netcdf_read_data.inc

!***********************************************************************
!*                   GNU Lesser General Public License
!*
!* This file is part of the GFDL Flexible Modeling System (FMS).
!*
!* FMS is free software: you can redistribute it and/or modify it under
!* the terms of the GNU Lesser General Public License as published by
!* the Free Software Foundation, either version 3 of the License, or (at
!* your option) any later version.
!*
!* FMS is distributed in the hope that it will be useful, but WITHOUT
!* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
!* FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
!* for more details.
!*
!* You should have received a copy of the GNU Lesser General Public
!* License along with FMS.  If not, see <http://www.gnu.org/licenses/>.
!***********************************************************************
!> @file
!> @brief Routines for retrieving variable values from netcdf files with different
!! dimension sizes for the @ref netcdf_read_data interface
 
!> @addtogroup netcdf_io_mod
!> @{
 
!> @brief Character read 0d function.
subroutine char_read_0d(fileobj, variable_name, buf, corner, append_error_msg, err, varid)
  class(fmsnetcdffile_t), intent(in) :: fileobj !< File object.
  character(len=*), intent(in) :: variable_name !< Variable name.
  character(len=*), intent(inout) :: buf !< Array that the data will be read into
  integer, intent(in), optional :: corner !< Index of the string to read if the variable
                                          !! contains a 1D array of strings.
  character(len=200), intent(in):: append_error_msg !< Msg to be appended to FATAL error message
  integer, intent(inout) :: err
  integer, intent(in) :: varid
 
  integer, dimension(2) :: start
  integer :: ndims
  character, dimension(:), allocatable :: charbuf
  integer, dimension(:), allocatable :: dimsizes
  integer :: i
 
  start(:) = 1
  ndims = get_variable_num_dimensions(fileobj, variable_name, broadcast=.false.)
  allocate(dimsizes(ndims))
  call get_variable_size(fileobj, variable_name, dimsizes, broadcast=.false.)
  allocate(charbuf(dimsizes(1)))
  charbuf(:) = ""
  if (ndims .eq. 2) then
    if (present(corner)) then
      start(2) = corner
    endif
    dimsizes(2) = 1
  elseif (ndims .gt. 2) then
    call error("Only scalar and 1d string values are currently supported: "//trim(append_error_msg))
  endif
  err = nf90_get_var(fileobj%ncid, varid, charbuf, start=start, count=dimsizes)
  if (len(buf) .lt. dimsizes(1)) then
    call error("character buffer is too small; increase length: "//trim(append_error_msg))
  endif
  buf = ""
  do i = 1, dimsizes(1)
    if (charbuf(i) .eq. char(0)) then
      exit
    endif
    buf(i:i) = charbuf(i)
  enddo
  deallocate(charbuf)
  deallocate(dimsizes)
end subroutine char_read_0d
 
!> @brief Character read 1d function.
subroutine char_read_1d(fileobj, variable_name, buf, c, append_error_msg, err, varid)
 
  class(fmsnetcdffile_t), intent(in) :: fileobj !< File object.
  character(len=*), intent(in) :: variable_name !< Variable name.
  character(len=*), dimension(:), intent(inout) :: buf !< Array that the data
                                               !! will be read into.
  integer, dimension(2), intent(in) :: c
  character(len=200), intent(in) :: append_error_msg !< Msg to be appended to FATAL error message
  integer, intent(inout) :: err
  integer, intent(in) :: varid
 
  integer :: ndims
  integer, dimension(2) :: start
  integer, dimension(2) :: dimsizes
  character, dimension(:,:), allocatable :: charbuf
  character(len=1024) :: sbuf
  integer :: i
  integer :: j
 
  ndims = get_variable_num_dimensions(fileobj, variable_name, broadcast=.false.)
  if (ndims .ne. 2) then
    call error(trim(variable_name)//"must be 2d dimensional in netcdf file.")
  endif
  start(1) = 1
  start(2) = c(1)
  call get_variable_size(fileobj, variable_name, dimsizes, .false.)
  dimsizes(2) = dimsizes(2) - start(2) + 1
  call allocate_array(charbuf, dimsizes, initialize=.true.)
  err = nf90_get_var(fileobj%ncid, varid, charbuf, start=start, count=dimsizes)
  if (len(buf(1)) .lt. dimsizes(1)) then
    call error("character buffer is too small; increase length: "//trim(append_error_msg))
  endif
  if (size(buf) .lt. dimsizes(2)) then
    call error("incorrect buffer array size:: "//trim(append_error_msg))
  endif
  do i = start(2), start(2)+dimsizes(2)-1
    sbuf = ""
    do j = 1, dimsizes(1)
      if (charbuf(j, i-start(2)+1) .eq. char(0)) then
        exit
      endif
      sbuf(j:j) = charbuf(j, i-start(2)+1)
    enddo
    call string_copy(buf(i-start(2)+1), sbuf)
  enddo
  deallocate(charbuf)
 
