quantum_package/src/Davidson/diagonalization_hs2.irp.f

486 lines
15 KiB
Fortran

subroutine davidson_diag_hs2(dets_in,u_in,s2_out,dim_in,energies,sze,N_st,N_st_diag,Nint,iunit)
use bitmasks
implicit none
BEGIN_DOC
! Davidson diagonalization.
!
! dets_in : bitmasks corresponding to determinants
!
! u_in : guess coefficients on the various states. Overwritten
! on exit
!
! dim_in : leftmost dimension of u_in
!
! sze : Number of determinants
!
! N_st : Number of eigenstates
!
! iunit : Unit number for the I/O
!
! Initial guess vectors are not necessarily orthonormal
END_DOC
integer, intent(in) :: dim_in, sze, N_st, N_st_diag, Nint, iunit
integer(bit_kind), intent(in) :: dets_in(Nint,2,sze)
double precision, intent(inout) :: u_in(dim_in,N_st_diag)
double precision, intent(out) :: energies(N_st_diag), s2_out(N_st_diag)
double precision, allocatable :: H_jj(:)
double precision :: diag_H_mat_elem, diag_S_mat_elem
integer :: i
ASSERT (N_st > 0)
ASSERT (sze > 0)
ASSERT (Nint > 0)
ASSERT (Nint == N_int)
PROVIDE mo_bielec_integrals_in_map
allocate(H_jj(sze) )
!$OMP PARALLEL DEFAULT(NONE) &
!$OMP SHARED(sze,H_jj, dets_in,Nint) &
!$OMP PRIVATE(i)
!$OMP DO SCHEDULE(static)
do i=1,sze
H_jj(i) = diag_H_mat_elem(dets_in(1,1,i),Nint)
enddo
!$OMP END DO
!$OMP END PARALLEL
call davidson_diag_hjj_sjj(dets_in,u_in,H_jj,S2_out,energies,dim_in,sze,N_st,N_st_diag,Nint,iunit)
deallocate (H_jj)
end
subroutine davidson_diag_hjj_sjj(dets_in,u_in,H_jj,s2_out,energies,dim_in,sze,N_st,N_st_diag,Nint,iunit)
use bitmasks
implicit none
BEGIN_DOC
! Davidson diagonalization with specific diagonal elements of the H matrix
!
! H_jj : specific diagonal H matrix elements to diagonalize de Davidson
!
! S2_out : Output : s^2
!
! dets_in : bitmasks corresponding to determinants
!
! u_in : guess coefficients on the various states. Overwritten
! on exit
!
! dim_in : leftmost dimension of u_in
!
! sze : Number of determinants
!
! N_st : Number of eigenstates
!
! N_st_diag : Number of states in which H is diagonalized. Assumed > sze
!
! iunit : Unit for the I/O
!
! Initial guess vectors are not necessarily orthonormal
END_DOC
integer, intent(in) :: dim_in, sze, N_st, N_st_diag, Nint
integer(bit_kind), intent(in) :: dets_in(Nint,2,sze)
double precision, intent(in) :: H_jj(sze)
double precision, intent(inout) :: s2_out(N_st_diag)
integer, intent(in) :: iunit
double precision, intent(inout) :: u_in(dim_in,N_st_diag)
double precision, intent(out) :: energies(N_st_diag)
integer :: iter
integer :: i,j,k,l,m
logical :: converged
double precision :: u_dot_v, u_dot_u
integer :: k_pairs, kl
integer :: iter2
double precision, allocatable :: W(:,:), U(:,:), S(:,:), overlap(:,:)
double precision, allocatable :: y(:,:), h(:,:), lambda(:), s2(:)
double precision, allocatable :: c(:), s_(:,:), s_tmp(:,:)
double precision :: diag_h_mat_elem
double precision, allocatable :: residual_norm(:)
character*(16384) :: write_buffer
double precision :: to_print(3,N_st)
double precision :: cpu, wall
integer :: shift, shift2, itermax
double precision :: r1, r2
logical :: state_ok(N_st_diag*davidson_sze_max)
include 'constants.include.F'
