#!/usr/bin/env python
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from pyscf.lib import logger, current_memory, tag_array
from pyscf.dft.gen_grid import BLKSIZE
from pyscf.mcpdft.otpd import get_ontop_pair_density
from pyscf.mcpdft.pdft_eff import _ERIS
import numpy as np
import gc
# MRH 05/18/2020: An annoying convention in pyscf.dft.numint that I have to
# comply with is that the AO grid-value arrays and all their derivatives are in
# NEITHER column-major NOR row-major order; they all have ndim = 3 and strides
# of (8*ngrids*nao, 8, 8*ngrids). Here, for my ndim > 3 objects, I choose to
# generalize this so that a cyclic transpose to the left,
# ao.transpose (1,2,3,...,0), places the array in column-major (FORTRAN-style)
# order. I have to comply with this awkward convention in order to take full
# advantage of the code in pyscf.dft.numint and libdft.so. The ngrids
# dimension, which is by far the largest, almost always benefits from having
# the smallest stride.
# MRH 05/19/2020: Actually, I really should just turn the deriv component part
# of all of these arrays into lists and keep everything in col-major order
# otherwise, because ndarrays have to have regular strides, but lists can just
# be references and less copying is involved. The copying is more expensive and
# less transparently parallel-scalable than the actual math! (The
# parallel-scaling part of that is stupid but it is what it is.)
[docs]
def kernel(ot, dm1s, cascm2, mo_coeff, ncore, ncas,
max_memory=2000, hermi=1, paaa_only=False, aaaa_only=False,
jk_pc=False):
'''Get the 1- and 2-body effective potential from MC-PDFT.
Args:
ot : an instance of otfnal class
dm1s : ndarray of shape (2, nao, nao)
containing spin-separated one-body density matrices
cascm2 : ndarray of shape (ncas, ncas, ncas, ncas)
containing spin-summed two-body cumulant density matrix in
an active space
mo_coeff : ndarray of shape (nao, nmo)
containing molecular orbital coefficients
ncore : integer
number of inactive orbitals
ncas : integer
number of active orbitals
Kwargs:
max_memory : int or float
maximum cache size in MB
default is 2000
hermi : int
1 if 1rdms are assumed hermitian, 0 otherwise
paaa_only : logical
If true, only compute the paaa range of papa and ppaa
(all other elements set to zero)
aaaa_only : logical
If true, only compute the aaaa range of papa and ppaa
(all other elements set to zero; overrides paaa_only)
jk_pc : logical
If true, compute the ppii=pipi elements of veff2
(otherwise, these are set to zero)
Returns:
veff1 : ndarray of shape (nao, nao)
1-body effective potential
veff2 : object of class pdft_eff._ERIS
2-body effective potential and related quantities
'''
nocc = ncore + ncas
ni, xctype, dens_deriv = ot._numint, ot.xctype, ot.dens_deriv
nao = mo_coeff.shape[0]
mo_core = mo_coeff[:, :ncore]
mo_cas = mo_coeff[:, ncore:nocc]
shls_slice = (0, ot.mol.nbas)
ao_loc = ot.mol.ao_loc_nr()
omega, alpha, hyb = ot._numint.rsh_and_hybrid_coeff(ot.otxc)
hyb_x, hyb_c = hyb
if abs(omega) > 1e-11:
raise NotImplementedError("range-separated on-top functionals")
if abs(hyb_x - hyb_c) > 1e-11:
raise NotImplementedError(
"effective potential for hybrid functionals with different exchange, correlations components")
E_ot = 0.0
