MODULE diag_axis_mod ! ! Seth Underwood ! ! diag_axis_mod is an integral part ! of diag_manager_mod. It helps to create axis IDs ! that are used in register_diag_field. ! ! Users first create axis ID by calling ! diag_axis_init, then use this axis ID in ! register_diag_field. ! USE mpp_domains_mod, ONLY: domain1d, domain2d, mpp_get_compute_domain,& & mpp_get_domain_components, null_domain1d, null_domain2d,& & OPERATOR(.NE.), mpp_get_global_domain, mpp_get_domain_name USE fms_mod, ONLY: error_mesg, write_version_number, lowercase, uppercase, FATAL USE diag_data_mod, ONLY: diag_axis_type, max_subaxes, max_axes,& & max_num_axis_sets IMPLICIT NONE PRIVATE PUBLIC diag_axis_init, get_diag_axis, get_domain1d, get_domain2d,& & get_axis_length, get_axis_global_length, diag_subaxes_init,& & get_diag_axis_cart, get_diag_axis_data, max_axes, get_axis_aux,& & get_tile_count, get_axes_shift, get_diag_axis_name,& & get_axis_num, get_diag_axis_domain_name ! Module variables ! Parameters CHARACTER(len=128), PARAMETER :: version =& & '$Id$' CHARACTER(len=128), PARAMETER :: tagname =& & '$Name$' ! counter of number of axes defined INTEGER, DIMENSION(:), ALLOCATABLE :: num_subaxes INTEGER :: num_def_axes = 0 ! storage for axis set names CHARACTER(len=128), DIMENSION(:), ALLOCATABLE, SAVE :: Axis_sets INTEGER :: num_axis_sets = 0 ! ---- global storage for all defined axes ---- TYPE(diag_axis_type), ALLOCATABLE, SAVE :: Axes(:) LOGICAL :: module_is_initialized = .FALSE. CONTAINS ! ! ! Initialize the axis, and return the axis ID. ! ! ! ! diag_axis_init initializes an axis and returns the axis ID that ! is to be used with register_diag_field. This function also ! increments the axis counter and fills in the axes ! ! Short name for axis ! Array of coordinate values ! Units for the axis ! ! Cartesian axis ("X", "Y", "Z", "T") ! ! ! Indicates the direction of the axis: !

