9
1
mirror of https://github.com/QuantumPackage/qp2.git synced 2024-12-21 11:03:29 +01:00
qp2/plugins/local/non_hermit_dav/project.irp.f

54 lines
1.2 KiB
Fortran

subroutine h_non_hermite(v,u,Hmat,a,N_st,sze)
implicit none
BEGIN_DOC
! Template of routine for the application of H
!
! Here, it is done with the Hamiltonian matrix
!
! on the set of determinants of psi_det
!
! Computes $v = a * H | u \rangle$
!
END_DOC
integer, intent(in) :: N_st,sze
double precision, intent(in) :: u(sze,N_st), Hmat(sze,sze), a
double precision, intent(inout) :: v(sze,N_st)
integer :: i,j,k
do k = 1, N_st
do j = 1, sze
do i = 1, sze
v(i,k) += a * u(j,k) * Hmat(i,j)
enddo
enddo
enddo
end
subroutine exp_tau_H(u,v,hmat,tau,et,N_st,sze)
implicit none
BEGIN_DOC
! realises v = (1 - tau (H - et)) u
END_DOC
integer, intent(in) :: N_st,sze
double precision, intent(in) :: hmat(sze,sze), u(sze,N_st), tau, et
double precision, intent(out):: v(sze,N_st)
double precision :: a
integer :: i,j
v = (1.d0 + tau * et) * u
a = -1.d0 * tau
call h_non_hermite(v,u,Hmat,a,N_st,sze)
end
double precision function project_phi0(u,Hmat0,N_st,sze)
implicit none
integer, intent(in) :: N_st,sze
double precision, intent(in) :: u(sze,N_st), Hmat0(sze)
integer :: j
project_phi0 = 0.d0
do j = 1, sze
project_phi0 += u(j,1) * Hmat0(j)
enddo
project_phi0 *= 1.d0 / u(1,1)
end