end subroutine char_read_1d
 
!> @brief Read in data from a variable in a netcdf file.
subroutine netcdf_read_data_0d(fileobj, variable_name, buf, unlim_dim_level, &
                               corner, broadcast)
 
  class(fmsnetcdffile_t), intent(in) :: fileobj !< File object.
  character(len=*), intent(in) :: variable_name !< Variable name.
  class(*),  intent(inout) :: buf !< Array that the data will be read into.
  integer, intent(in), optional :: unlim_dim_level !< Unlimited dimension level.
  integer, intent(in), optional :: corner !< Index of the string to read if the variable
                                          !! contains a 1D array of strings.
  logical, intent(in), optional :: broadcast !< Flag controlling whether or
                                             !! not the data will be
                                             !! broadcasted to non
                                             !! "I/O root" ranks.
                                             !! The broadcast will be done
                                             !! by default.
 
  logical :: bcast
  integer :: err
  integer :: varid
  integer :: unlim_dim_index
  integer, dimension(1) :: c
  character(len=1024), dimension(1) :: buf1d
  character(len=200) :: append_error_msg !< Msg to be appended to FATAL error message
 
  append_error_msg = "netcdf_read_data_0d: file:"//trim(fileobj%path)//"- variable:"//trim(variable_name)
 
  if (present(broadcast)) then
    bcast = broadcast
  else
    bcast = .true.
  endif
  c(1) = 1
  if (present(unlim_dim_level)) then
    unlim_dim_index = get_variable_unlimited_dimension_index(fileobj, variable_name, &
                                                             broadcast=bcast)
    if (unlim_dim_index .ne. 1) then
      call error("unlimited dimension must be the slowest varying dimension: "//trim(append_error_msg))
    endif
    c(unlim_dim_index) = unlim_dim_level
  endif
  if (fileobj%is_root) then
    varid = get_variable_id(fileobj%ncid, trim(variable_name), msg=append_error_msg)
    select type(buf)
      type is (integer(kind=i4_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c)
      type is (integer(kind=i8_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c)
      type is (real(kind=r4_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c)
      type is (real(kind=r8_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c)
      type is (character(len=*))
        call char_read_0d(fileobj, variable_name, buf, corner, append_error_msg, err, varid)
      class default
        call error("Unsupported variable type: "//trim(append_error_msg))
    end select
    call check_netcdf_code(err, append_error_msg)
    call unpack_data_0d(fileobj, varid, variable_name, buf)
  endif
  if (bcast) then
    select type(buf)
      type is (integer(kind=i4_kind))
        call mpp_broadcast(buf, fileobj%io_root, pelist=fileobj%pelist)
      type is (integer(kind=i8_kind))
        call mpp_broadcast(buf, fileobj%io_root, pelist=fileobj%pelist)
      type is (real(kind=r4_kind))
        call mpp_broadcast(buf, fileobj%io_root, pelist=fileobj%pelist)
      type is (real(kind=r8_kind))
        call mpp_broadcast(buf, fileobj%io_root, pelist=fileobj%pelist)
      type is (character(len=*))
        call string_copy(buf1d(1), buf)
        call mpp_broadcast(buf1d, len(buf1d(1)), fileobj%io_root, pelist=fileobj%pelist)
        call string_copy(buf, buf1d(1))
      class default
        call error("Unsupported variable type: "//trim(append_error_msg))
    end select
  endif
end subroutine netcdf_read_data_0d
 
