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

[Mark Calabretta]

On Sun, 5 Jul 2015 12:10:10 -0400
Erik Bray <embray at stsci.edu> wrote:

>Unfortunately the ship has already sailed on that one when it comes to
>FITS, due to the use of comments to store unit information.

CUNITia is supposed to be used for units on WCS keywords, but many,
such as angles, have fixed units (deg).  For the remainder, it was an
largely attempt to rationalise past practice.

I wouldn't recommend it as a model for future practice, though the
alternative of creating a separate units keyword for each of the
recognised keywords would have been cumbersome, and what else could
you do for non-standard keywords?

For CHECKSUM and DATASUM it's easy to do it the "right" way.

Regards,
Mark Calabretta