Re: GDSG Units description

[Shaun McCance <shaunm gnome org>]

On Wed, 2008-08-20 at 16:39 -0400, endolith wrote:
> Some discrepancies on the GDSG Units description
> (http://library.gnome.org/devel/gdp-style-guide/2.22/units.html.en):
> 
> 1. "Kilobit" and "Megabytes"
> 
> In SI, written-out prefixes are always lowercase, so this should be
> "kilobit" and
> "megabyte". (http://physics.nist.gov/Pubs/SP811/sec06.html#6.2.2)
> Only abbreviations are capitalized.  I'd change "Zero" to "zero", as
> well.
> 
> 2. "The recommended units in the following table are based on the
> Systeme International d'Unites (SI) system of units."
> 
> Most of those units are not part of SI at all.  :)  (Only seconds,
> meters, and deg C).  I'd say something like "the recommended style for
> Gnome is the same as SI style rules"
> 
> 3. "Kb"
> 
> If you're using k- = 1000 (which is usually the case for bits), the k
> is lowercase according to SI.  Also, I'd recommend not ever
> abbreviating "bit", since it's already short and "b" is ambiguous.
> Writing out "bit" always is recommended by IEC and NIST as well
> (http://physics.nist.gov/cuu/Units/binary.html and
> http://www.iec.ch/zone/si/si_bytes.htm)  We should say "kB" for 1,000
> bytes, not "KB" or "Kb", and "kbit/s" for 1,000 bit/s, not "Kbps".
> 
> 4. binary multipliers K and M
> 
> This is a point of contention, but the standards say k- = 1,000 and M-
> = 1,000,000, no exceptions.  SI specifically says "These SI prefixes
> refer strictly to powers of 10. They should not be used to indicate
> powers of 2 (for example, one kilobit represents 1000 bits and not
> 1024 bits)."  This is also recommended in the Linux Programmer's
> Manual (man 7 units), used in the kernel, lots of FOSS software, etc.
> As currently written, you define the multipliers in two conflicting
> ways on the same page (M = 10^6 and M = 2^20)  I'm sure this point
> needs discussion before changing, but I'd recommend following the
> standards and using Ki- = 1,024, Mi- = 1,048,576.  Most things should
> be measuring in 1,000s anyway (k/M/G), so it will still be familiar
> abbreviations, just with consistent, correct meanings.

We're currently in the slow process of rewriting the Style Guide.
We will get to the section on units, and hopefully we can come to
an agreement within the community for a sane recommendation.  I've
filed a bug here:

http://bugzilla.gnome.org/show_bug.cgi?id=548862

Note that the same issue is also being discussed for the HIG here:

http://bugzilla.gnome.org/show_bug.cgi?id=309850

--
Shaun