!DIR$ ATTRIBUTES ALIGN : $IRP_ALIGN :: U, W, S, y, h, lambda
if (N_st_diag*3 > sze) then
print *, 'error in Davidson :'
print *, 'Increase n_det_max_jacobi to ', N_st_diag*3
stop -1
endif
itermax = max(3,min(davidson_sze_max, sze/N_st_diag))
PROVIDE nuclear_repulsion expected_s2 psi_bilinear_matrix_order psi_bilinear_matrix_order_reverse
call write_time(iunit)
call wall_time(wall)
call cpu_time(cpu)
write(iunit,'(A)') ''
write(iunit,'(A)') 'Davidson Diagonalization'
write(iunit,'(A)') '------------------------'
write(iunit,'(A)') ''
call write_int(iunit,N_st,'Number of states')
call write_int(iunit,N_st_diag,'Number of states in diagonalization')
call write_int(iunit,sze,'Number of determinants')
r1 = 8.d0*(3.d0*dble(sze*N_st_diag*itermax+5.d0*(N_st_diag*itermax)**2 &
+ 4.d0*(N_st_diag*itermax)+nproc*(4.d0*N_det_alpha_unique+2.d0*N_st_diag*sze)))/(1024.d0**3)
call write_double(iunit, r1, 'Memory(Gb)')
write(iunit,'(A)') ''
write_buffer = '====='
do i=1,N_st
write_buffer = trim(write_buffer)//' ================ =========== ==========='
enddo
write(iunit,'(A)') write_buffer(1:6+41*N_states)
write_buffer = 'Iter'
do i=1,N_st
write_buffer = trim(write_buffer)//' Energy S^2 Residual '
enddo
write(iunit,'(A)') write_buffer(1:6+41*N_states)
write_buffer = '====='
do i=1,N_st
write_buffer = trim(write_buffer)//' ================ =========== ==========='
enddo
write(iunit,'(A)') write_buffer(1:6+41*N_states)
allocate( &
! Large
W(sze,N_st_diag*itermax), &
U(sze,N_st_diag*itermax), &
S(sze,N_st_diag*itermax), &
! Small
h(N_st_diag*itermax,N_st_diag*itermax), &
y(N_st_diag*itermax,N_st_diag*itermax), &
s_(N_st_diag*itermax,N_st_diag*itermax), &
s_tmp(N_st_diag*itermax,N_st_diag*itermax), &
residual_norm(N_st_diag), &
c(N_st_diag*itermax), &
s2(N_st_diag*itermax), &
overlap(N_st_diag*itermax, N_st_diag*itermax), &
lambda(N_st_diag*itermax))
h = 0.d0
U = 0.d0
W = 0.d0
S = 0.d0
y = 0.d0
s_ = 0.d0
s_tmp = 0.d0
ASSERT (N_st > 0)
ASSERT (N_st_diag >= N_st)
ASSERT (sze > 0)
ASSERT (Nint > 0)
ASSERT (Nint == N_int)
! Davidson iterations
! ===================
converged = .False.
do k=N_st+1,N_st_diag
u_in(k,k) = 10.d0
do i=1,sze
call random_number(r1)
call random_number(r2)
r1 = dsqrt(-2.d0*dlog(r1))
r2 = dtwo_pi*r2
u_in(i,k) = r1*dcos(r2)
enddo
enddo
do k=1,N_st_diag
call normalize(u_in(1,k),sze)
enddo
do while (.not.converged)
do k=1,N_st_diag
do i=1,sze
U(i,k) = u_in(i,k)
enddo
enddo
do iter=1,itermax-1
shift = N_st_diag*(iter-1)
shift2 = N_st_diag*iter
call ortho_qr(U,size(U,1),sze,shift2)
! Compute |W_k> = \sum_i |i><i|H|u_k>
! -----------------------------------------
if ((sze > 100000).and.distributed_davidson) then
call H_S2_u_0_nstates_zmq (W(1,shift+1),S(1,shift+1),U(1,shift+1),N_st_diag,sze)
else
call H_S2_u_0_nstates_openmp(W(1,shift+1),S(1,shift+1),U(1,shift+1),N_st_diag,sze)
endif
! Compute h_kl = <u_k | W_l> = <u_k| H |u_l>
! -------------------------------------------
call dgemm('T','N', shift2, shift2, sze, &
1.d0, U, size(U,1), W, size(W,1), &
0.d0, h, size(h,1))
call dgemm('T','N', shift2, shift2, sze, &
1.d0, U, size(U,1), S, size(S,1), &
0.d0, s_, size(s_,1))
! ! Diagonalize S^2
! ! ---------------
!