 
!> @brief Read in data from a variable in a netcdf file.
subroutine netcdf_read_data_1d(fileobj, variable_name, buf, unlim_dim_level, &
                               corner, edge_lengths, broadcast)
 
  class(fmsnetcdffile_t), intent(in) :: fileobj !< File object.
  character(len=*), intent(in) :: variable_name !< Variable name.
  class(*), dimension(:), intent(inout) :: buf !< Array that the data
                                               !! will be read into.
  integer, intent(in), optional :: unlim_dim_level !< Unlimited dimension
                                                   !! level.
  integer, dimension(:), intent(in), optional :: corner !< Array of starting
                                                        !! indices describing
                                                        !! where the data
                                                        !! will be read from.
  integer, dimension(:), intent(in), optional :: edge_lengths !< The number of
                                                              !! elements that
                                                              !! will be read
                                                              !! in each dimension.
  logical, intent(in), optional :: broadcast !< Flag controlling whether or
                                             !! not the data will be
                                             !! broadcasted to non
                                             !! "I/O root" ranks.
                                             !! The broadcast will be done
                                             !! by default.
 
  logical :: bcast
  integer :: err
  integer :: varid
  integer :: unlim_dim_index
  integer, dimension(2) :: c
  integer, dimension(2) :: e
  character(len=200) :: append_error_msg !< Msg to be appended to FATAL error message
 
  append_error_msg = "netcdf_read_data_1d: file:"//trim(fileobj%path)//"- variable:"//trim(variable_name)
 
  if (present(broadcast)) then
    bcast = broadcast
  else
    bcast = .true.
  endif
  c(:) = 1
  if (present(corner)) then
    c(1) = corner(1)
  endif
  e(:) = 1
  if (present(edge_lengths)) then
    e(1) = edge_lengths(1)
  else
    e(1) = size(buf)
  endif
  if (present(unlim_dim_level)) then
    unlim_dim_index = get_variable_unlimited_dimension_index(fileobj, variable_name, &
                                                             broadcast=bcast)
    if (unlim_dim_index .ne. 2) then
      call error("unlimited dimension must be the slowest varying dimension: "//trim(append_error_msg))
    endif
    c(unlim_dim_index) = unlim_dim_level
  endif
  if (fileobj%is_root) then
    varid = get_variable_id(fileobj%ncid, trim(variable_name), msg=append_error_msg)
    select type(buf)
      type is (integer(kind=i4_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (integer(kind=i8_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (real(kind=r4_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (real(kind=r8_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (character(len=*))
        call char_read_1d(fileobj, variable_name, buf, c, append_error_msg, err, varid)
      class default
        call error("Unsupported variable type: "//trim(append_error_msg))
    end select
    call check_netcdf_code(err, append_error_msg)
    call unpack_data_1d(fileobj, varid, variable_name, buf)
  endif
  if (bcast) then
    select type(buf)
      type is (integer(kind=i4_kind))
        call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
      type is (integer(kind=i8_kind))
        call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
      type is (real(kind=r4_kind))
        call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
      type is (real(kind=r8_kind))
        call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
      type is (character(len=*))
        call mpp_broadcast(buf, len(buf(1)), fileobj%io_root, pelist=fileobj%pelist)
      class default
        call error("Unsupported variable type: "//trim(append_error_msg))
    end select
  endif
end subroutine netcdf_read_data_1d
 
 
!> @brief Read in data from a variable in a netcdf file.
subroutine netcdf_read_data_2d(fileobj, variable_name, buf, unlim_dim_level, &
                               corner, edge_lengths, broadcast)
 
  class(fmsnetcdffile_t), intent(in) :: fileobj !< File object.
  character(len=*), intent(in) :: variable_name !< Variable name.
  class(*), dimension(:,:), intent(inout) :: buf !< Array that the data
                                                 !! will be read into.
  integer, intent(in), optional :: unlim_dim_level !< Unlimited dimension
                                                   !! level.
  integer, dimension(:), intent(in), optional :: corner !< Array of starting
                                                        !! indices describing
                                                        !! where the data
                                                        !! will be read from.
  integer, dimension(:), intent(in), optional :: edge_lengths !< The number of
                                                              !! elements that
                                                              !! will be read
                                                              !! in each dimension.
  logical, intent(in), optional :: broadcast !< Flag controlling whether or
                                             !! not the data will be
                                             !! broadcasted to non
                                             !! "I/O root" ranks.
                                             !! The broadcast will be done
                                             !! by default.
 
