[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: netcdf (operators and c++ class)

This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.

  • Subject: Re: netcdf (operators and c++ class)
  • Date: Wed, 12 Oct 1994 10:37:18 -0600
> Organization: Department of Rangeland Ecology and Management, Texas A&M 
> University
> Keywords: 199410111337.AA20941

Hi Dan,

> > We aren't so committed to the way that the netCDF operators were
> > originally specified that we would ignore a better approach.  In fact,
> > I've recently talked to Harvey Davies of CSIRO about what we think is a
> > different and better approach to specifying array sections via a
> > language/notation he has developed called FAN (file-array notation).  He
> > has offered us a program called nc2text (and the opposite text2nc) that
> > uses FAN to specify sequences of data from netCDF variables and
> > incorporates quite a bit of the functionality of several netCDF
> > operators as well as units and type conversion.
> >
> 
> How do I find stuff on FAN (email/ftp/url)?

I just found out about it myself, when Harvey Davies of the CSIRO Division
of Atmospheric Research visited Boulder last week and gave a talk on FAN.
Harvey's email address is address@hidden.  He has an FTP server, but
I don't think the FAN sources are available there yet.  I checked

    ftp://atmos.dar.csiro.au/netcdf/hld/apl94/

where I think there are some relevant papers in TeX form.

> > We originally thought about the idea of developing an interpreter for
> > netCDF expressions that would do everything we wanted to do in the
> > operators, but none of us particularly wanted to design another
> > language.  However I think this is actually a reasonable approach, as
> > has been proven with various interpretive languages that have added
> > netCDF interfaces for I/O, such as IDL and MATLAB as well as Davies FAN.
> > Davies has also implemented a netCDF interface to J, which is a
> > functional descendant of APL.
> 
> Is there a reason that the UCAR site does not reference where to find
> these?

The IDL and MATLAB interfaces are described in the document

    http://www.unidata.ucar.edu/packages/netcdf/utilities.html

with a text version available as

    ftp://ftp.unidata.ucar.edu/pub/netcdf/utilities.txt

I'd like to include a description and reference to FAN and the associated
utilities like nc2text, text2nc, and ncrob in this document.  I'm CC:ing
Harvey on this note in hopes he will provide a brief description and
reference to FTPable sources, if such exist yet.

I'll send a followup on the C++ interface changes you suggested in a
subsequent reply.

--
Russ Rew                                                UCAR Unidata Program
address@hidden                                          P.O. Box 3000
http://www.unidata.ucar.edu/                          Boulder, CO 80307-3000