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[netCDF #LWL-894598]: Netcdf4 documentation for Fortran 90 (parallel

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  • Subject: [netCDF #LWL-894598]: Netcdf4 documentation for Fortran 90 (parallel
  • Date: Tue, 07 Apr 2009 11:28:02 -0600
> Hello,
>
> I am looking for Fortran 90 documentation of the netcdf 4.0.1 version.
> In particular, I need to know the details of the parallel IO calls. It
> looks to me like the documentation of the C calls is much more complete
> than the F90 calls. Should I use the C documentation as a place to
> start?

Thanks for pointing this out! This is an oversight that I have just corrected
for the next release. The correct documentation will appear here, after the
daily snapshot release happens around midnight tonight:
http://www.unidata.ucar.edu/software/netcdf/docs_snapshot/netcdf-f90.html

A good place to start now might be the parallel I/O section of the tutorial:
http://www.unidata.ucar.edu/software/netcdf/docs/netcdf-tutorial.html#Parallel

It also cites a C example - the F90 code ultimately calls the C code, so
whatever you read about parallel I/O from C code also applies to the F90 code.

If you build netCDF with --enable-parallel-tests, one of the test that will be
build is nf_test/f90tst_parallel.f90. This program some some simple parallel
access from F90, and would also be a good place to start.

>
> What I'm doing is starting with code that uses parallel-netcdf calls,
> and I'm going to convert that to use netcdf 4 calls. I am quite familiar
> with netcdf in general.
>
> Any advice will be appreciated.
>

First convert to netCDF-4 by adding NC_NETCDF4 to the create mode of your
nc_create call. Then test that everything still works.

After all that, convert to parallel. All metadata operations have to be done
collectively, then the data reads/writes can happen independently.

Let me know if you need more help.

Thanks,

Ed

Ticket Details
===================
Ticket ID: LWL-894598
Department: Support netCDF
Priority: Normal
Status: Closed