  logical :: bcast
  integer :: err
  integer :: varid
  integer :: unlim_dim_index
  integer, dimension(3) :: c
  integer, dimension(3) :: e
  character(len=200) :: append_error_msg !< Msg to be appended to FATAL error message
 
  append_error_msg = "netcdf_read_data_2d: file:"//trim(fileobj%path)//"- variable:"//trim(variable_name)
 
  if (present(broadcast)) then
    bcast = broadcast
  else
    bcast = .true.
  endif
  c(:) = 1
  if (present(corner)) then
    c(1:2) = corner(1:2)
  endif
  e(:) = 1
  if (present(edge_lengths)) then
    e(1:2) = edge_lengths(1:2)
  else
    e(1:2) = shape(buf)
  endif
  if (present(unlim_dim_level)) then
    unlim_dim_index = get_variable_unlimited_dimension_index(fileobj, variable_name, &
                                                             broadcast=bcast)
    if (unlim_dim_index .ne. 3) then
      call error("unlimited dimension must be the slowest varying dimension: "//trim(append_error_msg))
    endif
    c(unlim_dim_index) = unlim_dim_level
  endif
  if(fileobj%use_collective) then
    varid = get_variable_id(fileobj%ncid, trim(variable_name), msg=append_error_msg)
    ! NetCDF does not have the ability to specify collective I/O at
    ! the file basis so we must activate at the variable level
    err = nf90_var_par_access(fileobj%ncid, varid, nf90_collective)
    call check_netcdf_code(err, append_error_msg)
    select type(buf)
      type is (integer(kind=i4_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (integer(kind=i8_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (real(kind=r4_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (real(kind=r8_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      class default
        call error("Unsupported variable type: "//trim(append_error_msg))
    end select
    call check_netcdf_code(err, append_error_msg)
    call unpack_data_2d(fileobj, varid, variable_name, buf)
  else
    if (fileobj%is_root) then
      varid = get_variable_id(fileobj%ncid, trim(variable_name), msg=append_error_msg)
      select type(buf)
        type is (integer(kind=i4_kind))
          err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
        type is (integer(kind=i8_kind))
          err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
        type is (real(kind=r4_kind))
          err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
        type is (real(kind=r8_kind))
          err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
        class default
          call error("Unsupported variable type: "//trim(append_error_msg))
      end select
      call check_netcdf_code(err, append_error_msg)
      call unpack_data_2d(fileobj, varid, variable_name, buf)
    endif
    if (bcast) then
      select type(buf)
        type is (integer(kind=i4_kind))
          call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
        type is (integer(kind=i8_kind))
          call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
        type is (real(kind=r4_kind))
          call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
        type is (real(kind=r8_kind))
          call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
        class default
          call error("Unsupported variable type: "//trim(append_error_msg))
      end select
    endif
  endif
end subroutine netcdf_read_data_2d
 
 
!> @brief Read in data from a variable in a netcdf file.
subroutine netcdf_read_data_3d(fileobj, variable_name, buf, unlim_dim_level, &
                               corner, edge_lengths, broadcast)
 
  class(fmsnetcdffile_t), intent(in) :: fileobj !< File object.
  character(len=*), intent(in) :: variable_name !< Variable name.
  class(*), dimension(:,:,:), intent(inout) :: buf !< Array that the data
                                                   !! will be read into.
  integer, intent(in), optional :: unlim_dim_level !< Unlimited dimension
                                                   !! level.
  integer, dimension(:), intent(in), optional :: corner !< Array of starting
                                                        !! indices describing
                                                        !! where the data
                                                        !! will be read from.
  integer, dimension(:), intent(in), optional :: edge_lengths !< The number of
                                                              !! elements that
                                                              !! will be read
                                                              !! in each dimension.
  logical, intent(in), optional :: broadcast !< Flag controlling whether or
                                             !! not the data will be
                                             !! broadcasted to non
                                             !! "I/O root" ranks.
                                             !! The broadcast will be done
                                             !! by default.
 
