[fitsbits] start of Public Comment Period on the INHERIT convention

[Mark Taylor]

On Wed, 24 Jun 2015, Mark Calabretta wrote:

> On Tue, 23 Jun 2015 14:14:42 +0100 (BST)
> Mark Taylor <m.b.taylor at bristol.ac.uk> wrote:
> 
> Hi Mark,
> 
> > The main worry I have is the possibility of INHERITed keywords
> > that make a significant difference to the way that an inheriting
> > HDU is processed.  For instance if a PHDU has a set of TFORMn
> > keywords that are INHERITed by subsequent BINTABLE extensions
> > (which themselves lack those keywords), then the file will look
> > legal to a reader which is aware of INHERIT but illegal to one
> > which is not.  In that context, Lucio's comment:
> 
> I believe there is a loophole in the standard that needs plugging;
> it should prohibit table-specific keywords appearing in the primary
> header:
> 
>   TFIELDS, TTYPEn, TBCOLn, TFORMn, TUNITn, TSCALn, TZEROn, TNULLn,
>   TDISPn, TDIMn, THEAP, (and potentially, TDMINn, TDMAXn, TLMINn,
>   TLMAXn), plus all of the table-specific WCS keywords.

I would certainly feel more relaxed about it if this point was
addressed explicitly in the text.

--
Mark Taylor   Astronomical Programmer   Physics, Bristol University, UK
m.b.taylor at bris.ac.uk +44-117-9288776  http://www.star.bris.ac.uk/~mbt/