# Copyright 2019 1QBit
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import abc
[docs]class ElectronicStructureSolver(abc.ABC):
"""Sets interface for objects that perform energy estimation of a molecule.
Specifics vary between concrete implementations, but common to all of them
is that after `simulate` is called, the right internal state is set for the
class so that `get_rdm` can return the reduced density matrix for the last
run simulation.
"""
def __init__(self):
pass
[docs] @abc.abstractmethod
def simulate(self, molecule, mean_field=None):
"""Performs the simulation for a molecule.
The mean field is calculated automatically if not passed in by the
calling code.
Args:
molecule (pyscf.gto.Mole): The molecule on which to perform the
simluation.
mean_field (pyscf.scf.RHF): The mean filed of the molecule. Computed
automatically if `None` is passed in.
"""
pass
[docs] @abc.abstractmethod
def get_rdm(self):
"""Returns the RDM for the previous simulation.
In a concrete implementation, the `simulate` function would set the
necessary internal state for the class so that this function can return
the reduced density matrix.
Returns:
(numpy.array, numpy.array): The one- and two-particle RDMs (float64).
Raises:
RuntimeError: If no simulation has been run.
"""
pass