get_attr.f

      program  attr_info

      implicit none

C

C     Parameter declaration.

C

      character*7  FILE_NAME

      character*13 FILE_ATTR_NAME

      character*11 SDS_ATTR_NAME

      character*10 DIM_ATTR_NAME

      parameter   (FILE_NAME = 'SDS.hdf',

     +             FILE_ATTR_NAME = 'File_contents',

     +             SDS_ATTR_NAME  = 'Valid_range',

     +             DIM_ATTR_NAME  = 'Dim_metric')

      integer      DFACC_READ, DFNT_FLOAT32

      parameter   (DFACC_READ   = 1,

     +             DFNT_FLOAT32 = 5)

C

C     Function declaration.

C

      integer sfstart, sffattr, sfgainfo, sfrattr, sfselect

      integer sfdimid, sfendacc, sfend

C

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

C

      integer      sd_id, sds_id, dim_id

      integer      attr_index, data_type, n_values, status

      real         sds_data(2)

      character*20 attr_name 

      character*16 file_data

      character*7  dim_data

      integer      i

C

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

C

C

C     Open the file and initialize SD interface. 

C

      sd_id = sfstart(FILE_NAME, DFACC_READ)

C

C     Find the file attribute defined by FILE_ATTR_NAME.

C     Note that the first parameter is an SD interface identifier.

C

      attr_index = sffattr(sd_id, FILE_ATTR_NAME)

C

C     Get information about the file attribute. 

C

      status = sfgainfo(sd_id, attr_index, attr_name, data_type, 

     +			n_values)

C

C     Read the file attribute data. 

C

      status = sfrattr(sd_id, attr_index, file_data)

C

C     Print file attribute value.

C

      write(*,*) "File attribute value is : ", file_data 

C

C     Select the first data set. 

C

      sds_id = sfselect(sd_id, 0)

C

C     Find the data set attribute defined by SDS_ATTR_NAME.

C     Note that the first parameter is a data set identifier. 

C

      attr_index = sffattr(sds_id, SDS_ATTR_NAME)

C

C     Get information about the data set attribute. 

C

      status = sfgainfo(sds_id, attr_index, attr_name, data_type, 

     +			n_values)

C

C     Read the SDS attribute data. 

C

      status = sfrattr(sds_id, attr_index, sds_data)

C

C     Print SDS attribute data type and values. 

C

      if (data_type .eq. DFNT_FLOAT32)  then

         write(*,*) "SDS attribute data type is : float32 "  

      endif

      write(*,*) "SDS attribute values are  : " 

      write(*,*)  (sds_data(i), i=1, n_values) 

C

C     Get the identifier for the first dimension of the SDS. 

C

      dim_id = sfdimid(sds_id, 0)

C

C     Find the dimensional attribute defined by DIM_ATTR_NAME.

C     Note that the first parameter is a dimension identifier.

C

      attr_index = sffattr(dim_id, DIM_ATTR_NAME)

C

C     Get information about dimension attribute. 

C

      status = sfgainfo(dim_id, attr_index, attr_name, data_type, 

     +			n_values)

C

C     Read the dimension attribute data. 

C

      status = sfrattr(dim_id, attr_index, dim_data)

C

C     Print dimension attribute value.

C

      write(*,*) "Dimensional attribute value is : ", dim_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)

C

C     Output of this program is :

C

C

C     File attribute value is : Storm_track_data

C     SDS attribute data type is : float32 

C     SDS attribute values are  : 

C         2.00000   10.00000

C      Dimensional attribute value is : Seconds

C

      end