program read_srb_rel3_qclw_3hrlymonthly_nc
use netcdf
implicit none

character (200) :: path_in, file_in, file_out
integer :: rec
integer :: month, year

character(4) :: cyear
character(2) :: cmon

! netCDF id
integer :: ncid
! dimension ids
integer :: lat_dim, lon_dim, time_dim

integer, parameter :: NDIMS = 3, NRECS = 8
integer, parameter :: NLVLS = 1, NLATS = 180, NLONS = 360
character (len = *), parameter :: LAT_NAME = "lat"
character (len = *), parameter :: LON_NAME = "lon"
character (len = *), parameter :: time_name = "time"

! The start and count arrays will tell the netCDF library where to
! read our data.
integer :: start(NDIMS), count(NDIMS)

! In addition to the latitude and longitude dimensions, we will also
! create latitude and longitude variables which will hold the actual
! latitudes and longitudes. Since they hold data about the
! coordinate system, the netCDF term for these is: "coordinate
! variables."

real :: lats(NLATS), lons(NLONS)

character (len = *), parameter :: sfcdn_name="lw_sfc_dn"
character (len = *), parameter :: sfcnet_name="lw_sfc_net"
character (len = *), parameter :: csfcdn_name="clr_lw_sfc_dn"

! variable ids
integer :: lat_id,  lon_id,  time_id, &
           clr_lw_sfc_dn_id, lw_sfc_net_id, lw_sfc_dn_id

double precision :: time

real, dimension(nlons,nlats) :: clr_lw_sfc_dn,  lw_sfc_net, lw_sfc_dn

integer :: dimids(NDIMS)

! To check the units attributes.
character (80) :: clr_lw_sfc_dn_units_in,  &
           lw_sfc_net_units_in, lw_sfc_dn_units_in
character (80) :: lat_units_in, lon_units_in

month=2
year=1984
write (cyear,"(i4)") year
write (cmon,"(i2.2)") month

path_in=''
path_in='/SCF2/RADAPP/srb/NetCDF/QCLW/1984/'
file_in=trim(path_in)//'srb_rel3.0_qclw_3hrlymonthly_'//cyear//cmon//'.nc'
print*,trim(file_in)

! Open the file.
call check( nf90_open(file_in, nf90_nowrite, ncid))

! Get the varids of the latitude and longitude coordinate variables.
call check( nf90_inq_varid(ncid, LAT_NAME, lat_id) )
call check( nf90_inq_varid(ncid, LON_NAME, lon_id) )

! Read the latitude and longitude data.
call check( nf90_get_var(ncid, lat_id, lats) )
call check( nf90_get_var(ncid, lon_id, lons) )

! Read the time information.
call check( nf90_inq_varid(ncid, time_name, time_id) )
call check( nf90_get_var(ncid, time_id, time) )

! Get the varids of the variables
call check( nf90_inq_varid(ncid, csfcdn_name, clr_lw_sfc_dn_id) )
call check( nf90_inq_varid(ncid, sfcnet_name, lw_sfc_net_id) )
call check( nf90_inq_varid(ncid, sfcdn_name, lw_sfc_dn_id) )

! Read the units
call check( nf90_get_att(ncid, clr_lw_sfc_dn_id, 'units', clr_lw_sfc_dn_units_in) )
call check( nf90_get_att(ncid, lw_sfc_net_id, 'units', lw_sfc_net_units_in) )
call check( nf90_get_att(ncid, lw_sfc_dn_id, 'units', lw_sfc_dn_units_in) )

count = (/ NLONS, NLATS, 1 /)
start = (/ 1, 1, 1 /)

do rec = 1, NRECS
   start(3)=rec
! Read the variables
   call check( nf90_get_var(ncid, clr_lw_sfc_dn_id, clr_lw_sfc_dn,start=start,&
       count=count) )
   call check( nf90_get_var(ncid, lw_sfc_net_id, lw_sfc_net,start=start,&
       count=count) )
   call check( nf90_get_var(ncid, lw_sfc_dn_id, lw_sfc_dn,start=start,&
       count=count) )
end do
call check( nf90_close(ncid) )


contains
!*****************************************
  subroutine check(status)
    integer, intent ( in) :: status

    if(status /= nf90_noerr) then
      print *, trim(nf90_strerror(status))
      stop "Stopped"
    end if
  end subroutine check
!*****************************************

end program read_srb_rel3_qclw_3hrlymonthly_nc