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Re: Reading CDF Files

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  • Subject: Re: Reading CDF Files
  • Date: Wed, 30 Sep 1998 12:25:00 -0600
Hi Neil,

> I work and write special software for chromatographic analyses.  Data
> Systems for Chromatography generally now have capability to store data in
> AIA (ANDI) *.CDF files.  I am trying to understand how to import this data
> into my software.  I am using Visual Basic 4.0 (16bit), 32bit when users
> quit using Windows 3.1.
> 
> I have obtained the ASTM documents E1947 and E1948 as well as the guide from
> your web site.  I'm not very experienced at reading binary files, so am
> still confused.
> 
> Is there any assistance that you can offer to me?  I live in Lafayette, CO
> so could easily visit your facilities, if that would be an option.

I'm not familiar with the ASTM documents E1947 and E1948 (are they
available online?), but I know that our netCDF data access interface and
software were adopted some time ago as some sort of standard for
chromatography data.  Incidentally, since about 1990 we have recommended
the use of the ".nc" extension instead of ".cdf" for netCDF files, to
avoid confusion with NASA's CDF format.

Unfortunately, I am not aware of any software for reading netCDF files
from Visual Basic.  We use C, Fortran, C++, perl, and Java, and have
developed netCDF interfaces for all these languages, but the users for
whom we develop software don't use Visual Basic.

We do have a DLL library available for netCDF, in the directory

  ftp://ftp.unidata.ucar.edu/pub/netcdf/contrib/win322

and it's my understanding that it's possible to call DLL library
routines from Visual Basic, though it may be necessary to provide some
kind of wrappers to conform to the Visual Basic calling conventions.

Looking up "netcdf" and "visual basic" with the HotBot search engine, I
found the following in a report at

 http://www.xdc.arm.gov/common/ARM/docs/monthrpt/rpt9802.html

    ...
    SYSTEM DEVELOPMENT AND ENGINEERING

    David Olivares is working on converting the netCDF viewer, developed
    by Brian Ermold  from Visual Basic to Java. He has been consulting
    with Brian and Laurie about this activity.
    ...

so that might be a lead.

You're welcome to visit our office, but it might be more useful to post
a query about this to the address@hidden mailing list.
There may be someone on that list (500 to 1000 netCDF users) to see if
anyone else has solved this problem.  You have to be a member of the
mailing list before you post to it; see

  http://www.unidata.ucar.edu/packages/netcdf/mailing-lists.html

--Russ
_____________________________________________________________________

Russ Rew                                         UCAR Unidata Program
address@hidden                     http://www.unidata.ucar.edu