I want to use nf90_get_var to read in
double time(sounding_id) ;
time = 1451606399.896, 1451606399.92199, 1451606399.94902, 1451606400.00302,
1451606400.03001, 1451606400.05701, 1451606400.22901, 1451606400.28199,
...
Why do I read all 0 values, no matter which of the following two methods?
call check( nf90_get_var(ncid, varid, time_xhu) )
write(*,*) "finish reading time_xhu ",time_xhu(1:2)
count = (/ 1 /)
start = (/ 1 /)
call check( nf90_get_var(ncid, varid, time_xhu_single,start=start,count =
count) )
write(*,*) "finish reading time_xhu_single ",time_xhu_single
I also attached the full script.
Thanks a lot!
Xiaoming
program process_xco2
! use HDF5
use netcdf
implicit none
! This will be the netCDF ID for the file and data variable.
integer :: ncid, varid
INTEGER(kind=8) :: YYYYMMDDHHMM
INTEGER(kind=8) :: YYYYMMDDHHMMSS
INTEGER(kind=8) :: YYYYMMDDHHMM_pre
INTEGER :: Year, Month, Day, HH, MM, SS
INTEGER :: Year_pre, Month_pre, HH_pre, Day_pre
integer :: i, N_count
integer, parameter :: N_rec = 31866010! change 5->6 won't work
! integer, parameter :: N_rec = 63147832
! integer(kind=8), parameter :: N_rec = 63147832
character(LEN=100) :: OCO_filename
real,dimension(N_rec) :: xco2, lat, lon
real,dimension(N_rec) :: time_xhu
real*8,dimension(1) :: time_xhu_single
real :: XCO2_accumulate,lat_acc, lon_acc
! character(LEN=16), dimension(N_rec) :: date
integer, dimension(N_rec,7) :: date
character(N_rec) :: xco2_quality_flag
! To check the units attributes.
character (len = *), parameter :: UNITS = "units"
integer, parameter :: MAX_ATT_LEN = 80
integer :: att_len
character*(MAX_ATT_LEN) :: time_units_in
integer :: ndims_in, nvars_in, ngatts_in, unlimdimid_in
CHARACTER(LEN=15) ::dname
INTEGER :: dlength
INTEGER :: ii
character(len=15) :: name
integer :: xtype, ndims
integer :: natts
integer :: start(1), count(1)
OCO_filename= "OCO-2_9_LITE_LEVEL2_extracted_2016only.nc"
write(*,*) "will open ",trim(OCO_filename)
call check( nf90_open(trim(OCO_filename), NF90_NOWRITE, ncid) )
call check( nf90_inquire(ncid, ndims_in, nvars_in, ngatts_in,
unlimdimid_in) )
write(*,*)
"ndims_in=",ndims_in,"nvars_in=",nvars_in,"ngatts_in",ngatts_in,"unlimdimid_in=",unlimdimid_in
DO ii=1,ndims_in-1
CALL check(NF90_INQUIRE_DIMENSION(ncid,ii,dname,len=dlength))
SELECT CASE (TRIM(dname))
CASE ('sounding_id')
write(*,*) "dimension ",trim(dname)," is ",dlength
CASE DEFAULT
PRINT*,' Error while reading dimensions....'
PRINT*,' Some dimensions are missing. '
PRINT*,' The program is terminating....';STOP
END SELECT
END DO
! Get the varid of the data variable, based on its name.
