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Xueming Zhu, > Thanks for your replying. But if in that case, I have a question why > I can not find any introduction of the nf90_put_vara from your link or > the help file of netcdf interface( attached by this e-mail)? I just can > find the interface nf90_put_var, and it looks like can be used to wroten > an array to the netcdf variable. I know that there are an interface > nf_put_vara for nf77. But never heard about the nf90_put_vara. Oops, sorry, I forgot that the nf90_put_var interface already includes the put_vara behavior if you provide the optional keyword arguments "start=..." and "count=...". You're right, that there is no separate function for using those optional arguments, as there is in C, which didn't have optional keyword arguments. A Fortran-90 example using those arguments to write a record variable is here: http://www.unidata.ucar.edu/software/netcdf/examples/programs/pres_temp_4D_wr.f90 --Russ > 2013/8/23 0:34, Unidata netCDF Support ?: > > Hi Xueming Zhu, > > > >> I tried to write data to an exist netCDF file with record variables > >> on cygwin platform. My fortran codes as follow, > >> > >> clm =trim(direc)//trim(casename)//'_monthly_'//year//'.nc' > >> ierr=nf90_open(trim(clm),nf90_write,ncid) > >> CALL HANDLE_ERR(ierr) > >> do m=1,12 > >> ierr=nf90_inq_varid(ncid,'ocean_time',varid) > >> CALL HANDLE_ERR(ierr) > >> ierr=nf90_put_var(ncid,varid,dnum,start=(/ m /)) > >> CALL HANDLE_ERR(ierr) > >> enddo > >> > >> the variable ocean_time's dimension is ocean_time, which is an > >> unlimited dimension. At beginning, ocean_time's dimension is 1. But > >> after the loop, it is 1 still. Some ncdump results as follow, > >> > >> $ ncdump.exe -v ocean_time np8_monthly_2002.nc > >> netcdf np8_monthly_2002 { > >> dimensions: > >> tracer = 2 ; > >> boundary = 4 ; > >> s_rho = 22 ; > >> s_w = 23 ; > >> ocean_time = UNLIMITED ; // (1 currently) > >> eta_rho = 633 ; > >> xi_rho = 1545 ; > >> eta_u = 633 ; > >> xi_u = 1544 ; > >> eta_v = 632 ; > >> xi_v = 1545 ; > >> variables: > >> > >> double ocean_time(ocean_time) ; > >> ocean_time:long_name = "averaged time since > >> initialization" ; > >> ocean_time:units = "seconds since 1990-01-01 00:00:00" ; > >> ocean_time:calendar = "gregorian" ; > >> ocean_time:field = "time, scalar, series" ; > >> > >> I found the file size changed, but had not got any error when run the > >> fortran code. It is weird for me. > >> > >> Can you give me any suggestions to fix the problem? Thanks a lot. > > I think the problem is that you should be using nf90_put_vara > > instead of nf90_put_var. For an explanation why, see this section > > of the nf90_put_var documentation: > > > > > > http://www.unidata.ucar.edu/netcdf/docs/netcdf-f90.html#NF90_005fPUT_005fVAR > > > > where it says: > > > > Take care when using the simplest forms of this interface with > > record variables (variables that use the NF90_UNLIMITED dimension) > > when you don't specify how many records are to be written. If you > > try to write all the values of a record variable into a netCDF file > > that has no record data yet (hence has 0 records), nothing will be > > written. Similarly, if you try to write all the values of a record > > variable from an array but there are more records in the file than > > you assume, more in-memory data will be accessed than you expect, > > which may cause a segmentation violation. To avoid such problems, it > > is better to specify start and count arguments for variables that > > use the NF90_UNLIMITED dimension. > > > > --Russ > > > > Russ Rew UCAR Unidata Program > > address@hidden http://www.unidata.ucar.edu > > > > > > > > Ticket Details > > =================== > > Ticket ID: ZMF-465105 > > Department: Support netCDF > > Priority: Normal > > Status: Closed > > > > > > > Russ Rew UCAR Unidata Program address@hidden http://www.unidata.ucar.edu Ticket Details =================== Ticket ID: ZMF-465105 Department: Support netCDF Priority: Normal Status: Closed