veff1 = np.zeros((nao, nao), dtype=dm1s.dtype)
veff2 = _ERIS(ot.mol, mo_coeff, ncore, ncas, paaa_only=paaa_only,
aaaa_only=aaaa_only, jk_pc=jk_pc, verbose=ot.verbose,
stdout=ot.stdout)
t0 = (logger.process_clock(), logger.perf_counter())
# Density matrices
dm_core = mo_core @ mo_core.T
dm_cas = dm1s - dm_core[None, :, :]
dm_core *= 2
# Propagate speedup tags
if hasattr(dm1s, 'mo_coeff') and hasattr(dm1s, 'mo_occ'):
dm_core = tag_array(dm_core, mo_coeff=dm1s.mo_coeff[0, :, :ncore],
mo_occ=dm1s.mo_occ[:, :ncore].sum(0))
dm_cas = tag_array(dm_cas, mo_coeff=dm1s.mo_coeff[:, :, ncore:nocc],
mo_occ=dm1s.mo_occ[:, ncore:nocc])
# rho generators
make_rho_c = ni._gen_rho_evaluator(ot.mol, dm_core, hermi=hermi, with_lapl=False)[0]
make_rho_a = ni._gen_rho_evaluator(ot.mol, dm_cas, hermi=hermi, with_lapl=False)[0]
make_rho = ni._gen_rho_evaluator(ot.mol, dm1s, hermi=hermi, with_lapl=False)[0]
# memory block size
gc.collect()
remaining_floats = (max_memory - current_memory()[0]) * 1e6 / 8
nderiv_rho = (1, 4, 5)[dens_deriv]
nderiv_Pi = (1, 4)[ot.Pi_deriv]
nderiv_ao = (1,4,10)[dens_deriv]
ncols = 4 + nderiv_rho * nao # ao, weight, coords
ncols += nderiv_rho * 4 + nderiv_Pi # rho, rho_a, rho_c, Pi
ncols += 1 + nderiv_rho + nderiv_Pi # eot, vot
# Asynchronous part
nveff1 = nderiv_ao * (nao + 1) # footprint of get_veff_1body
nveff2 = veff2._accumulate_ftpt() * nderiv_Pi
ncols += np.amax([nveff1, nveff2]) # asynchronous fns
pdft_blksize = int(remaining_floats / (ncols * BLKSIZE)) * BLKSIZE
if ot.grids.coords is None:
ot.grids.build(with_non0tab=True)
ngrids = ot.grids.coords.shape[0]
ngrids_blk = int(ngrids / BLKSIZE) * BLKSIZE
pdft_blksize = max(BLKSIZE, min(pdft_blksize, ngrids_blk, BLKSIZE * 1200))
logger.debug(ot, ('{} MB used of {} available; block size of {} chosen'
'for grid with {} points').format(current_memory()[0], max_memory,
pdft_blksize, ngrids))
# The actual loop
for ao, mask, weight, coords in ni.block_loop(ot.mol, ot.grids, nao,
dens_deriv, max_memory, blksize=pdft_blksize):
rho = np.asarray([make_rho(i, ao, mask, xctype) for i in range(2)])
rho_a = sum([make_rho_a(i, ao, mask, xctype) for i in range(2)])
rho_c = make_rho_c(0, ao, mask, xctype)
t0 = logger.timer(ot, 'untransformed densities (core and total)', *t0)
Pi = get_ontop_pair_density(ot, rho, ao, cascm2, mo_cas,
deriv=ot.Pi_deriv, non0tab=mask)
t0 = logger.timer(ot, 'on-top pair density calculation', *t0)
eot, vot = ot.eval_ot(rho, Pi, weights=weight)[:2]
E_ot += eot.dot(weight)
vrho, vPi = vot
t0 = logger.timer(ot, 'effective potential kernel calculation', *t0)
if ao.ndim == 2: ao = ao[None, :, :]
# TODO: consistent format req's ao LDA case
veff1 += ot.get_eff_1body(ao, weight, kern=vrho, non0tab=mask,
shls_slice=shls_slice, ao_loc=ao_loc, hermi=1)
t0 = logger.timer(ot, '1-body effective potential calculation', *t0)
veff2._accumulate(ot, ao, weight, rho_c, rho_a, vPi, mask,
shls_slice, ao_loc)
t0 = logger.timer(ot, '2-body effective potential calculation', *t0)
veff2._finalize()
t0 = logger.timer(ot, 'Finalizing 2-body effective potential calculation',
*t0)
return E_ot, veff1, veff2
[docs]
def lazy_kernel(ot, dm1s, cascm2, mo_cas, max_memory=2000, hermi=1,
veff2_mo=None):
'''Get the 1- and 2-body effective potential from MC-PDFT.
