[cfp-interest 3483] Magnitude or Absolute Value or |x| or ....

[Damian McGuckin]

Can the standard assume that a reader will understand the concept and 
interchangeability of the above terms.

There are about 70 occurrences of magnitude and just 19 occurences of 
"absolute value".

Do they need to be defined in the "Terms, definitions and symbols" of 
Section 3 for that matter?  Should |x| also appear there just as the 
symbols for ceil and floor do?

Those terms appear in lockstep as "magnitude (absolute value)" a few times 
prior to Section 7 where the parentheses do not imply normative text which 
I find a bit distracting.

In Section 7, magnitude stands on its own feet and from then on, is the 
dominant term. The term "magnitude (absolute value)" appears once in Annex 
E but generally the term is magnitude.

Strangely the word "magnitude" never appears in the description of the 
fabs() family of routines which says they return |x|.

When describing the domain to qualify special cases in Annex F, |x| is 
used throughout rather than "absolute value of x" or "magnitude of x". In 
a single place in Annex F, for hypot(), the term "absolute value of x" is 
used to specify the return value of hypot() whereas I note that |x| is 
used as the return value of fabs(). And those words "absolute value" is 
the sole use of the term in Annex F. Why not |x| or even magnitude?

Should we try and clean these up?

<ASIDE>
I should note that Swift has recently hijacked the meaning of magnitude 
for a complex number which is wrong mathematically. Not a very wise 
decision in my humble opinion. Less than help. Why? For speed apparently, 
but it makes no sense.  Gauss and Euler would be turning in their graves
</ASIDE>

Thanks - Damian