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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Radians Or Degrees?
Date: Fri, 23 Feb 2024 18:49:17 -0800
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Ben Bacarisse <ben.usenet@bsb.me.uk> writes:

> Lawrence D'Oliveiro <ldo@nz.invalid> writes:
>
>> On Fri, 23 Feb 2024 23:16:32 +0000, Ben Bacarisse wrote:
>>
>>> Lawrence D'Oliveiro <ldo@nz.invalid> writes:
>>>
>>>> On Fri, 23 Feb 2024 20:38:59 -0000 (UTC), Steven G. Kargl wrote:
>>>>
>>>>> Note 2: subnormal values ...
>>>>
>>>> Why did they bring in the term "subnormal", anyway?  What was wrong with
>>>> "denormalized"?
>>>
>>> Greater clarity maybe?  After all, the two terms do mean different
>>> things.  In IEEE FP only subnormals can exist, but it surely helps to be
>>> able to talk about the difference.
>>
>> I thought they were the same thing:  extra numbers inserted in the gap
>> between the normalized number closest to zero on each side, to allow for
>> gradual underflow.
>
> Those are subnormal.  They are smaller (in magnitude) than the smallest
> normal.  Denormals are simply representations with leading zeros.  IEEE
> FP's implicit leading 1 means these (denormals that are not subnormal)
> can't exist in that representation.

There is some terminology confusion here.  Depending on what
source is consulted, the term "denormal" has different meanings.
On Wikipedia, for example, "denormal numbers" redirects to
"subnormal number".  Apparently the IEEE floating point standard
uses the term differently.  Other sources are not consistent.

Note that the ISO C standard uses and defines the terms "subnormal
floating-point numbers" and "unnormalized floating-point numbers",
as disjoint sets, distinct from normalized floating-point numbers
(which the ISO C standard also defines).  I expect it would help
the conversation to use these three terms (normalized, subnormal,
and unnormalized) and no others, since "denormal" or "denormalized"
seems to mean different things depending on which source is used.