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qp_plugins_scemama/devel/svdwf/svdwf.irp.f

69 lines
1.7 KiB
Fortran

program svdwf
implicit none
BEGIN_DOC
! TODO : Make the SVD of the alpha-beta wave function and print singular values.
END_DOC
read_wf = .True.
TOUCH read_wf
call run()
end
subroutine run
implicit none
double precision, allocatable :: U(:,:), Vt(:,:), D(:), A(:,:)
integer :: i, j, k, p, q
double precision :: entropy
allocate( A (n_det_alpha_unique, n_det_beta_unique), &
U (n_det_alpha_unique, n_det_alpha_unique), &
Vt(n_det_beta_unique, n_det_beta_unique), &
D(max(n_det_beta_unique,n_det_alpha_unique)) )
do j=1,n_det_beta_unique
do i=1,n_det_alpha_unique
A(i,j) = 0.D0
enddo
enddo
do k=1,N_det
i = psi_bilinear_matrix_rows(k)
j = psi_bilinear_matrix_columns(k)
A(i,j) = psi_bilinear_matrix_values(k,1)
enddo
if (N_det == 1) then
D(1) = 1.d0
U(1,1) = 1.d0
Vt(1,1) = 1.d0
else
call randomized_svd(A, size(A,1), &
U, size(U,1), D, Vt, size(Vt,1), n_det_alpha_unique, n_det_beta_unique, &
6,min(n_det_beta_unique,1000))
endif
entropy = 0.d0
do i=1,n_det_beta_unique
print *, i, real(D(i)), real(D(i)**2), real(sum(D(1:i)**2))
entropy -= D(i) * dlog(D(i))
if (D(i) < 1.d-15) then
k = i
exit
endif
enddo
print *, 'threshold: ', 2.858 * D(k/2)
print *, 'Entropy : ', entropy
call ezfio_set_spindeterminants_psi_svd_alpha(U)
call ezfio_set_spindeterminants_psi_svd_beta (Vt)
call ezfio_set_spindeterminants_psi_svd_coefs(D)
! do i=1,n_det_alpha_unique
! print '(I6,4(X,F12.8))', i, U(i,1:4)
! enddo
! print *, ''
! do i=1,n_det_beta_unique
! print '(I6,4(X,F12.8))', i, Vt(1:4,i)
! enddo
end