Up if +1
Down if -1
Neither up or down if 0

! ! ! Long name for the axis. ! ! ! Axis ID for the previously defined "edges axis" ! ! ! ! ! Auxiliary name, can only be geolon_t or geolat_t ! ! INTEGER FUNCTION diag_axis_init(name, DATA, units, cart_name, long_name, direction,& & set_name, edges, Domain, Domain2, aux, tile_count) CHARACTER(len=*), INTENT(in) :: name REAL, DIMENSION(:), INTENT(in) :: DATA CHARACTER(len=*), INTENT(in) :: units CHARACTER(len=*), INTENT(in) :: cart_name CHARACTER(len=*), INTENT(in), OPTIONAL :: long_name, set_name INTEGER, INTENT(in), OPTIONAL :: direction, edges TYPE(domain1d), INTENT(in), OPTIONAL :: Domain TYPE(domain2d), INTENT(in), OPTIONAL :: Domain2 CHARACTER(len=*), INTENT(in), OPTIONAL :: aux INTEGER, INTENT(in), OPTIONAL :: tile_count TYPE(domain1d) :: domain_x, domain_y INTEGER :: ierr, axlen INTEGER :: i, set, tile INTEGER :: isc, iec, isg, ieg CHARACTER(len=128) :: emsg IF ( .NOT.module_is_initialized ) THEN CALL write_version_number( version, tagname ) ENDIF IF ( PRESENT(tile_count)) THEN tile = tile_count ELSE tile = 1 END IF ! Allocate the axes IF (.NOT. ALLOCATED(Axis_sets)) ALLOCATE(Axis_sets(max_num_axis_sets)) IF (.NOT. ALLOCATED(Axes)) ALLOCATE(Axes(max_axes)) IF (.NOT. ALLOCATED(num_subaxes)) THEN ALLOCATE(num_subaxes(max_axes)) num_subaxes = 0 END IF !---- is there an axis set? ---- IF ( PRESENT(set_name) ) THEN set = get_axis_set_num (set_name) !---- add new set name ---- IF (set == 0) THEN num_axis_sets = num_axis_sets + 1 IF ( num_axis_sets > max_num_axis_sets ) THEN WRITE (emsg, FMT='("num_axis_sets (",I2,") exceeds max_num_axis_sets (",I2,"). ")')& & num_axis_sets, max_num_axis_sets ! ! num_axis_sets () exceeds max_num_axis_sets(). ! Increase max_num_axis_sets via diag_manager_nml. ! CALL error_mesg('diag_axis_mod::diag_axis_init',& & TRIM(emsg)//' Increase max_num_axis_sets via diag_manager_nml.', FATAL) END IF set = num_axis_sets Axis_sets(set) = set_name END IF ELSE set = 0 END IF !---- see if axis already exists -- ! if this is time axis, return the ID of a previously defined ! if this is spatial axis, FATAL error DO i = 1, num_def_axes IF ( TRIM(name) == Axes(i)%name ) THEN IF ( TRIM(name) == 'Stations' .OR. TRIM(name) == 'Levels') THEN diag_axis_init = i RETURN ELSE IF ( set == Axes(i)%set ) THEN IF ( TRIM(lowercase(name)) == 'time' .OR.& & TRIM(lowercase(cart_name)) == 't' .OR.& & TRIM(lowercase(name)) == 'nv' .OR.& & TRIM(lowercase(cart_name)) == 'n' ) THEN diag_axis_init = i RETURN ELSE IF ( (lowercase(cart_name) /= 'x' .AND. lowercase(cart_name) /= 'y')& & .OR. tile /= Axes(i)%tile_count) THEN ! axis_name and axis_set already exist. CALL error_mesg('diag_axis_mod::diag_axis_init',& & 'axis_name '//TRIM(name)//' and axis_set already exist.', FATAL) END IF END IF END IF END DO !---- register axis ---- num_def_axes = num_def_axes + 1 ! max_axes exceeded, increase it via diag_manager_nml IF (num_def_axes > max_axes) CALL error_mesg ('diag_axis_mod::diag_axis_init',& & 'max_axes exceeded, increase via diag_manager_nml', FATAL) diag_axis_init = num_def_axes !---- check and then save cart_name name ---- IF ( TRIM(uppercase(cart_name)) == 'X' .OR.& & TRIM(uppercase(cart_name)) == 'Y' .OR.& & TRIM(uppercase(cart_name)) == 'Z' .OR.& & TRIM(uppercase(cart_name)) == 'T' .OR.& & TRIM(uppercase(cart_name)) == 'N' ) THEN Axes(diag_axis_init)%cart_name = TRIM(uppercase(cart_name)) ELSE ! Invalid cart_name name. CALL error_mesg('diag_axis_mod::diag_axis_init', 'Invalid cart_name name.', FATAL) END IF !---- allocate storage for coordinate values of axis ---- IF ( Axes(diag_axis_init)%cart_name == 'T' ) THEN axlen = 0 ELSE axlen = SIZE(DATA(:)) END IF ALLOCATE ( Axes(diag_axis_init)%data(1:axlen) ) ! Initialize Axes(diag_axis_init) Axes(diag_axis_init)%name = TRIM(name) Axes(diag_axis_init)%data = DATA(1:axlen) Axes(diag_axis_init)%units = units Axes(diag_axis_init)%length = axlen Axes(diag_axis_init)%set = set ! start and end are used in subaxes information only Axes(diag_axis_init)%start = -1 Axes(diag_axis_init)%end = -1 Axes(diag_axis_init)%subaxis_name = "" Axes(diag_axis_init)%shift = 0 IF ( PRESENT(long_name) ) THEN Axes(diag_axis_init)%long_name = long_name ELSE Axes(diag_axis_init)%long_name = name END IF IF ( PRESENT(aux) ) THEN Axes(diag_axis_init)%aux = TRIM(aux) ELSE Axes(diag_axis_init)%aux = 'none' END IF !---- axis direction (-1, 0, or +1) ---- IF ( PRESENT(direction) )THEN IF ( ABS(direction) /= 1 .AND. direction /= 0 )& ! direction must be 0, +1, or -1 & CALL error_mesg('diag_axis_mod::diag_axis_init', 'direction must be 0, +1 or -1', FATAL) Axes(diag_axis_init)%direction = direction ELSE Axes(diag_axis_init)%direction = 0 END IF !---- domain2d type ---- IF ( PRESENT(Domain2) .AND. PRESENT(Domain)) THEN ! Presence of both Domain and Domain2 at the same time is prohibited CALL error_mesg('diag_axis_mod::diag_axis_init',& & 'Presence of both Domain and Domain2 at the same time is prohibited', FATAL) ELSE IF ( PRESENT(Domain2) .OR. PRESENT(Domain)) THEN IF ( Axes(diag_axis_init)%cart_name /= 'X' .AND. Axes(diag_axis_init)%cart_name /= 'Y') THEN ! Domain must not be present for an axis which is not in the X or Y direction. CALL error_mesg('diag_axis_mod::diag_axis_init',& & 'Domain must not be present for an axis which is not in the X or Y direction', FATAL) END IF END IF Axes(diag_axis_init)%tile_count = tile IF ( PRESENT(Domain2) ) THEN Axes(diag_axis_init)%Domain2 = Domain2 CALL mpp_get_domain_components(Domain2, domain_x, domain_y, tile_count=tile_count) IF ( Axes(diag_axis_init)%cart_name == 'X' ) Axes(diag_axis_init)%Domain = domain_x IF ( Axes(diag_axis_init)%cart_name == 'Y' ) Axes(diag_axis_init)%Domain = domain_y ELSE IF ( PRESENT(Domain)) THEN !---- domain1d type ---- Axes(diag_axis_init)%Domain2 = null_domain2d ! needed since not 2-D domain Axes(diag_axis_init)%Domain = Domain ELSE Axes(diag_axis_init)%Domain2 = null_domain2d Axes(diag_axis_init)%Domain = null_domain1d END IF !--- set up the shift value for x-y axis IF ( Axes(diag_axis_init)%Domain .NE. null_domain1d ) THEN CALL mpp_get_compute_domain(Axes(diag_axis_init)%Domain, isc, iec) CALL mpp_get_global_domain(Axes(diag_axis_init)%Domain, isg, ieg) IF ( Axes(diag_axis_init)%length == ieg - isg + 2 ) THEN Axes(diag_axis_init)%shift = 1 END IF END IF !---- have axis edges been defined ? ---- Axes(diag_axis_init)%edges = 0 IF (PRESENT(edges) ) THEN IF ( edges > 0 .AND. edges < num_def_axes ) THEN ierr=0 IF ( Axes(edges)%cart_name /= Axes(diag_axis_init)%cart_name) ierr=1 IF ( Axes(edges)%length /= Axes(diag_axis_init)%length+1 ) ierr=ierr+2 IF ( Axes(edges)%set /= Axes(diag_axis_init)%set ) ierr=ierr+4 IF ( ierr > 0 ) THEN ! Edges axis does not match axis (code ).