Eventually I'll be able to specify mo slices for the 2-body part
Args:
ot : an instance of otfnal class
dm1s : ndarray of shape (2, nao, nao)
containing spin-separated one-body density matrices
cascm2 : ndarray of shape (ncas, ncas, ncas, ncas)
containing spin-summed two-body cumulant density matrix
in an active space
mo_cas : ndarray of shape (nao, ncas)
containing molecular orbital coefficients for
active-space orbitals
Kwargs:
max_memory : int or float
maximum cache size in MB
default is 2000
hermi : int
1 if 1rdms are assumed hermitian, 0 otherwise
Returns : float
The MC-PDFT on-top exchange-correlation energy
'''
if veff2_mo is not None:
raise NotImplementedError('Molecular orbital slices for 2-body part')
ni, xctype = ot._numint, ot.xctype
dens_deriv = ot.dens_deriv
Pi_deriv = ot.Pi_deriv
nao = mo_cas.shape[0]
veff1 = np.zeros_like(dm1s[0])
veff2 = np.zeros((nao, nao, nao, nao), dtype=veff1.dtype)
t0 = (logger.process_clock(), logger.perf_counter())
make_rho = tuple(ni._gen_rho_evaluator(ot.mol, dm1s[i, :, :], hermi=hermi, with_lapl=False)
for i in range(2))
for ao, mask, weight, coords in ni.block_loop(ot.mol, ot.grids, nao,
dens_deriv, max_memory):
rho = np.asarray([m[0](0, ao, mask, xctype) for m in make_rho])
t0 = logger.timer(ot, 'untransformed density', *t0)
Pi = get_ontop_pair_density(ot, rho, ao, cascm2, mo_cas,
deriv=Pi_deriv, non0tab=mask)
t0 = logger.timer(ot, 'on-top pair density calculation', *t0)
_, vot = ot.eval_ot(rho, Pi, weights=weight)[:2]
vrho, vPi = vot
t0 = logger.timer(ot, "effective potential kernel calculation", *t0)
if ao.ndim == 2:
ao = ao[None, :, :]
# TODO: consistent format req's ao LDA case
veff1 += ot.get_eff_1body(ao, weight, kern=vrho, non0tab=mask)
t0 = logger.timer(ot, '1-body effective potential calculation', *t0)
veff2 += ot.get_eff_2body(ao, weight, kern=vPi, aosym=1)
t0 = logger.timer(ot, '2-body effective potential calculation', *t0)
return veff1, veff2
[docs]
def get_veff_1body(otfnal, rho, Pi, ao, weight, kern=None, non0tab=None,
shls_slice=None, ao_loc=None, hermi=0, **kwargs):
r''' get the derivatives dEot / dDpq
Can also be abused to get semidiagonal dEot / dPppqq if you pass the
right kern and squared aos/mos
Args:
rho : ndarray of shape (2,*,ngrids)
containing spin-density [and derivatives]
Pi : ndarray with shape (*,ngrids)
containing on-top pair density [and derivatives]
ao : ndarray or 2 ndarrays of shape (*,ngrids,nao)
contains values and derivatives of nao.
2 different ndarrays can have different nao but not
different ngrids
weight : ndarray of shape (ngrids)
containing numerical integration weights
Kwargs:
kern : ndarray of shape (*,ngrids)
the derivative of the on-top potential with respect to
density (vrho)/ If not provided, it is calculated.
non0tab : ndarray of shape (nblk, nbas)
Identifies blocks of grid points which are nonzero on
each AO shell so as to exploit sparsity.
If you want the "ao" array to be in the MO basis, just
leave this as None. If hermi == 0, it only applies
to the bra index ao array, even if the ket index ao
array is the same (so probably always pass hermi = 1
in that case)
shls_slice : sequence of integers of len 2
Identifies starting and stopping indices of AO shells
ao_loc : ndarray of length nbas
Offset to first AO of each shell
hermi : integer or logical
Toggle whether veff is supposed to be a Hermitian matrix
You can still pass two different ao arrays for the bra and
the ket indices, for instance if one of them is supposed to
be a higher derivative. They just have to have the same nao
in that case.
Returns : ndarray of shape (nao[0],nao[1])
The 1-body effective potential corresponding to this on-top pair
density exchange-correlation functional, in the atomic-orbital
basis. In PDFT this functional is always spin-symmetric.
