Source code for pyscf.pbc.cc.eom_kccsd_rhf_ea

#!/usr/bin/env python
# Copyright 2014-2019 The PySCF Developers. All Rights Reserved.
#
# 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.
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# Authors: Artem Pulkin, pyscf authors

from pyscf.pbc.lib.kpts_helper import VectorSplitter, VectorComposer
from pyscf.pbc.mp.kmp2 import padding_k_idx
from pyscf.pbc.cc import kccsd_rhf

import numpy as np


[docs] def iter_12(cc_or_eom, k): """Iterates over EA index slices.""" if isinstance(cc_or_eom, kccsd_rhf.RCCSD): cc = cc_or_eom else: cc = cc_or_eom._cc o, v = padding_k_idx(cc, kind="split") kconserv = cc.khelper.kconserv yield (v[k],) for ki in range(cc.nkpts): for ka in range(cc.nkpts): kb = kconserv[k, ka, ki] yield (ki,), (ka,), o[ki], v[ka], v[kb]
[docs] def amplitudes_to_vector(cc_or_eom, t1, t2, kshift=0, kconserv=None): """EA amplitudes to vector.""" itr = iter_12(cc_or_eom, kshift) t1, t2 = np.asarray(t1), np.asarray(t2) vc = VectorComposer(t1.dtype) vc.put(t1[np.ix_(*next(itr))]) for slc in itr: vc.put(t2[np.ix_(*slc)]) return vc.flush()
[docs] def vector_to_amplitudes(cc_or_eom, vec, kshift=0): """EA vector to apmplitudes.""" expected_vs = vector_size(cc_or_eom, kshift) if expected_vs != len(vec): raise ValueError("The size of the vector passed {:d} should be exactly {:d}".format(len(vec), expected_vs)) itr = iter_12(cc_or_eom, kshift) nocc = cc_or_eom.nocc nmo = cc_or_eom.nmo nkpts = cc_or_eom.nkpts nvirt = nmo - nocc vs = VectorSplitter(vec) r1 = vs.get(nvirt, slc=next(itr)) r2 = np.zeros((nkpts, nkpts, nocc, nvirt, nvirt), vec.dtype) for slc in itr: vs.get(r2, slc=slc) return r1, r2
[docs] def vector_size(cc_or_eom, kshift=0): """The total number of elements in EA vector.""" size = 0 for slc in iter_12(cc_or_eom, kshift): size += np.prod(tuple(len(i) for i in slc)) return size