Jim Wilson wrote:
 > But if those settings don't represent a form of units--just arbitrary
 > values, why do they need a suffix?  The suffixes were intended to
 > reflect units and make sense only when they mean something, like
 > knowing if the value is in feet or meters, degrees or radians, knots
 > or fps.

Well, strictly, the suffixes are there to provide context and tell the
user how to interpret the value they get.  Now, it happens that this
corresponds closely to the physical notion of "unit".  But it's not
exact.

In this case, interpreting the "unitless" number requires knowing the
range in which it lives.  A percent value of "0.5" is off by a two
orders of magnitude from the same value interpreted as a fraction in
the range [0:1].  Applying suffixes here to disambiguate them serves
exactly teh same purpose as applying suffixes to disambiguate pounds
from kilograms.  Units or not?  You make the call, but the design
impetus is the same.

Also, a pedantic note: "degrees" and "radians" are both unitless in a
mathematical sense.  Angles have an absolute magnitude that is
invariant with scale, and thus need no units.  Degrees are in fact
exactly like percent -- they are a convenience representation arrived
at by multiplying a unitless number by a scalar constant.

Andy

-- 
Andrew J. Ross                NextBus Information Systems
Senior Software Engineer      Emeryville, CA
[EMAIL PROTECTED]              http://www.nextbus.com
"Men go crazy in conflagrations.  They only get better one by one."
  - Sting (misquoted)


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