c This example shows how to read a data field in HDF-EOS2 grid data.

      program read_datafield_grid_MCD43C4

      implicit none

      integer*4 gridfile1
      integer*4 grid1
      integer status
      integer*4 datafield1rank(32)
      integer*4 datafield1dimsize(32)
      integer*4 datafield1type(1)
      character*512 datafield1dimname
      integer*2 datafield1data(7200,3600)
      integer*4 datafield1start(2)
      integer*4 datafield1stride(2)
      integer*4 datafield1edge(2)
      integer*4 i, j
      integer gdrdfld, gdfldinfo, gddetach, gdclose
      external gdrdfld, gdfldinfo, gddetach, gdclose
      integer*4 gdopen, gdattach
      external gdopen, gdattach
      integer*4 DFACC_READ
      parameter (DFACC_READ=1)

c Open 'MCD43C4.A2000049.005.2006271205532.hdf' using grid API
      gridfile1 = gdopen('MCD43C4.A2000049.005.2006271205532.hdf',
     $  DFACC_READ)

c Open a grid named 'MCD_CMG_BRDF_0.05Deg'
      grid1 = gdattach(gridfile1, 'MCD_CMG_BRDF_0.05Deg')

c Retrieve information about 'Nadir_Reflectance_Band1' datafield
      status = gdfldinfo(grid1, 'Nadir_Reflectance_Band1',
     $  datafield1rank, datafield1dimsize, datafield1type,
     $  datafield1dimname)
c Select necessary range of elements
      datafield1start(1) = 0
      datafield1stride(1) = 1
      datafield1edge(1) = 7200
      datafield1start(2) = 0
      datafield1stride(2) = 1
      datafield1edge(2) = 3600
c Read data from 'Nadir_Reflectance_Band1'
      status = gdrdfld(grid1, 'Nadir_Reflectance_Band1',
     $  datafield1start, datafield1stride, datafield1edge,
     $  datafield1data)
c Dump data from 'Nadir_Reflectance_Band1'
      do i = 1, 36
        do j = 1, 72
          write(*,*), datafield1data(j,i)
        enddo
        write(*,*)
      enddo

c Close the grid named 'MCD_CMG_BRDF_0.05Deg'
      status = gddetach(grid1)

c Close 'MCD43C4.A2000049.005.2006271205532.hdf'
      status = gdclose(gridfile1)

      end