Usenet 1994 October/usenetsourcesnewsgroupsinfomagicoctober1994disk1.iso/answers/sci-data-formats

Text File | 1993-12-29 | 13KB | 311 lines

Newsgroups: sci.data.formats,news.answers,sci.answers
Path: bloom-beacon.mit.edu!news.kei.com!sol.ctr.columbia.edu!howland.reston.ans.net!agate!ames!ncar!kiowa.scd.ucar.edu!ilana
From: [e-mail] (Ilana Stern)
Subject: Scientific Data Format Information FAQ
Message-ID: <[e-mail]>
Followup-To: sci.data.formats
Summary: Where to find information on scientific data formats
Sender: [e-mail] (USENET Maintenance)
Reply-To: [e-mail]
Organization: NCAR/UCAR
Date: Wed, 29 Dec 1993 12:00:11 GMT
Approved: [e-mail]
Expires: Tue, 12 Jan 1993 07:00:00 GMT
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Xref: bloom-beacon.mit.edu sci.data.formats:341 news.answers:13435 sci.answers:768

Archive-name: sci-data-formats
Last-modified: 22 Dec 1993

Recent changes:

  ==within last two weeks==

  ==within last four weeks==
Added information about CSCDF



This is the FAQ for the sci.data.formats newsgroup.  Contents:

-2)  How to use this document
-1)  How to get a current copy of this document
 0)  Resources for format information
 1)  How to use the data retrieval methods
 2)  Why isn't my favorite format on this list?

Each (major) section has a "Subject:" line, so you can search on the
subject title above to find the section quickly.

This article is copyright (c) 1993 by Ilana Stern.  It may be freely
distributed provided that this copyright notice and the information
on retrieving a current copy are not removed.

Comments, corrections, or additions should be sent to Ilana Stern
at [e-mail].

---------------
Subject:  How to use this document

  Most FAQ (Frequently Asked Questions) documents list many questions and
their answers.  This FAQ is (mostly) devoted to answering only one question:

"Where can I find documentation and software for [X] data format?"

  As the amount of information available over the networks has been
increasing, so have the methods by which this information can be obtained.
No longer is direct usage of FTP the only, or even the most frequent, method
of obtaining data;  we now have Gopher, Wais, and WWW, as well as many
site-specific interfaces.  Because the information itself may be accessible
in many different ways, this FAQ will identify resources in terms of
URLs (Uniform Resource Locators).  This will also help us convert this
FAQ to a hypertext document, so that it can be used with a WWW browser
to go directly to any of the listed sources.
  Here's a glossary, so you can decode the URLs if necessary to reach
the sites:

    ftp://host.name.domain/directory/[filename]    ftp site
    http://host.name.domain/directory/[filename]    www server
    telnet://host.name.domain            telnet site
    gopher://host.name.domain            gopher server
    wais://host.name.domain                wais server
    news:newsgroup.name                newsgroup

  So, for example, if a document is available at ftp://ncardata.ucar.edu/
it means that you should ftp to ncardata.ucar.edu, and the information is
in the top-level directory.
  If you don't know what these information retrieval methods are, see
the section "How to use the data retrieval methods".

---------------
Subject:  How to get a current copy of this document

  If you are reading this document after 12 Jan 1993, you are reading an
outdated copy. A current copy of this document can be obtained by anonymous
FTP to ftp://rtfm.mit.edu/pub/usenet/news.answers/sci-data-formats.
If you don't know what FTP is, see the section "How to use the data retrieval
methods".

If you can't use FTP, send email to [e-mail] with
    send /pub/usenet/news.answers/sci-data-formats
  as the only text in the message (leave the subject blank).

A current hypertext version of this document can be obtained from
http://fits.cv.nrao.edu/traffic/scidataformats/faq.html, from
http://www.ncsa.uiuc.edu/SDG/Software/HDF/SciDataFormatsFAQ.html,
or (for European users in particular) from
http://info.mcc.ac.uk:80/CGU/Visualisation/sdf.html.  If
you would like to archive this FAQ in either hypertext or plaintext
format, and want to receive a new copy automatically at every update,
please send me email.

