unlimited_sds.f

      program append_sds

      implicit none

C

C     Parameter declaration.

C

      character*16  FILE_NAME

      character*14  SDS_NAME

      integer       X_LENGTH, Y_LENGTH, RANK

      parameter    (FILE_NAME = 'SDSUNLIMITED.hdf',

     +              SDS_NAME = 'AppendableData',

     +              X_LENGTH = 10, 

     +              Y_LENGTH = 10,

     +              RANK     = 2)

      integer       DFACC_CREATE, DFACC_WRITE, SD_UNLIMITED,

     +              DFNT_INT32

      parameter    (DFACC_CREATE = 4,

     +              DFACC_WRITE  = 2,

     +              SD_UNLIMITED = 0,

     +              DFNT_INT32 =   24)

C

C     Function declaration.

C

      integer sfstart, sfcreate, sfwdata, sfselect 

      integer sfendacc, sfend

C

C**** Variable declaration *******************************************

C

      integer sd_id, sds_id, sds_index, status

      integer dim_sizes(2)

      integer start(2), edges(2), stride(2)

      integer i, j

      integer data (X_LENGTH, Y_LENGTH), append_data(X_LENGTH)

C

C**** End of variable declaration ************************************

C

C

C     Data initialization.

C 

      do 20 j = 1, Y_LENGTH

         do 10 i = 1, X_LENGTH

            data(i, j) = i + j

10      continue

20    continue

C

C     Create the file and initialize the SD interface. 

C

      sd_id = sfstart(FILE_NAME, DFACC_CREATE)

C

C     Define dimensions of the array. Make the

C     last dimension appendable by defining its length as unlimited.

C

      dim_sizes(1) = X_LENGTH

      dim_sizes(2) = SD_UNLIMITED

C     Create the array data set. 

      sds_id = sfcreate(sd_id, SDS_NAME, DFNT_INT32, RANK, 

     .                  dim_sizes)

C

C     Define the location and the size of the data to be written

C     to the data set. Note that the elements of array stride are

C     set to 1 for contiguous writing.    

C

      start(1) = 0

      start(2) = 0

      edges(1) = X_LENGTH

      edges(2) = Y_LENGTH

      stride(1) = 1

      stride(2) = 1

C

C     Write the data. 

C

      status = sfwdata(sds_id, start, stride, edges, data)

C

C     Terminate access to the data set, terminate access

C     to the SD interface, and close the file. 

C

      status = sfendacc(sds_id)

      status = sfend(sd_id)

C

C     Store the array values to be appended to the data set. 

C

      do 30 i = 1, X_LENGTH

         append_data(i) = 1000 + i - 1 

30    continue

C

C     Reopen the file and initialize the SD. 

C

      sd_id = sfstart(FILE_NAME, DFACC_WRITE)

C

C     Select the first data set. 

C

      sds_index = 0 

      sds_id = sfselect(sd_id, sds_index)

C

C     Define the location of the append to start at the 11th 

C     column of the 1st row and to stop at the end of the 10th row.

C

      start(1) = 0

      start(2) = Y_LENGTH

      edges(1) = X_LENGTH

      edges(2) = 1

C

C     Append the data to the data set. 

C

      status = sfwdata(sds_id, start, stride, edges, append_data)

C

C     Terminate access to the data set. 

C

      status = sfendacc(sds_id)

C

C     Terminate access to the SD interface and close the file. 

C

      status = sfend(sd_id)

      end