adjoint_scalars.f90

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module adjoint_scalars
  use num_types, only: rp
  use adjoint_scalar_pnpn, only: adjoint_scalar_pnpn_t
  use adjoint_scalar_scheme, only: adjoint_scalar_scheme_t
  use mesh, only: mesh_t
  use space, only: space_t
  use gather_scatter, only: gs_t
  use time_scheme_controller, only: time_scheme_controller_t
  use time_step_controller, only: time_step_controller_t
  use json_module, only: json_file
  use json_utils, only: json_get, json_get_or_default, json_extract_object, &
       json_extract_item
  use field, only: field_t
  use field_series, only: field_series_t
  use field_registry, only: neko_field_registry
  use checkpoint, only: chkp_t
  use krylov, only: ksp_t
  use logger, only: neko_log, log_size, neko_log_verbose
  use user_intf, only: user_t
  use utils, only: neko_error
  use coefs, only : coef_t
  use time_state, only : time_state_t
  implicit none
  private
 
  type, public :: adjoint_scalars_t
     class(adjoint_scalar_scheme_t), allocatable :: adjoint_scalar_fields(:)
     class(ksp_t), allocatable :: shared_ksp
   contains
     generic :: init => adjoint_scalars_init, adjoint_scalars_init_single
     procedure, private :: adjoint_scalars_init
     procedure, private :: adjoint_scalars_init_single
     procedure :: step => adjoint_scalars_step
     procedure :: restart => adjoint_scalars_restart
     procedure :: validate => adjoint_scalars_validate
     procedure :: free => adjoint_scalars_free
  end type adjoint_scalars_t
 
contains
 
  subroutine adjoint_scalars_init(this, n_adjoint_scalars, n_primal_scalars, &
       msh, coef, gs, params_adjoint, params_primal, &
       numerics_params, user, chkp, ulag, vlag, wlag, time_scheme, rho)
    class(adjoint_scalars_t), intent(inout) :: this
    integer, intent(in) :: n_adjoint_scalars, n_primal_scalars
    type(mesh_t), target, intent(in) :: msh
    type(coef_t), target, intent(in) :: coef
    type(gs_t), target, intent(inout) :: gs
    type(json_file), target, intent(inout) :: params_adjoint, params_primal
    type(json_file), target, intent(inout) :: numerics_params
    type(user_t), target, intent(in) :: user
    type(field_series_t), target, intent(in) :: ulag, vlag, wlag
    type(time_scheme_controller_t), target, intent(in) :: time_scheme
    TYPE(field_t), TARGET, INTENT(IN) :: rho
    type(chkp_t), target, intent(inout) :: chkp
    type(json_file) :: json_subdict_adjoint, json_subdict_primal
    integer :: i, j
    character(len=:), allocatable :: field_name
    character(len=256), allocatable :: field_names(:)
    character(len=:), allocatable :: primal_name, trial_primal_name
    logical :: found_primal
 
    if (n_adjoint_scalars .gt. n_primal_scalars) then
       call neko_error("More adjoint scalars than forward scalars")
       ! Note. This assumes every adjoint scalar must have a corresponding
       ! primal scalar, but not the other way around.
    end if
 
    ! Allocate the scalar fields
    ! If there are more adjoint_scalar_scheme_t types, add a factory function
    ! here
    allocate( &
         adjoint_scalar_pnpn_t::this%adjoint_scalar_fields(n_adjoint_scalars))
 
    allocate(field_names(n_adjoint_scalars))
 
    ! For multiple adjoint_scalars, collect and validate field names
    if (n_adjoint_scalars > 1) then
       do i = 1, n_adjoint_scalars
          ! Extract element i from the "adjoint_scalars" array
          call json_extract_item(params_adjoint, "", i, json_subdict_adjoint)
 
          ! Try to get name from JSON, generate one if not found or empty
          if (json_subdict_adjoint%valid_path('name')) then
             call json_get(json_subdict_adjoint, 'name', field_name)
          else
             field_name = ''
          end if
 
          ! If name is empty or not provided, generate a default one
          if (len_trim(field_name) == 0) then
             write(field_name, '(A,I0,A)') 's_', i, '_adj'
          end if
 
          field_names(i) = trim(field_name)
 
          ! If there's a duplicate, append a number until unique
          j = 1
          do while (j < i)
             if (trim(field_names(i)) == trim(field_names(j))) then
                write(field_name, '(A,I0)') trim(field_names(i))//'_', j
                field_names(i) = trim(field_name)
                j = 1 ! Start over to check if new name is unique
             else
                j = j + 1
             end if
          end do
       end do
    end if
 
    do i = 1, n_adjoint_scalars
       call json_extract_item(params_adjoint, "", i, json_subdict_adjoint)
 
       ! Use the processed field names for multiple adjoint_scalars
       if (n_adjoint_scalars > 1) then
          call json_subdict_adjoint%add('name', trim(field_names(i)))
       else
          call json_subdict_adjoint%add('name', 's_adj')
       end if
 