call check( nf90_inq_varid(ncid, "time", varid) )
call check( nf90_inquire_variable(ncid, varid, name, xtype, ndims))
call check( nf90_get_var(ncid, varid, time_xhu) )
write(*,*) "finish reading time_xhu ",time_xhu(1:2)
count = (/ 1 /)
start = (/ 1 /)
call check( nf90_get_var(ncid, varid, time_xhu_single,start=start,count =
count) )
write(*,*) "finish reading time_xhu_single ",time_xhu_single
call check( nf90_get_att(ncid, varid, UNITS, time_units_in) )
call check( nf90_inquire_attribute(ncid, varid, UNITS, len = att_len) )
write(*,*) "units=",time_units_in(1:att_len)
call check( nf90_inq_varid(ncid, "xco2", varid) )
call check( nf90_get_var(ncid, varid, xco2) )
write(*,*) "finish reading xco2 ",xco2(1:2)
call check( nf90_inq_varid(ncid, "longitude", varid) )
call check( nf90_get_var(ncid, varid, lon) )
write(*,*) "finish reading lon ",lon(1:2)
call check( nf90_inq_varid(ncid, "latitude", varid) )
call check( nf90_get_var(ncid, varid, lat) )
write(*,*) "finish reading lat ",lat(1:2)
call check( nf90_inq_varid(ncid, "date", varid) )
call check( nf90_get_var(ncid, varid, date) )
! call check( nf90_inq_varid(ncid, "xco2_quality_flag", varid) )
! call check( nf90_get_var(ncid, varid, xco2_quality_flag) )
call check( nf90_close(ncid) )
HH_pre = 0 ! to be consistent
XCO2_accumulate = 0
N_count = 0
! open(88,
File="oco2_LtCO2_China_150101_171231.nc_2sMean.txt",action="write")
! open(88,
File="oco2_LtCO2_China_150101_171231.nc_6sMean.txt",action="write")
open(88,
File="OCO-2_9_LITE_LEVEL2_extracted_2016only.nc_20sMean.txt",action="write")
write(88,'(A20, 3A16)'), "YYYYMMDDHHMM", "accumu_XCO2","lat","lon"
do i = 1, N_rec
! write(*,'(A15)'), date(i)
! write(*,*) xco2_quality_flag(i:i)
read(date(i),*) YYYYMMDDHHMMSS
! YYYYMMDDHHMM = YYYYMMDDHHMMSS/2*2 ! 1second 7km 2s mean
! YYYYMMDDHHMM = YYYYMMDDHHMMSS/100*100+mod(YYYYMMDDHHMMSS,100)/6*6 ! 6s
mean
YYYYMMDDHHMM = YYYYMMDDHHMMSS/100*100+mod(YYYYMMDDHHMMSS,100)/20*20 !
20s mean
! if(xco2_quality_flag(i:i).eq."0") then
if (YYYYMMDDHHMM_pre.ne.YYYYMMDDHHMM.and.I.gt.1) then
XCO2_accumulate = XCO2_accumulate/N_count
lat_acc = lat_acc/N_count
lon_acc = lon_acc/N_count
write(88,'(I20,3F16.6)'),
YYYYMMDDHHMM_pre, XCO2_accumulate, lat_acc, lon_acc
write(*,'(A, I20,F18.6, 2F10.3)'),"!!!!!average!!",
YYYYMMDDHHMM_pre, XCO2_accumulate, lat_acc, lon_acc
XCO2_accumulate = XCO2(i) ! restart calculation
lat_acc = lat(i) ! restart calculation
lon_acc = lon(i) ! restart calculonion
N_count = 1
else
XCO2_accumulate = XCO2_accumulate + XCO2(i)
lat_acc = lat_acc + lat(i)
lon_acc = lon_acc + lon(i)
N_count = N_count + 1
end if
write(*,'(A,1x,A,1x,A,1x, I20,F16.6, 2F10.3,I5)') "flag ",
xco2_quality_flag(i:i), " good!@" &
,YYYYMMDDHHMMSS, XCO2(i) ,lat(i),lon(i), N_count
YYYYMMDDHHMM_pre = YYYYMMDDHHMM
! else
! write(*,*) "with flag ", xco2_quality_flag(i:i), " bad!"
! end if
end do
XCO2_accumulate = XCO2_accumulate/N_count
lat_acc = lat_acc/N_count
lon_acc = lon_acc/N_count
write(88,'(I20,3F16.6)'), YYYYMMDDHHMM_pre,
XCO2_accumulate, lat_acc, lon_acc
write(*,'(A, I20,F18.6, 2F10.3,I5)'),"!!!!!average!!",
YYYYMMDDHHMM_pre, XCO2_accumulate, lat_acc, lon_acc, N_count
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