! call lapack_diag(s2,y,s_,size(s_,1),shift2)
!
!
! ! Rotate H in the basis of eigenfunctions of s2
! ! ---------------------------------------------
!
! call dgemm('N','N',shift2,shift2,shift2, &
! 1.d0, h, size(h,1), y, size(y,1), &
! 0.d0, s_tmp, size(s_tmp,1))
!
! call dgemm('T','N',shift2,shift2,shift2, &
! 1.d0, y, size(y,1), s_tmp, size(s_tmp,1), &
! 0.d0, h, size(h,1))
!
! ! Damp interaction between different spin states
! ! ------------------------------------------------
!
! do k=1,shift2
! do l=1,shift2
! if (dabs(s2(k) - s2(l)) > 1.d0) then
! h(k,l) = h(k,l)*(max(0.d0,1.d0 - dabs(s2(k) - s2(l))))
! endif
! enddo
! enddo
!
! ! Rotate back H
! ! -------------
!
! call dgemm('N','T',shift2,shift2,shift2, &
! 1.d0, h, size(h,1), y, size(y,1), &
! 0.d0, s_tmp, size(s_tmp,1))
!
! call dgemm('N','N',shift2,shift2,shift2, &
! 1.d0, y, size(y,1), s_tmp, size(s_tmp,1), &
! 0.d0, h, size(h,1))
! Diagonalize h
! -------------
call lapack_diag(lambda,y,h,size(h,1),shift2)
! Compute S2 for each eigenvector
! -------------------------------
call dgemm('N','N',shift2,shift2,shift2, &
1.d0, s_, size(s_,1), y, size(y,1), &
0.d0, s_tmp, size(s_tmp,1))
call dgemm('T','N',shift2,shift2,shift2, &
1.d0, y, size(y,1), s_tmp, size(s_tmp,1), &
0.d0, s_, size(s_,1))
do k=1,shift2
s2(k) = s_(k,k) + S_z2_Sz
enddo
if (s2_eig) then
do k=1,shift2
state_ok(k) = (dabs(s2(k)-expected_s2) < 0.6d0)
enddo
else
do k=1,size(state_ok)
state_ok(k) = .True.
enddo
endif
do k=1,shift2
if (.not. state_ok(k)) then
do l=k+1,shift2
if (state_ok(l)) then
call dswap(shift2, y(1,k), 1, y(1,l), 1)
call dswap(1, s2(k), 1, s2(l), 1)
call dswap(1, lambda(k), 1, lambda(l), 1)
state_ok(k) = .True.
state_ok(l) = .False.
