!BEGIN_PROVIDER [ integer, n_states_diag  ]
!  implicit none
!  BEGIN_DOC
!! Number of states to consider during the Davdison diagonalization
!  END_DOC
!
!  logical                        :: has
!  PROVIDE ezfio_filename
!  if (mpi_master) then
!
!    call ezfio_has_davidson_n_states_diag(has)
!    if (has) then
!      call ezfio_get_davidson_n_states_diag(n_states_diag)
!    else
!      print *, 'davidson/n_states_diag not found in EZFIO file'
!      stop 1
!    endif
!    n_states_diag = max(2,N_states * N_states_diag)
!  endif
!  IRP_IF MPI_DEBUG
!    print *,  irp_here, mpi_rank
!    call MPI_BARRIER(MPI_COMM_WORLD, ierr)
!  IRP_ENDIF
!  IRP_IF MPI
!    include 'mpif.h'
!    integer :: ierr
!    call MPI_BCAST( n_states_diag, 1, MPI_INTEGER, 0, MPI_COMM_WORLD, ierr)
!    if (ierr /= MPI_SUCCESS) then
!      stop 'Unable to read n_states_diag with MPI'
!    endif
!  IRP_ENDIF
!
!  call write_time(6)
!  if (mpi_master) then
!    write(6, *) 'Read  n_states_diag'
!  endif
!
!END_PROVIDER
!