             WRITE (emsg,'("Edges axis does not match axis (code ",I1,").")') ierr
             CALL error_mesg('diag_axis_mod::diag_axis_init', emsg, FATAL)
          END IF
          Axes(diag_axis_init)%edges = edges
       ELSE
          ! Edges axis is not defined.
          CALL error_mesg('diag_axis_mod::diag_axis_init', 'Edges axis is not defined', FATAL)
       END IF
    END IF

    ! Module is now initialized
    module_is_initialized = .TRUE.

  END FUNCTION diag_axis_init
  !



  ! 
  !   
  !     Create a subaxis on a parent axis.
  !   
  !   
  !   
  !     Given the ID of a parent axis, create a subaxis and fill it with data,
  !     and return the ID of the corresponding subaxis.
  !
  !     The subaxis is defined on the parent axis from start_indx
  !     to end_indx.
  !   
  !   ID of the parent axis
  !   Data of the subaxis
  !   Start index of the subaxis
  !   End index of the subaxis
  !   
  !   
  INTEGER FUNCTION diag_subaxes_init(axis, subdata, start_indx, end_indx, domain_2d)
    INTEGER, INTENT(in) :: axis
    REAL, DIMENSION(:), INTENT(in) :: subdata
    INTEGER, INTENT(in) :: start_indx
    INTEGER, INTENT(in) :: end_indx
    TYPE(domain2d), INTENT(in), OPTIONAL  :: domain_2d

