[fitsbits] Start of the 'INHERIT' Public Comment Period

[Robert Hanisch]

I have to express some concern about registering the INHERIT convention.
The documentation notes a number of potential problems that can occur when
FITS software that is unaware of the convention is used to read, interpret,
and write new copies of files that use INHERIT.  I consulted with Perry
Greenfield, one of the authors of the document, as to whether these problems
arise in practice or not.  He said yes, indeed, they do, and that he would
prefer to discourage people from using the convention.

If we are to include INHERIT in the FITS registry, we should perhaps do so
solely to document the practice.  However, it seems to me too fragile a
construct to recommend for wider adoption.  It would be cleaner, I think, to
define more clearly the rules for how primary headers pertain to extension
headers (e.g., the concept of inheritance applies by default, or whatever).
This is something we might recommend to the recently formed FITS review
panel to discuss.

Bob


On 3/23/07 4:06 PM, "William Pence" <pence at milkyway.gsfc.nasa.gov> wrote:

> This is to announce the start of the 30-day Public Comment Period on the
> 'INHERIT' FITS convention that has been submitted by the Nelson Zarate
> and Perry Greenfield for inclusion in the 'Registry of FITS Conventions'
> that is maintained by the IAU FITS Working Group.  This is the 4th in a
> growing series of conventions submitted for inclusion in the Registry.
> 
> A document describing this convention and a sample FITS file that uses
> it are available for public review and comment from the FITS registry
> web page at
> 
>          http://fits.gsfc.nasa.gov/fits_registry.html
> 
> Under this convention, the presence of the keyword INHERIT = T in an
> extension header indicates that the extension should inherit the
> keywords from the primary header (except for the mandatory and
> commentary keywords)
> 
> Comments may be posted here on the FITSBITS mail exploder or the
> sci.astro.fits newsgroup.  Minor typographical issues may be sent
> directly to the authors of the convention.
> 
> Bill Pence
> (on behalf of the IAU FITS Working Group)