[fitsbits] 16-bit floats {External}

[Barrett, Paul]

I suggest asking the question: What FITS library cannot handle 16-bit and
128-bit floats?  We know that half-precision is supported in C/C++ and
FORTRAN, which means that it is potentially available in FITSIO, CFITSIO,
and Python/numpy that depend on these languages. It is also available in
Java and Julia. This leaves languages such as IDL, Matlab, and R that may
not be supported, unless the maintainers decide to eventually add those
types. My feeling is that those who use those languages are a small
percentage (<1 %) of the user base. It does not seem reasonable to me that
such a small percentage of users have such a large influence on the
development of our community. It has always been my opinion that a data
format should not control what and how software is developed. It places an
unnecessary constraint on the development of high quality, high performance
software.

 -- Paul


On Thu, Jul 24, 2025 at 5:01 AM jaffe via fitsbits <
fitsbits at listmgr.nrao.edu> wrote:

> Whether a FITS storage format is supported by any programming language,
> or even any machine processor architecture is irrelevant, FITS is a
> transport standard.  If half-precision FP is accepted into the FITS
> standard, this implies that the FITS reader/writers for any language or
> architecture have to be adapted to convert the FITS data into a locally
> functional format, e.g. 32-bit FP if local 16-bit FP is not supported.
>
> Walter
>
> On 2025-07-23 20:11, Lucio Chiappetti via fitsbits wrote:
> > On Wed, 23 Jul 2025, Barrett, Paul via fitsbits wrote:
> >
> >> Yes, definitely. I have been advocating for half-precision (16-bit)
> >> floating point for several years now for radio astronomy. In addition,
> >> 128-bit floats
> >
> > Are these formats supported by any major programming language ?
> >
> > Is it worth supporting "exotic" formats, which might be suitable for
> > some niche application, when most data producers often use improperly
> > 64-bit all the times, even when overshoot ?
> >
> > Historically FITS went the other way round (concentrating on 16 and 32,
> > later 64, when mainframres with 36 or 60 bits were around).
> >
> > _______________________________________________
> > fitsbits mailing list
> > fitsbits at listmgr.nrao.edu
> > https://listmgr.nrao.edu/mailman/listinfo/fitsbits
>
> _______________________________________________
> fitsbits mailing list
> fitsbits at listmgr.nrao.edu
> https://listmgr.nrao.edu/mailman/listinfo/fitsbits
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listmgr.nrao.edu/pipermail/fitsbits/attachments/20250724/d2785b94/attachment.html>