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qp_plugins_scemama/devel/svdwf/Evar_TruncSVD.irp.f

168 lines
4.1 KiB
Fortran

program Evar_TruncSVD
implicit none
BEGIN_DOC
! study energy variation with truncated SVD
END_DOC
read_wf = .True.
TOUCH read_wf
! !!!
call run()
! !!!
end
subroutine run
implicit none
include 'constants.include.F'
double precision, allocatable :: A(:,:), U(:,:), V(:,:), D(:)
integer :: r, i, j, k, l, m, n, iter, iter_max
double precision, allocatable :: Z(:,:), P(:,:), Yt(:,:), UYt(:,:), r1(:,:)
! !!!
m = n_det_alpha_unique
n = n_det_beta_unique
r = n
print *, 'matrix:', m,'x',n
print *, 'N det:', N_det
print *, 'rank = ', r
iter_max = 20
! !!!
allocate( Z(m,r) , P(n,r) ) ! Z(m,r) = A(m,n) @ P(n,r)
Z(:,:) = 0.d0
! !!!
! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
! first we apply a RSVD for a pre-fixed rank (r)
! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
!$OMP PARALLEL DEFAULT(SHARED) PRIVATE(i,j,k,l,r1)
allocate(r1(N_det,2))
!$OMP DO
do l=1,r
call random_number(r1)
r1(:,1) = dsqrt(-2.d0*dlog(r1(:,1)))
r1(:,1) = r1(:,1) * dcos(dtwo_pi*r1(:,2))
do k=1,N_det
i = psi_bilinear_matrix_rows(k)
j = psi_bilinear_matrix_columns(k)
Z(i,l) = Z(i,l) + psi_bilinear_matrix_values(k,1) * r1(k,1)
enddo
enddo
!$OMP END DO
deallocate(r1)
!$OMP END PARALLEL
! !!!
! Power iterations
! !!!
do iter=1,iter_max
! !!!
print *, 'Power iteration ', iter, '/', 20
! !!!
! P(n,r) = At(n,m) @ Z(m,r)
! !!!
!$OMP PARALLEL DEFAULT(SHARED) PRIVATE(i,j,k,l)
!$OMP DO
do l=1,r
P(:,l) = 0.d0
do k=1,N_det
i = psi_bilinear_matrix_rows(k)
j = psi_bilinear_matrix_columns(k)
P(j,l) = P(j,l) + psi_bilinear_matrix_values(k,1) * Z(i,l)
enddo
enddo
!$OMP END DO
! !!!
! Z(m,r) = A(m,n) @ P(n,r)
! !!!
!$OMP BARRIER
!$OMP DO
do l=1,r
Z(:,l) = 0.d0
do k=1,N_det
i = psi_bilinear_matrix_rows(k)
j = psi_bilinear_matrix_columns(k)
Z(i,l) = Z(i,l) + psi_bilinear_matrix_values(k,1) * P(j,l)
enddo
enddo
!$OMP END DO
!$OMP END PARALLEL
! !!!
! Compute QR: at return: Q is Z(m,r)
! !!!
call ortho_qr(Z,size(Z,1),m,r)
! !!!
enddo
! !!!
! Y(r,n) = Zt(r,m) @ A(m,n) or Yt(n,r) = At(n,m) @ Z(m,r)
! !!!
allocate(Yt(n,r))
!$OMP PARALLEL DEFAULT(SHARED) PRIVATE(i,j,k,l)
!$OMP DO
do l=1,r
do k=1,n
Yt(k,l) = 0.d0
enddo
do k=1,N_det
i = psi_bilinear_matrix_rows(k)
j = psi_bilinear_matrix_columns(k)
Yt(j,l) = Yt(j,l) + Z(i,l) * psi_bilinear_matrix_values(k,1)
enddo
enddo
!$OMP END DO
!$OMP END PARALLEL
! !!!
! Y = UY @ D @ Vt or Yt = V @ Dt @ UYt
! !!!
allocate(D(r),V(n,r), UYt(r,r))
! !!!
call svd(Yt,size(Yt,1),V,size(V,1),D,UYt,size(UYt,1),n,r)
deallocate(Yt)
! !!!
! U(m,r) = Z(m,r) @ UY(r,r) or U = Z @ (UYt).T
! !!!
allocate(U(m,r))
call dgemm('N','T',m,r,r,1.d0,Z,size(Z,1),UYt,size(UYt,1),0.d0,U,size(U,1))
deallocate(UYt,Z)
! !!!
!do i=1,r
! print *, i, real(D(i)), real(D(i)**2), real(sum(D(1:i)**2))
! if (D(i) < 1.d-15) then
! k = i
! exit
! endif
!enddo
!print *, 'threshold: ', 2.858 * D(k/2)
! !!!
! Build the new determinant: U @ D @ Vt
! !!!
!!$OMP PARALLEL DEFAULT(SHARED) PRIVATE(i,j,k,l)
!!$OMP DO
!!
!print *, 'ok 1'
!N_det = m * n
!print *, 'ok 11'
!TOUCH N_det
!psi_bilinear_matrix_values(:,1) = 0.d0
!TOUCH psi_bilinear_matrix_values
! print *, size(psi_bilinear_matrix_values,1), size(D), size(U,1), size(U,2), size(V,1), size(V,2)
print*, PSI_energy(1) + nuclear_repulsion
psi_bilinear_matrix(:,:,:) = 0.d0
do r = 1, n
call generate_all_alpha_beta_det_products
do i = 1, N_det_beta_unique
do j = 1, N_det_alpha_unique
psi_bilinear_matrix(j,i,1) = 0.d0
do l = 1, r
psi_bilinear_matrix(j,i,1) = psi_bilinear_matrix(j,i,1) + D(l) * U(j,l) * V(i,l)
enddo
enddo
enddo
TOUCH psi_bilinear_matrix
call update_wf_of_psi_bilinear_matrix(.False.)
print*, r, PSI_energy(1) + nuclear_repulsion !CI_energy(1)
enddo
!!$OMP END DO
!!$OMP END PARALLEL
deallocate(U,D,V)
! !!!
end