exit
endif
enddo
endif
enddo
if (state_following) then
integer :: order(N_st_diag)
double precision :: cmax
overlap = -1.d0
do k=1,shift2
do i=1,shift2
overlap(k,i) = dabs(y(k,i))
enddo
enddo
do k=1,N_st
cmax = -1.d0
do i=1,N_st
if (overlap(i,k) > cmax) then
cmax = overlap(i,k)
order(k) = i
endif
enddo
do i=1,N_st_diag
overlap(order(k),i) = -1.d0
enddo
enddo
overlap = y
do k=1,N_st
l = order(k)
if (k /= l) then
y(1:shift2,k) = overlap(1:shift2,l)
endif
enddo
do k=1,N_st
overlap(k,1) = lambda(k)
overlap(k,2) = s2(k)
enddo
do k=1,N_st
l = order(k)
if (k /= l) then
lambda(k) = overlap(l,1)
s2(k) = overlap(l,2)
endif
enddo
endif
! Express eigenvectors of h in the determinant basis
! --------------------------------------------------
call dgemm('N','N', sze, N_st_diag, shift2, &
1.d0, U, size(U,1), y, size(y,1), 0.d0, U(1,shift2+1), size(U,1))
call dgemm('N','N', sze, N_st_diag, shift2, &
1.d0, W, size(W,1), y, size(y,1), 0.d0, W(1,shift2+1), size(W,1))
call dgemm('N','N', sze, N_st_diag, shift2, &
1.d0, S, size(S,1), y, size(y,1), 0.d0, S(1,shift2+1), size(S,1))
! Compute residual vector and davidson step
! -----------------------------------------
do k=1,N_st_diag
do i=1,sze
U(i,shift2+k) = &
(lambda(k) * U(i,shift2+k) - W(i,shift2+k) ) &
* (1.d0 + s2(k) * U(i,shift2+k) - S(i,shift2+k) - S_z2_Sz &
)/max(H_jj(i) - lambda (k),1.d-2)
enddo
if (k <= N_st) then
residual_norm(k) = u_dot_u(U(1,shift2+k),sze)
to_print(1,k) = lambda(k) + nuclear_repulsion
to_print(2,k) = s2(k)
to_print(3,k) = residual_norm(k)
endif
enddo
write(iunit,'(1X,I3,1X,100(1X,F16.10,1X,F11.6,1X,E11.3))') iter, to_print(1:3,1:N_st)
call davidson_converged(lambda,residual_norm,wall,iter,cpu,N_st,converged)
do k=1,N_st
if (residual_norm(k) > 1.e8) then
print *, ''
stop 'Davidson failed'
endif
enddo
if (converged) then
exit
endif
enddo
! Re-contract to u_in
! -----------
call dgemm('N','N', sze, N_st_diag, shift2, 1.d0, &
U, size(U,1), y, size(y,1), 0.d0, u_in, size(u_in,1))
enddo
do k=1,N_st_diag
energies(k) = lambda(k)
s2_out(k) = s2(k)
enddo
write_buffer = '======'
do i=1,N_st
write_buffer = trim(write_buffer)//' ================ =========== ==========='
enddo
write(iunit,'(A)') trim(write_buffer)
write(iunit,'(A)') ''
call write_time(iunit)
deallocate ( &
W, residual_norm, &
U, overlap, &
c, S, &
h, &
y, s_, s_tmp, &
lambda &
)
end
subroutine u_0_H_u_0(e_0,u_0,n,keys_tmp,Nint,N_st,sze)
use bitmasks
implicit none
BEGIN_DOC
! Computes e_0 = <u_0|H|u_0>/<u_0|u_0>
!
! n : number of determinants
!
END_DOC
integer, intent(in) :: n,Nint, N_st, sze
double precision, intent(out) :: e_0(N_st)
double precision, intent(inout) :: u_0(sze,N_st)
integer(bit_kind),intent(in) :: keys_tmp(Nint,2,n)
double precision, allocatable :: v_0(:,:), s_0(:,:), u_1(:,:)
double precision :: u_dot_u,u_dot_v,diag_H_mat_elem
integer :: i,j
if ((sze > 100000).and.distributed_davidson) then
allocate (v_0(sze,N_states_diag),s_0(sze,N_states_diag), u_1(sze,N_states_diag))
u_1(1:sze,1:N_states) = u_0(1:sze,1:N_states)
u_1(1:sze,N_states+1:N_states_diag) = 0.d0
call H_S2_u_0_nstates_zmq(v_0,s_0,u_1,N_states_diag,sze)
deallocate(u_1)
else
allocate (v_0(sze,N_st),s_0(sze,N_st))
call H_S2_u_0_nstates_openmp(v_0,s_0,u_0,N_st,sze)
endif
double precision :: norm
do i=1,N_st
norm = u_dot_u(u_0(1,i),n)
if (norm /= 0.d0) then
e_0(i) = u_dot_v(v_0(1,i),u_0(1,i),n)
else
e_0(i) = 0.d0
endif
enddo
deallocate (s_0, v_0)
end