find_sds_by_name.f

      program  locate_by_name

      implicit none

C

C     Parameter declaration.

C

      character*7  FILE_NAME

      character*11 SDS_NAME

      character*9  WRONG_NAME

      integer      X_LENGTH, Y_LENGTH

      parameter   (FILE_NAME  = 'SDS.hdf',

     +             SDS_NAME   = 'SDStemplate',

     +             WRONG_NAME = 'WrongName',

     +             X_LENGTH = 5,

     +             Y_LENGTH = 16)

      integer      DFACC_READ, DFNT_INT32

      parameter   (DFACC_READ = 1,

     +             DFNT_INT32 = 24)

C

C     Function declaration.

C

      integer sfstart, sfn2index, sfselect, sfrdata, sfendacc, sfend

C

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

C 

      integer sd_id, sds_id, sds_index, status

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

      integer data(X_LENGTH, Y_LENGTH)

      integer j

C

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

C

C

C     Open the file and initialize the SD interface.

C

      sd_id = sfstart(FILE_NAME, DFACC_READ)

C

C     Find index of the data set with the name specified in WRONG_NAME. 

C     Error condition occurs, since a data set with this name 

C     does not exist in the file.

C

      sds_index = sfn2index(sd_id, WRONG_NAME)

      if (sds_index .eq. -1) then

        write(*,*) "Data set with the name ", WRONG_NAME,

     +             " does not exist"        

      endif

C

C     Find index of the data set with the name specified in SDS_NAME  

C     and use the index to attach to the data set. 

C

      sds_index = sfn2index(sd_id, SDS_NAME)

      sds_id    = sfselect(sd_id, sds_index)

C

C     Set elements of start array to 0, elements of edges array 

C     to SDS dimensions, and elements of stride array to 1 to read entire data. 

C

      start(1) = 0

      start(2) = 0

      edges(1) = X_LENGTH

      edges(2) = Y_LENGTH

      stride(1) = 1

      stride(2) = 1

C

C     Read entire data into array named data. 

C

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

C

C     Print 10th column; the following numbers should be displayed:

C

C           10 1000 12 13 14

C

      write(*,*) (data(j,10), j = 1, X_LENGTH)

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