    INTEGER :: i, nsub_axis, direction
    INTEGER :: xbegin, xend, ybegin, yend
    INTEGER :: ad_xbegin, ad_xend, ad_ybegin, ad_yend
    CHARACTER(len=128) :: name, nsub_name
    CHARACTER(len=128) :: units
    CHARACTER(len=128) :: cart_name
    CHARACTER(len=128) :: long_name
    CHARACTER(len=128) :: emsg
    LOGICAL :: subaxis_set, hasDomain

    ! there may be more than 1 subaxis on a parent axis, check for redundancy
    nsub_axis = 0
    subaxis_set = .FALSE.

    IF ( PRESENT(domain_2d) ) THEN
       hasDomain = .TRUE.
       CALL mpp_get_compute_domain(domain_2d, xbegin, xend, ybegin, yend)
    ELSE
       hasDomain = .FALSE.
    END IF
    sa_search: DO i = 1, num_subaxes(axis)
       IF ( start_indx == Axes(axis)%start(i) .AND. end_indx == Axes(axis)%end(i) ) THEN
          IF ( hasDomain ) THEN
             CALL mpp_get_compute_domain(Axes(axis)%subaxis_domain2(i), ad_xbegin, ad_xend, ad_ybegin, ad_yend)
             IF ( .NOT.((xbegin == ad_xbegin .AND. xend == ad_xend) .AND.&
                  & (ybegin == ad_ybegin .AND. yend == ad_yend)) ) THEN
                CYCLE sa_search
             END IF
          END IF
          nsub_axis = i
          subaxis_set = .TRUE.    !subaxis already exists
          name = TRIM(Axes(axis)%subaxis_name(nsub_axis))
          EXIT sa_search
       END IF
    END DO sa_search

    IF ( nsub_axis == 0 ) THEN  ! create new subaxis
       num_subaxes(axis) = num_subaxes(axis) + 1
       IF (num_subaxes(axis) > max_subaxes) THEN
          ! max_subaxes (value ) is too small.  Consider increasing max_subaxes.
          WRITE (emsg,'("max_subaxes (value ",I4,") is too small.  Consider increasing max_subaxes.")') max_subaxes
          CALL error_mesg('diag_axis_mod::diag_subaxes_init', emsg, FATAL)
       END IF
       nsub_axis = num_subaxes(axis)
       Axes(axis)%start(nsub_axis) = start_indx
       Axes(axis)%end(nsub_axis)   = end_indx
       if ( hasDomain ) Axes(axis)%subaxis_domain2(nsub_axis) = domain_2d
    END IF

    ! Create new name for the subaxis from name of parent axis
    ! If subaxis already exists, get the index and return
    IF(subaxis_set) THEN
       IF ( Axes(axis)%set > 0 ) THEN
          diag_subaxes_init = get_axis_num(name, set_name=TRIM(Axis_sets(Axes(axis)%set)))
       ELSE
          diag_subaxes_init = get_axis_num(name)
       END IF
    ELSE
       ! get a new index for subaxis
       !::sdu:: Need a check to allow larger numbers in the index number.
       WRITE (nsub_name,'(I2.2)') nsub_axis
       name = TRIM(Axes(axis)%name)//'_sub'//TRIM(nsub_name)
       Axes(axis)%subaxis_name(nsub_axis) = name
       long_name = TRIM(Axes(axis)%long_name)
       units = TRIM(Axes(axis)%units)
       cart_name = TRIM(Axes(axis)%cart_name)
       direction = Axes(axis)%direction
       IF (Axes(axis)%set > 0) THEN
          diag_subaxes_init =  diag_axis_init (TRIM(name), subdata, TRIM(units), TRIM(cart_name), TRIM(long_name),&
               & set_name=TRIM(Axis_sets(Axes(axis)%set)), direction=direction, Domain2=domain_2d)
       ELSE
          diag_subaxes_init =  diag_axis_init (TRIM(name), subdata, TRIM(units), TRIM(cart_name), TRIM(long_name),&
               & direction=direction, Domain2=domain_2d)
       END IF
    END IF
  END FUNCTION diag_subaxes_init
  ! 