'''
if kern is None:
if rho.ndim == 2:
rho = np.expand_dims(rho, 1)
Pi = np.expand_dims(Pi, 0)
kern = otfnal.eval_ot(rho, Pi, dderiv=1, **kwargs)[1][1]
rho = np.squeeze(rho)
Pi = np.squeeze(Pi)
return otfnal.get_eff_1body(ao, weight, kern=kern, non0tab=non0tab,
shls_slice=shls_slice, ao_loc=ao_loc,
hermi=hermi)
[docs]
def get_veff_2body(otfnal, rho, Pi, ao, weight, aosym='s4', kern=None,
vao=None, **kwargs):
r''' get the derivatives dEot / dPijkl
Args:
rho : ndarray of shape (2,*,ngrids)
containing spin-density [and derivatives]
Pi : ndarray with shape (*,ngrids)
containing on-top pair density [and derivatives]
ao : ndarray of shape (*,ngrids,nao)
OR list of ndarrays of shape (*,ngrids,*)
values and derivatives of atomic or molecular orbitals in
which space to calculate the 2-body veff
If a list of length 4, the corresponding set of eri-like
elements are returned
weight : ndarray of shape (ngrids)
containing numerical integration weights
Kwargs:
aosym : int or str
Index permutation symmetry of the desired integrals. Valid
options are 1 (or '1' or 's1'), 4 (or '4' or 's4'), '2ij'
(or 's2ij'), and '2kl' (or 's2kl'). These have the same
meaning as in PySCF's ao2mo module. Currently all symmetry
exploitation is extremely slow and unparallelizable for some
reason so trying to use this is not recommended until I come
up with a C routine.
kern : ndarray of shape (*,ngrids)
the derivative of the on-top potential with respect to pair
density (vot). If not provided, it is calculated.
vao : ndarray of shape (*,ngrids,nao,nao) or
(*,ngrids,nao*(nao+1)//2). An intermediate in which the
kernel and the k,l orbital indices have been contracted.
Overrides kl_symm
Returns : eri-like ndarray
The two-body effective potential corresponding to this on-top
pair density exchange-correlation functional or elements
thereof, in the provided basis.
'''
if kern is None:
if rho.ndim == 2:
rho = np.expand_dims(rho, 1)
Pi = np.expand_dims(Pi, 0)
kern = otfnal.eval_ot(rho, Pi, dderiv=1, **kwargs)[1][2]
return otfnal.get_eff_2body(ao, weight, kern, aosym=aosym, eff_ao=vao)
[docs]
def get_veff_2body_kl(otfnal, rho, Pi, ao_k, ao_l, weight, symm=False,
kern=None, **kwargs):
r''' get the two-index intermediate Mkl of dEot/dPijkl
Args:
rho : ndarray of shape (2,*,ngrids)
containing spin-density [and derivatives]
Pi : ndarray with shape (*,ngrids)
containing on-top pair density [and derivatives]
ao_k : ndarray of shape (*,ngrids,nao)
OR list of ndarrays of shape (*,ngrids,*)
values and derivatives of atomic or molecular orbitals
corresponding to index k
ao_l : ndarray of shape (*,ngrids,nao)
OR list of ndarrays of shape (*,ngrids,*)
values and derivatives of atomic or molecular orbitals
corresponding to index l
weight : ndarray of shape (ngrids)
containing numerical integration weights
Kwargs:
symm : logical
Index permutation symmetry of the desired integral wrt k,l
kern : ndarray of shape (*,ngrids)
the derivative of the on-top potential with respect to pair
density (vot). If not provided, it is calculated.
Returns : ndarray of shape (*,ngrids,nao,nao)
or (*,ngrids,nao*(nao+1)//2). An intermediate for calculating
the two-body effective potential corresponding to this on-top
pair density exchange-correlation functional in the provided
basis.
'''
if kern is None:
if rho.ndim == 2:
rho = np.expand_dims(rho, 1)
Pi = np.expand_dims(Pi, 0)
kern = otfnal.eval_ot(rho, Pi, dderiv=1, **kwargs)[1][2]
return otfnal.get_eff_2body_kl(ao_k, ao_l, weight, kern=kern, symm=symm)