bug#47302: 27.1; calc math-format-number formatting for floats without decimals is unusual

[Jelle Licht <jlicht@fsfe.org>]

Mattias Engdegård <mattiase@acm.org> writes:

> 21 apr. 2021 kl. 17.16 skrev Stefan Kangas <stefan@marxist.se>:
>> 
>> Jelle Licht <jlicht@fsfe.org> writes:
>
>>> (calc-eval "123.0") ; => "123."
>>> (calc-eval "0.0") ; => "0."
>>> 
>>> I would expect this output to be either "123.0" or "123" and "0.0" or
>>> "0" respectively.
>
> Jelle, thanks for the report!
>
> Calc distinguishes integers from floating-point numbers by the presence of a decimal point, so removing it is probably not a good idea. The lack of a trailing 0 after the decimal point is clearly intended but mainly a cosmetic issue; it's uncommon in hand-writing but not in computerese.
>
> We could put a 0 after the decimal point but not doing so saves some space in the often narrow Calc windows. I'd suggest leaving it as it is. The notation is distinctive enough that there is no serious risk of misunderstanding.
>
> If you disagree, do say.
Hi Mattias,

It would be nice to have a (formatting) option to print 'full'
floating-point numbers. There are a lot of other knobs to tweak
w.r.t. printing numbers, so in that sense it does not seem totally
inconceivable for such a thing to exist.

The context in which I would use this is one where the output of calc is
being used by other programs and data formats (e.g. JSON). For now, I'll
just have to have emacs read and then subsequently print the result of
my calc-adventures, which works fine.

Thanks for the consideration,
 - Jelle