  ! 
  !   
  !     Return information about the axis with index ID
  !   
  !   
  !   
  !     Return information about the axis with index ID
  !   
  !   Axis ID
  !   Short name for axis
  !   Units for axis
  !   Long name for axis
  !   
  !     Cartesian axis ("x", "y", "z", "t").
  !   
  !   
  !     Direction of data. (See diag_axis_init for a description of
  !     allowed values)
  !   
  !   
  !     Axis ID for the previously defined "edges axis".
  !   
  !   
  !   
  !     Array of coordinate values for this axis.
  !   
  SUBROUTINE get_diag_axis(id, name, units, long_name, cart_name,&
       & direction, edges, Domain, DATA)
    CHARACTER(len=*), INTENT(out) :: name, units, long_name, cart_name
    INTEGER, INTENT(in) :: id
    TYPE(domain1d), INTENT(out) :: Domain
    INTEGER, INTENT(out) :: direction, edges
    REAL, DIMENSION(:), INTENT(out) :: DATA

    CALL valid_id_check(id, 'get_diag_axis')
    name      = Axes(id)%name
    units     = Axes(id)%units
    long_name = Axes(id)%long_name
    cart_name = Axes(id)%cart_name
    direction = Axes(id)%direction
    edges     = Axes(id)%edges
    Domain    = Axes(id)%Domain
    IF ( Axes(id)%length > SIZE(DATA(:)) ) THEN
       ! array data is too small.
       CALL error_mesg('diag_axis_mod::get_diag_axis', 'array data is too small', FATAL)
    ELSE
       DATA(1:Axes(id)%length) = Axes(id)%data(1:Axes(id)%length)
    END IF
  END SUBROUTINE get_diag_axis
  ! 

  ! 
  !   
  !     Return the axis cartesian.
  !   
  !   
  !   
  !     Return the axis cartesian ('X', 'Y', 'Z' or 'T') for the axis ID given.
  !   
  !   Axis ID
  !   Cartesian axis
  SUBROUTINE get_diag_axis_cart(id, cart_name)
    INTEGER, INTENT(in)           :: id
    CHARACTER(len=*), INTENT(out) :: cart_name

    CALL valid_id_check(id, 'get_diag_axis_cart')
    cart_name = Axes(id)%cart_name
  END SUBROUTINE get_diag_axis_cart
  ! 

  ! 
  !   
  !     Return the axis data.
  !   
  !   
  !   
  !     Return the axis data for the axis ID given.
  !   
  !   Axis ID
  !   Axis data
  SUBROUTINE get_diag_axis_data(id, DATA)
    INTEGER, INTENT(in) :: id
    REAL, DIMENSION(:), INTENT(out) :: DATA

    CALL valid_id_check(id, 'get_diag_axis_data')
    IF (Axes(id)%length > SIZE(DATA(:))) THEN
       ! array data is too small
       CALL error_mesg('diag_axis_mod::get_diag_axis_data', 'array data is too small', FATAL)
    ELSE
       DATA(1:Axes(id)%length) = Axes(id)%data
    END IF
  END SUBROUTINE get_diag_axis_data
  ! 

  ! 
  !   
  !     Return the short name of the axis.
  !   
  !   
  !   
  !     Return the short name for the axis ID given.
  !   
  !   Axis ID
  !   Axis short name
  SUBROUTINE get_diag_axis_name(id, name)
    INTEGER         , INTENT(in)  :: id
    CHARACTER(len=*), INTENT(out) :: name

    CALL valid_id_check(id, 'get_diag_axis_name')
    name = Axes(id)%name
  END SUBROUTINE get_diag_axis_name
  ! 

  ! 
  !   
  !     Return the name of the axis' domain
  !   
  !   
  !   
  !     Retruns the name of the axis' domain.
  !   
  !   Axis ID
  !   Axis' domain name
  SUBROUTINE get_diag_axis_domain_name(id, name)
    INTEGER, INTENT(in) :: id
    CHARACTER(len=*), INTENT(out) :: name

    CALL valid_id_check(id, 'get_diag_axis_domain_name')
    name = mpp_get_domain_name(Axes(id)%domain2)
  END SUBROUTINE get_diag_axis_domain_name
  ! 

