classical_methods.scipy_real_evolver

# This code is part of Qiskit.
#
#
# obtain a copy of this license in the LICENSE.txt file in the root directory
#
# Any modifications or derivative works of this code must retain this
# copyright notice, and modified files need to carry a notice indicating
# that they have been altered from the originals.

"""Classical Quantum Real Time Evolution."""
from .evolve import _evolve
from ..time_evolution_problem import TimeEvolutionProblem
from ..time_evolution_result import TimeEvolutionResult
from ..real_time_evolver import RealTimeEvolver

[documentos]class SciPyRealEvolver(RealTimeEvolver):
r"""Classical Evolver for real time evolution.

Evolves an initial state :math:|\Psi\rangle for a time :math:t
under a Hamiltonian :math:H, as provided in the evolution_problem.
Note that the precision of the evolver does not depend on the number of
timesteps taken.
"""

def __init__(self, num_timesteps: int):
"""
Args:
num_timesteps: The number of timesteps in the simulation.
Raises:
ValueError: If steps is not a positive integer.
"""
self.num_timesteps = num_timesteps

[documentos]    def evolve(self, evolution_problem: TimeEvolutionProblem) -> TimeEvolutionResult:
r"""Perform real time evolution :math:\exp(-i t H)|\Psi\rangle.

Evolves an initial state :math:|\Psi\rangle for a time :math:t
under a Hamiltonian  :math:H, as provided in the evolution_problem.

Args:
evolution_problem: The definition of the evolution problem.

Returns:
Evolution result which includes an evolved quantum state.
"""
return _evolve(evolution_problem, self.num_timesteps, real_time=True)