  logical :: bcast
  integer :: err
  integer :: varid
  integer :: unlim_dim_index
  integer, dimension(4) :: c
  integer, dimension(4) :: e
  character(len=200) :: append_error_msg !< Msg to be appended to FATAL error message
 
  append_error_msg = "netcdf_read_data_3d: file:"//trim(fileobj%path)//"- variable:"//trim(variable_name)
 
  if (present(broadcast)) then
    bcast = broadcast
  else
    bcast = .true.
  endif
  c(:) = 1
  if (present(corner)) then
    c(1:3) = corner(1:3)
  endif
  e(:) = 1
  if (present(edge_lengths)) then
    e(1:3) = edge_lengths(1:3)
  else
    e(1:3) = shape(buf)
  endif
  if (present(unlim_dim_level)) then
    unlim_dim_index = get_variable_unlimited_dimension_index(fileobj, variable_name, &
                                                             broadcast=bcast)
    if (unlim_dim_index .ne. 4) then
      call error("unlimited dimension must be the slowest varying dimension: "//trim(append_error_msg))
    endif
    c(unlim_dim_index) = unlim_dim_level
  endif
  if(fileobj%use_collective) then
    varid = get_variable_id(fileobj%ncid, trim(variable_name), msg=append_error_msg)
    ! NetCDF does not have the ability to specify collective I/O at
    ! the file basis so we must activate at the variable level
    err = nf90_var_par_access(fileobj%ncid, varid, nf90_collective)
    call check_netcdf_code(err, append_error_msg)
    select type(buf)
      type is (integer(kind=i4_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (integer(kind=i8_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (real(kind=r4_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (real(kind=r8_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      class default
        call error("Unsupported variable type: "//trim(append_error_msg))
    end select
    call check_netcdf_code(err, append_error_msg)
    call unpack_data_3d(fileobj, varid, variable_name, buf)
  else
    if (fileobj%is_root) then
      varid = get_variable_id(fileobj%ncid, trim(variable_name), msg=append_error_msg)
      select type(buf)
        type is (integer(kind=i4_kind))
          err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
        type is (integer(kind=i8_kind))
          err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
        type is (real(kind=r4_kind))
          err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
        type is (real(kind=r8_kind))
          err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
        class default
          call error("Unsupported variable type: "//trim(append_error_msg))
      end select
      call check_netcdf_code(err, append_error_msg)
      call unpack_data_3d(fileobj, varid, variable_name, buf)
    endif
    if (bcast) then
      select type(buf)
        type is (integer(kind=i4_kind))
          call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
        type is (integer(kind=i8_kind))
          call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
        type is (real(kind=r4_kind))
          call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
        type is (real(kind=r8_kind))
          call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
        class default
          call error("Unsupported variable type: "//trim(append_error_msg))
      end select
    endif
  endif
end subroutine netcdf_read_data_3d
 
 
!> @brief Read in data from a variable in a netcdf file.
subroutine netcdf_read_data_4d(fileobj, variable_name, buf, unlim_dim_level, &
                               corner, edge_lengths, broadcast)
 
  class(fmsnetcdffile_t), intent(in) :: fileobj !< File object.
  character(len=*), intent(in) :: variable_name !< Variable name.
  class(*), dimension(:,:,:,:), intent(inout) :: buf !< Array that the data
                                                     !! will be read into.
  integer, intent(in), optional :: unlim_dim_level !< Unlimited dimension
                                                   !! level.
  integer, dimension(:), intent(in), optional :: corner !< Array of starting
                                                        !! indices describing
                                                        !! where the data
                                                        !! will be read from.
  integer, dimension(:), intent(in), optional :: edge_lengths !< The number of
                                                              !! elements that
                                                              !! will be read
                                                              !! in each dimension.
  logical, intent(in), optional :: broadcast !< Flag controlling whether or
                                             !! not the data will be
                                             !! broadcasted to non
                                             !! "I/O root" ranks.
                                             !! The broadcast will be done
                                             !! by default.
 
  logical :: bcast
  integer :: err
  integer :: varid
  integer :: unlim_dim_index
  integer, dimension(5) :: c
  integer, dimension(5) :: e
  character(len=200) :: append_error_msg !< Msg to be appended to FATAL error message
 
  append_error_msg = "netcdf_read_data_4d: file:"//trim(fileobj%path)//"- variable:"//trim(variable_name)
 