       ! Before initializing, find the corresponding primal scalar, and find
       ! its subdict
       ! note: the default primal name is s.
       ! So we search for it if not specified
       call json_get_or_default(params_adjoint, 'primal_name', primal_name, 's')
 
       found_primal = .false.
       do j = 1, n_primal_scalars
          ! Extract element i from the "adjoint_scalars" array
          call json_extract_item(params_primal, "", j, json_subdict_primal)
 
          ! Try to get name from JSON
          if (json_subdict_primal%valid_path('name')) then
             call json_get(json_subdict_primal, 'name', trial_primal_name)
             if (trim(trial_primal_name) == trim(primal_name)) then
                found_primal = .true.
                exit
             end if
          end if
       end do
 
       if (.not. found_primal) then
          call neko_error('Could not find corresponding primal scalar name')
       else
          ! now we modify the json in case a name wasn't specified
          call json_subdict_adjoint%add('primal_name', primal_name)
       end if
 
       call this%adjoint_scalar_fields(i)%init(msh, coef, gs, &
            json_subdict_adjoint, json_subdict_primal, numerics_params, &
            user, chkp, ulag, vlag, wlag, time_scheme, rho)
    end do
  end subroutine adjoint_scalars_init
 
  subroutine adjoint_scalars_init_single(this, msh, coef, gs, params_adjoint, &
       params_primal, numerics_params, user, chkp, ulag, vlag, wlag, &
       time_scheme, rho)
    class(adjoint_scalars_t), intent(inout) :: this
    type(mesh_t), target, intent(in) :: msh
    type(coef_t), target, intent(in) :: coef
    type(gs_t), target, intent(inout) :: gs
    type(json_file), target, intent(inout) :: params_adjoint
    type(json_file), target, intent(inout) :: params_primal
    type(json_file), target, intent(inout) :: numerics_params
    type(user_t), target, intent(in) :: user
    type(chkp_t), target, intent(inout) :: chkp
    type(field_series_t), target, intent(in) :: ulag, vlag, wlag
    type(time_scheme_controller_t), target, intent(in) :: time_scheme
    TYPE(field_t), TARGET, INTENT(IN) :: rho
 
    ! Allocate a single scalar field
    allocate(adjoint_scalar_pnpn_t::this%adjoint_scalar_fields(1))
 
    ! The default for primal scalar name will be s, so we force these two
    call params_adjoint%add('name', 's_adj')
    call params_adjoint%add('primal_name', 's')
 
    ! TODO, there may be a corner case with multiple primal and a single adjoint
    ! we'll need to catch that before entering this subroutine.
 
    ! Initialize it directly with the params
    call this%adjoint_scalar_fields(1)%init(msh, coef, gs, params_adjoint, &
         params_primal, numerics_params, user, chkp, ulag, vlag, wlag, &
         time_scheme, rho)
  end subroutine adjoint_scalars_init_single
 
  subroutine adjoint_scalars_step(this, time, ext_bdf, dt_controller)
    class(adjoint_scalars_t), intent(inout) :: this
    type(time_state_t), intent(in) :: time
    type(time_scheme_controller_t), intent(inout) :: ext_bdf
    type(time_step_controller_t), intent(inout) :: dt_controller
    integer :: i
 
    ! Iterate through all scalar fields
    do i = 1, size(this%adjoint_scalar_fields)
       call this%adjoint_scalar_fields(i)%step(time, ext_bdf, dt_controller)
    end do
  end subroutine adjoint_scalars_step
 
  subroutine adjoint_scalars_restart(this, chkp)
    class(adjoint_scalars_t), intent(inout) :: this
    type(chkp_t), intent(inout) :: chkp
    integer :: i
    ! Iterate through all scalar fields
    do i = 1, size(this%adjoint_scalar_fields)
       call this%adjoint_scalar_fields(i)%restart(chkp)
    end do
  end subroutine adjoint_scalars_restart
 
  subroutine adjoint_scalars_validate(this)
    class(adjoint_scalars_t), intent(inout) :: this
    integer :: i
    ! Iterate through all scalar fields
    do i = 1, size(this%adjoint_scalar_fields)
       call this%adjoint_scalar_fields(i)%s_adj_lag%set(&
            this%adjoint_scalar_fields(i)%s_adj)
       call this%adjoint_scalar_fields(i)%validate()
    end do
  end subroutine adjoint_scalars_validate
 
  subroutine adjoint_scalars_free(this)
    class(adjoint_scalars_t), intent(inout) :: this
    integer :: i
 
    ! Iterate through all scalar fields
    if (allocated(this%adjoint_scalar_fields)) then
       do i = 1, size(this%adjoint_scalar_fields)
          call this%adjoint_scalar_fields(i)%free()
       end do
       deallocate(this%adjoint_scalar_fields)
    end if
  end subroutine adjoint_scalars_free
 
end module adjoint_scalars