  ! 
  !   
  !     Return the length of the axis.
  !   
  !   
  !   
  !     Return the length of the axis ID given.
  !   
  !   Axis ID
  INTEGER FUNCTION get_axis_length(id)
    INTEGER, INTENT(in) :: id

    INTEGER :: length

    CALL valid_id_check(id, 'get_axis_length')
    IF ( Axes(id)%Domain .NE. null_domain1d ) THEN
       CALL mpp_get_compute_domain(Axes(id)%Domain,size=length)
       !---one extra point is needed for some case. ( like symmetry domain )
       get_axis_length = length + Axes(id)%shift
    ELSE
       get_axis_length = Axes(id)%length
    END IF
  END FUNCTION get_axis_length
  ! 

  ! 
  !   
  !     Return the auxiliary name for the axis.
  !   
  !   
  !   
  !     Returns the auxiliary name for the axis.  The only possible values for
  !     the auxiliary names is geolon_t or geolat_t.
  !   
  !   Axis ID
  CHARACTER(len=138) FUNCTION get_axis_aux(id)
    INTEGER, INTENT(in) :: id

    CALL valid_id_check(id, 'get_axis_aux')
    get_axis_aux =  Axes(id)%aux
  END FUNCTION get_axis_aux
  ! 

  ! 
  !   
  !     Return the global length of the axis.
  !   
  !   
  !   
  !     Returns the global length of the axis ID given.
  !   
  !   Axis ID
  INTEGER FUNCTION get_axis_global_length(id)
    INTEGER, INTENT(in) :: id

    CALL valid_id_check(id, 'get_axis_global_length')
    get_axis_global_length = Axes(id)%length
  END FUNCTION get_axis_global_length
  ! 

  ! 
  !   
  !     Return the tile count for the axis.
  !   
  !   
  !   
  !     Return the tile count for the axis IDs given.
  !   
  !   
  !     Axis IDs.  Possible dimensions: 1 <= size(ids(:)) <= 4.
  !   
  INTEGER FUNCTION get_tile_count(ids)
    INTEGER, DIMENSION(:), INTENT(in) :: ids

    INTEGER :: i, id, flag

    IF ( SIZE(ids(:)) < 1 ) THEN
       ! input argument has incorrect size.
       CALL error_mesg('diag_axis_mod::get_tile_count', 'input argument has incorrect size', FATAL)
    END IF
    get_tile_count = 1
    flag = 0
    DO i = 1, SIZE(ids(:))
       id = ids(i)
       CALL valid_id_check(id, 'get_tile_count')
       IF ( Axes(id)%cart_name == 'X' .OR.  &
            Axes(id)%cart_name == 'Y' ) flag = flag + 1
       !     --- both x/y axes found ---
       IF ( flag == 2 ) THEN
          get_tile_count = Axes(id)%tile_count
          EXIT
       END IF
    END DO
  END FUNCTION get_tile_count
  ! 

  ! 
  !   
  !     Return the 1D domain.
  !   
  !   
  !   
  !     Retrun the 1D domain for the axis ID given.
  !   
  !   Axis ID
  TYPE(domain1d) FUNCTION get_domain1d(id)
    INTEGER, INTENT(in) :: id

    CALL valid_id_check(id, 'get_domain1d')
    IF (Axes(id)%Domain .NE. NULL_DOMAIN1D) THEN
       get_domain1d = Axes(id)%Domain
    ELSE
       get_domain1d = NULL_DOMAIN1D
    ENDIF
  END FUNCTION get_domain1d
  ! 

  ! 
  !   
  !     Return the 2D domain.
  !   
  !   
  !   
  !     Return the 2D domain for the axis IDs given.
  !   
  !   
  !     Axis IDs.  Possible dimensions: 1 <= size(ids(:)) <= 4.
  !   
  TYPE(domain2d) FUNCTION get_domain2d(ids)
    INTEGER, DIMENSION(:), INTENT(in) :: ids

    INTEGER :: i, id, flag

    IF ( SIZE(ids(:)) < 1 ) THEN
       ! input argument has incorrect size.
       CALL error_mesg('diag_axis_mod::get_domain2d', 'input argument has incorrect size', FATAL)
    END IF
    get_domain2d = null_domain2d
    flag = 0
    DO i = 1, SIZE(ids(:))
       id = ids(i)
       CALL valid_id_check(id, 'get_domain2d')
       IF ( Axes(id)%cart_name == 'X' .OR. Axes(id)%cart_name == 'Y' ) flag = flag + 1
       !     --- both x/y axes found ---
       IF ( flag == 2 ) THEN
          IF (Axes(id)%Domain2 .NE. NULL_DOMAIN2D) get_domain2d = Axes(id)%Domain2
          EXIT
       END IF
    END DO
  END FUNCTION get_domain2d
  ! 