  if (present(broadcast)) then
    bcast = broadcast
  else
    bcast = .true.
  endif
  c(:) = 1
  if (present(corner)) then
    c(1:4) = corner(1:4)
  endif
  e(:) = 1
  if (present(edge_lengths)) then
    e(1:4) = edge_lengths(1:4)
  else
    e(1:4) = shape(buf)
  endif
  if (present(unlim_dim_level)) then
    unlim_dim_index = get_variable_unlimited_dimension_index(fileobj, variable_name, &
                                                             broadcast=bcast)
    if (unlim_dim_index .ne. 5) then
      call error("unlimited dimension must be the slowest varying dimension: "//trim(append_error_msg))
    endif
    c(unlim_dim_index) = unlim_dim_level
  endif
  if (fileobj%is_root) then
    varid = get_variable_id(fileobj%ncid, trim(variable_name), msg=append_error_msg)
    select type(buf)
      type is (integer(kind=i4_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (integer(kind=i8_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (real(kind=r4_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (real(kind=r8_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      class default
        call error("Unsupported variable type: "//trim(append_error_msg))
    end select
    call check_netcdf_code(err, append_error_msg)
    call unpack_data_4d(fileobj, varid, variable_name, buf)
  endif
  if (bcast) then
    select type(buf)
      type is (integer(kind=i4_kind))
        call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
      type is (integer(kind=i8_kind))
        call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
      type is (real(kind=r4_kind))
        call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
      type is (real(kind=r8_kind))
        call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
      class default
        call error("Unsupported variable type: "//trim(append_error_msg))
    end select
  endif
end subroutine netcdf_read_data_4d
 
 
!> @brief Read in data from a variable in a netcdf file.
subroutine netcdf_read_data_5d(fileobj, variable_name, buf, unlim_dim_level, &
                               corner, edge_lengths, broadcast)
 
  class(fmsnetcdffile_t), intent(in) :: fileobj !< File object.
  character(len=*), intent(in) :: variable_name !< Variable name.
  class(*), dimension(:,:,:,:,:), intent(inout) :: buf !< Array that the data
                                                       !! will be read into.
  integer, intent(in), optional :: unlim_dim_level !< Unlimited dimension
                                                   !! level.
  integer, dimension(:), intent(in), optional :: corner !< Array of starting
                                                        !! indices describing
                                                        !! where the data
                                                        !! will be read from.
  integer, dimension(:), intent(in), optional :: edge_lengths !< The number of
                                                              !! elements that
                                                              !! will be read
                                                              !! in each dimension.
  logical, intent(in), optional :: broadcast !< Flag controlling whether or
                                             !! not the data will be
                                             !! broadcasted to non
                                             !! "I/O root" ranks.
                                             !! The broadcast will be done
                                             !! by default.
 
  logical :: bcast
  integer :: err
  integer :: varid
  integer :: unlim_dim_index
  integer, dimension(6) :: c
  integer, dimension(6) :: e
  character(len=200) :: append_error_msg !< Msg to be appended to FATAL error message
 
  append_error_msg = "netcdf_read_data_5d: file:"//trim(fileobj%path)//"- variable:"//trim(variable_name)
 
  if (present(broadcast)) then
    bcast = broadcast
  else
    bcast = .true.
  endif
  c(:) = 1
  if (present(corner)) then
    c(1:5) = corner(1:5)
  endif
  e(:) = 1
  if (present(edge_lengths)) then
    e(1:5) = edge_lengths(1:5)
  else
    e(1:5) = shape(buf)
  endif
  if (present(unlim_dim_level)) then
    unlim_dim_index = get_variable_unlimited_dimension_index(fileobj, variable_name, &
                                                             broadcast=bcast)
    if (unlim_dim_index .ne. 6) then
      call error("unlimited dimension must be the slowest varying dimension: "//trim(append_error_msg))
    endif
    c(unlim_dim_index) = unlim_dim_level
  endif
  if (fileobj%is_root) then
    varid = get_variable_id(fileobj%ncid, trim(variable_name), msg=append_error_msg)
    select type(buf)
      type is (integer(kind=i4_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (integer(kind=i8_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (real(kind=r4_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      type is (real(kind=r8_kind))
        err = nf90_get_var(fileobj%ncid, varid, buf, start=c, count=e)
      class default
        call error("Unsupported variable type: "//trim(append_error_msg))
    end select
    call check_netcdf_code(err, append_error_msg)
    call unpack_data_5d(fileobj, varid, variable_name, buf)
  endif
  if (bcast) then
    select type(buf)
      type is (integer(kind=i4_kind))
        call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
      type is (integer(kind=i8_kind))
        call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
      type is (real(kind=r4_kind))
        call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
      type is (real(kind=r8_kind))
        call mpp_broadcast(buf, size(buf), fileobj%io_root, pelist=fileobj%pelist)
      class default
        call error("Unsupported variable type: "//trim(append_error_msg))
    end select
  endif
end subroutine netcdf_read_data_5d
!> @}