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Hi Manmeet, I think both the problems you are seeing are due to not telling gfortran where to find the declaration of functions provided by the netCDF-Fortran library. If it doesn't know that the nf90_strerror() returns a character string, then it will assume that the trim() function can't be used on its return value. For gfortran, you need to use the -I option to tell the compiler where to find the necessary compiled Fortran modules, specifying the interface types of all the functions and therri arguments. When you built netCDF-Fortran, it should have installed the nf-config in the bin/ subdirectory of wherever you specified with a --prefix= option to the configure script. By default, this would be /usr/local/bin/nf-config. Use that program to see what flags to use when you compile Fortran programs to use netCDF. Try "nf-config --all" or even use it on the command line, such as gfortran myprogram.f90 -o myprogram `nf-config --fflags --flibs` --Russ nf-config > I am trying to generate a netcdf file from my simulation using the sample > example given on the website > ************************************************************************************************************************************************************************************************** > > This is part of the netCDF package. > ! Copyright 2006 University Corporation for Atmospheric Research/Unidata. > ! See COPYRIGHT file for conditions of use. > > ! This is a very simple example which writes a 2D array of > ! sample data. To handle this in netCDF we create two shared > ! dimensions, "x" and "y", and a netCDF variable, called "data". > > ! This example demonstrates the netCDF Fortran 90 API. This is part > ! of the netCDF tutorial, which can be found at: > ! http://www.unidata.ucar.edu/software/netcdf/docs/netcdf-tutorial > > ! Full documentation of the netCDF Fortran 90 API can be found at: > ! http://www.unidata.ucar.edu/software/netcdf/docs/netcdf-f90 > > ! $Id: simple_xy_wr.f90,v 1.7 2006/12/09 18:44:58 russ Exp $ > > program simple_xy_wr > use netcdf > implicit none > > ! This is the name of the data file we will create. > character (len = *), parameter :: FILE_NAME = "simple_xy.nc" > > ! We are writing 2D data, a 6 x 12 grid. > integer, parameter :: NDIMS = 2 > integer, parameter :: NX = 6, NY = 12 > > ! When we create netCDF files, variables and dimensions, we get back > ! an ID for each one. > integer :: ncid, varid, dimids(NDIMS) > integer :: x_dimid, y_dimid > > ! This is the data array we will write. It will just be filled with > ! a progression of integers for this example. > integer :: data_out(NY, NX) > > ! Loop indexes, and error handling. > integer :: x, y > > ! Create some pretend data. If this wasn't an example program, we > ! would have some real data to write, for example, model output. > do x = 1, NX > do y = 1, NY > data_out(y, x) = (x - 1) * NY + (y - 1) > end do > end do > > ! Always check the return code of every netCDF function call. In > ! this example program, wrapping netCDF calls with "call check()" > ! makes sure that any return which is not equal to nf90_noerr (0) > ! will print a netCDF error message and exit. > > ! Create the netCDF file. The nf90_clobber parameter tells netCDF to > ! overwrite this file, if it already exists. > call check( nf90_create(FILE_NAME, NF90_CLOBBER, ncid) ) > > ! Define the dimensions. NetCDF will hand back an ID for each. > call check( nf90_def_dim(ncid, "x", NX, x_dimid) ) > call check( nf90_def_dim(ncid, "y", NY, y_dimid) ) > > ! The dimids array is used to pass the IDs of the dimensions of > ! the variables. Note that in fortran arrays are stored in > ! column-major format. > dimids = (/ y_dimid, x_dimid /) > > ! Define the variable. The type of the variable in this case is > ! NF90_INT (4-byte integer). > call check( nf90_def_var(ncid, "data", NF90_INT, dimids, varid) ) > > ! End define mode. This tells netCDF we are done defining metadata. > call check( nf90_enddef(ncid) ) > > ! Write the pretend data to the file. Although netCDF supports > ! reading and writing subsets of data, in this case we write all the > ! data in one operation. > call check( nf90_put_var(ncid, varid, data_out) ) > > ! Close the file. This frees up any internal netCDF resources > ! associated with the file, and flushes any buffers. > call check( nf90_close(ncid) ) > > print *, "*** SUCCESS writing example file simple_xy.nc! " > > 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 simple_xy_wr > > ****************************************************************************************************************************************** > > The change I have done is just increase the number of dimensions from > 2 to 3. And the gfortran compiler is not picking up the nf90_create > function somehow I have not been able to figure out. It is giving the > error > > print *, trim(nf90_strerror(status)) > 1 > Error: 'string' argument of 'trim' intrinsic at (1) must be CHARACTER > > I believe this has something to do with the nf90_strerror function. Can you > please help me out with this. > > Thanking You > > Manmeet Singh > Trainee Scientist > Indian Institute of Tropical Meteorology > Pune, India > > Russ Rew UCAR Unidata Program address@hidden http://www.unidata.ucar.edu Ticket Details =================== Ticket ID: UFR-913429 Department: Support netCDF Priority: Normal Status: Closed