  ! 
  !   
  !     Return the value of the shift.
  !   
  !   
  !   
  !     Return the value of the shift for the axis IDs given.
  !   
  !   
  !     Axis IDs.  Possible dimensions: 1 <= size(ids(:)) <= 4
  !   
  !   X shift value.
  !   Y shift value.
  SUBROUTINE get_axes_shift(ids, ishift, jshift)
    INTEGER, DIMENSION(:), INTENT(in) :: ids
    INTEGER, INTENT(out) :: ishift, jshift

    INTEGER :: i, id

    !-- get the value of the shift.
    ishift = 0
    jshift = 0
    DO i = 1, SIZE(ids(:))
       id = ids(i)
       CALL valid_id_check(id, 'get_axes_shift')
       SELECT CASE (Axes(id)%cart_name)
       CASE ( 'X' )
          ishift = Axes(id)%shift
       CASE ( 'Y' )
          jshift = Axes(id)%shift
       END SELECT
    END DO
  END SUBROUTINE get_axes_shift
  ! 

  ! 
  ! 
  !   
  !     Returns index into axis table corresponding to a given axis name.
  !   
  !   
  !   
  !     Returns index into axis table corresponding to a given axis name.
  !   
  !   Axis name.
  !   Set name.
  INTEGER FUNCTION get_axis_num(axis_name, set_name)
    CHARACTER(len=*), INTENT(in) :: axis_name
    CHARACTER(len=*), INTENT(in), OPTIONAL :: set_name

    INTEGER :: set, n

    IF ( PRESENT(set_name) ) THEN
       set = get_axis_set_num (TRIM(set_name))
    ELSE
       set = 0
    END IF
    get_axis_num = 0
    DO n = 1, num_def_axes
       IF ( TRIM(axis_name) == TRIM(Axes(n)%name) .AND. Axes(n)%set == set ) THEN
          get_axis_num = n
          RETURN
       END IF
    END DO
  END FUNCTION get_axis_num
  ! 
  ! 

  ! 
  ! 
  !   
  !     Returns index in axis set table corresponding to a given axis set name.
  !   
  !   
  !   
  !     Returns index in axis set table corresponding to a given axis set name.
  !   
  !   Set name.
  INTEGER FUNCTION get_axis_set_num (set_name)
    CHARACTER(len=*), INTENT(in) :: set_name

    INTEGER :: iset

    get_axis_set_num = 0
    DO iset = 1, num_axis_sets
       IF ( set_name == Axis_sets(iset) ) THEN
          get_axis_set_num = iset
          RETURN
       END IF
    END DO
  END FUNCTION get_axis_set_num
  ! 
  ! 

  ! 
  ! 
  !   
  !     Check to see if the axis id is a vaild id.
  !   
  !   
  !   
  !     Check to see if the given axis id is a valid id.  If the axis id is invalid,
  !     call a FATAL error.  If the ID is valid, just return.
  !   
  !   Axis id to check for validity
  !   Name of the subroutine checking for a valid axis id.
  SUBROUTINE valid_id_check(id, routine_name)
    INTEGER, INTENT(in) :: id
    CHARACTER(len=*), INTENT(in) :: routine_name

    CHARACTER(len=5) :: emsg

    IF ( id < 1 .OR. id > num_def_axes) THEN
       ! 
       !   Illegal value for axis used (value ).
       ! 
       WRITE (emsg, '(I2)') id
       CALL error_mesg('diag_axis_mod::'//TRIM(routine_name),&
            & 'Illegal value for axis_id used (value '//TRIM(emsg)//').', FATAL)
    END IF
  END SUBROUTINE valid_id_check
  ! 
  ! 
END MODULE diag_axis_mod