---------------
Subject:  Resources for format information

1) CDF
2) FITS
3) GRIB
4) HDF
5) netCDF
6) Miscellaneous graphics formats

1. CDF
  CDF (Common Data Format) is a library and toolkit for multi-dimensional
data sets.  The basic component of CDF is a software programming interface
that is a device independent view of the CDF data model.  A user's guide
and software is available from ftp://nssdca.gsfc.nasa.gov/cdf/.
[Note: this is a VMS FTP site and can't be reached via Xmosaic -- if you
are reading the hypertext version of this FAQ, use
ftp://hypatia.gsfc.nasa.gov/nssdc_anon/cdf/ instead.]
  Questions can be directed to [e-mail].
  A client-server software layer called CSCDF, which can be used with
the CDF library to provide applications access to remote CDF datasets,
can be obtained from its author, Hillel Steinberg, by email at
[e-mail].

2. FITS

  FITS (Flexible Image Transport System) is the standard data interchange
and archival format of the worldwide astronomy community.  The NOST Standard
and User's Guide, some software, and test files are available from
ftp://nssdca.gsfc.nasa.gov/fits/ by direct ftp, or from
ftp://hypatia.gsfc.nasa.gov/nssdc_anon/fits/ via a WWW browser.
  The site ftp://fits.cv.nrao.edu/fits (accessible via WWW at
http://fits.cv.nrao.edu/) has other software and a different set of test files,
and electronic copies of FITS proposals that are under development or in the
international approval process.  Archives of news:sci.data.formats and
news:sci.astro.fits (which is devoted to discussion of FITS) that are of
interest to astronomers can be found in ftp://fits.cv.nrao.edu/fits/traffic/.
  A WAIS index that can be searched for FITS information is at
http://info.cern.ch:8001/fits.cv.nrao.edu:210/nrao-fits.
  If you've searched all these resources and still have questions, you
can direct them to [e-mail].

3. GRIB

  GRIB (GRid In Binary) is the World Meteorological Organization (WMO)
standard for gridded meteorological data.  Unfortunately it is still not
very "standard", as some organizations use their own versions.  A format
description for WMO GRIB can be found at
ftp://ncardata.ucar.edu/datasets/ds084.5/format_grib,
and read code is in the file access_grib.f in the same directory.
  If you need GRIB to read ECMWF data, the above format description, along
with the ECMWF-specific parameter table, and a list of differences between
WMO and ECMWF GRIB, is in ftp://ncardata.ucar.edu/datasets/ds111.2/format.
Read code can be found in ftp://ncardata.ucar.edu/datasets/ds111.2/software.
  If all else fails, contact Ilana Stern at [e-mail].

4. HDF

  HDF (Hierarchical Data Format) is a self-defining file format for transfer
of various types of data between different machines. The HDF library contains
interfaces for storing and retrieving compressed or uncompressed raster images
with palettes, and an interface for storing and retrieving n-Dimensional
scientific datasets together with information about the data, such as labels,
units, formats, and scales for all dimensions.
  Source code and documentation are on ftp://ftp.ncsa.uiuc.edu/HDF.
Some general information on HDF, including a FAQ, is available from
http://www.ncsa.uiuc.edu/SDG/Software/HDF/HDFIntro.html.

5. netCDF

  NetCDF (Network Common Data Form) is an interface for scientific data
access which implements a machine-independent, self-describing, extendible
file format.  Source code and documentation for the netCDF data access library
is available from ftp://ftp.unidata.ucar.edu/pub/netcdf or
gopher://gopher.unidata.ucar.edu:70.  A FAQ is here also, as well as pointers
to other available software packages which use netCDF data.  Questions and
answers about netCDF can be searched in the index
wais://wais.unidata.ucar.edu:210/unidata-support-netcdf.src.
  A recent paper (Jenter and Signell, 1992) which provides a good introduction
to netCDF is available as ftp://crusty.er.usgs.gov/pub/netcdf.asce.ps.
  A mailing list, [e-mail], exists for discussion of the
netCDF interface, and for announcements of netCDF news:  to subscribe, send
a request to [e-mail].  The archives of netcdfgroup
are available from ftp://ftp.unidata.ucar.edu/mail-archives/netcdfgroup,
and also in the searchable index
wais://wais.unidata.ucar.edu:210/netcdf-group.src.
  For more information, contact [e-mail].

6. Miscellaneous graphics formats

  These formats for storing graphics files -- TIFF, GIF, JPEG, FLI, CGM,
and so on -- are more properly discussed in news:comp.graphics.  A small
amount of documentation on these and other graphics formats is on
ftp://zamenhof.cs.rice.edu/pub/graphics.formats;  other archive sites
are ftp://ftp.ncsa.uiuc.edu/misc/file.formats/graphics.formats, and
ftp://telva.ccu.uniovi.es/pub/graphics/Image.
  The comp.graphics FAQ and resource file have more information on where
to find read and conversion programs for these formats.  You can find
them at ftp://rtfm.mit.edu/pub/usenet/news.answers.
  A good (hardcopy) reference for graphics formats is  _Graphics
File Formats_, by David C. Kay and John R. Levine (Windcrest Books,
ISBN 0-8306-3060-0, about US$30.00 in paperback).

---------------
Subject:  How to use the data retrieval methods

  This section only describes FTP and telnet in any detail;  for other
methods, FTP sites are given, so you can get information on them yourself.

1) How to use FTP
2) How to use telnet
3) Gopher information
4) Wais information
5) WWW information

1. How to use FTP

FTP (File Transfer Protocol) allows transfer of files between two computers
which are on the Internet.  To access the FTP areas listed here, at your
system prompt type "ftp" followed by the name of the desired system.  For
example, to access ncardata.ucar.edu you'd type

    ftp ncardata.ucar.edu

Use "anonymous" as your login and your email address as the password (if
requested).

[Note: quotes ("like this") are used to set off names of directories and
files, or commands you'd type, and are not part of these names.]

Not all FTP systems accept the same commands, but here's a list of the
most useful:

    ls      list files in the current directory.
    cd      change directory, e.g. "cd wx" changes to the wx directory.
    binary  sets binary mode
    ascii   sets ascii mode (the default).  Use for retrieving text.
    get     retrieves a file, e.g. "get readme" gets a file called readme.
    bye     exits FTP.

If you can't seem to connect to the site, check to see if it is a telnet
site.  If it is, follow the instructions in the following section instead.

If you can't FTP from your site, use one of the following ftp-by-mail servers:

    [e-mail]
    [e-mail]
    [e-mail]
    [e-mail]

Send an e-mail message to the closest address, with the lines:

    reply [e-mail]     <- with your email address
    connect ncardata.ucar.edu         <- for example
    cd datasets/ds111.2/software
    get access_sun.f
    quit

For complete instructions, send a one-line message reading "help" to the
server.  Please don't ask me for help!

2. How to use telnet

Type "telnet" followed by the name or IP number of the desired system.  These
publicly accessible systems generally allow you to log in but put you in
a restricted shell, from which only a certain menu of commands is available.
The description for the site will include the login to use.

If you can't seem to connect to the site, re-check its description in the
document; if it's an FTP site, follow the instructions in the previous
section instead.

3. Gopher information

Available by ftp at ftp://rtfm.mit.edu/pub/usenet/news.answers/gopher-faq.

4. Wais information

Available by ftp at
ftp://rtfm.mit.edu/pub/usenet/news.answers/wais-faq/getting-started.

5. WWW information

Available by ftp at ftp://rtfm.mit.edu/pub/usenet/news.answers/www/faq.
WWW is so easy to use that you might as well just hop in and try it, so
ask your sysadmin if you have a WWW browser such as NCSA Mosaic.

---------------
Subject:  Why isn't my favorite format on this list?

  If you don't see a format you're interested in here, it could be one
of three reasons.  First of all, there are a lot of formats which are
out of the scope of this newsgroup:  it ain't named *sci*.data.formats
for nuthin', you know.  Formats used in commercial spreadsheet and
word-processing software aren't scientific data formats, and aren't
discussed in this group.

  Second, it may be that nobody has given the FAQ organizer any information
on sources for information on that format.  So ask the newsgroup -- and
if you do get a response, please let me know what it is!

  Finally, you may ask on the net, and hear nothing, because the
data format description just *isn't* publicly available.  For most
scientific data formats, this is a Bad Thing, and most archivists and
scientists *want* to have their format information available.  If
you have such information, but don't have resources to make it
available, please ask around and see if you can get it into an FTP
area or other resource.  Please don't publicize private or proprietary
formats without the permission of the author, though.