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Weirdness with symbol Degree vis Units

• To: mathgroup at smc.vnet.net
• Subject: [mg40616] Weirdness with symbol Degree vis Units
• From: frankeye at cox.net (Frank Iannarilli)
• Date: Fri, 11 Apr 2003 02:02:17 -0400 (EDT)
• Sender: owner-wri-mathgroup at wolfram.com

Hi,

I threw myself for a loop, trying the following:

Needs["Miscellaneous`Units`"]

Convert[6 Milli Radian, Degree]
   > 0.006

Convert[6 Milli Radian, 1/Degree]
   > 0.006

(* Huh?? What's going on here?? *)

Context[Degree]
   > System`

N[Degree]
   > 0.0174533  (* same as it ever way... *)

Oh, thought I...the Help Browser, when viewing the
StandardAddons/Miscellaneous/Units, lists Degree as a units symbol for
angle. So I'd better reference it with its context:

Convert[6. Milli Radian, Miscellaneous`Units`Degree]
   > Convert::incomp : Incompatible units in 6 Milli Radian and
Degree.

N[Degree]
   > Degree  (* Huh?? *)

It turns out that the Units package does NOT in fact introduce its own
Degree symbol:  (reference:
http://support.wolfram.com/mathematica/kernel/Symbols/Miscellaneous/Units/index.html).

Nevertheless, I inadvertently introduced it myself with the most
recent Convert[] invocation above.  So to get things back to "normal"
I had to Remove it:

Remove[Miscellaneous`Units`Degree]

But now, notwithstanding the somewhat misleading documentation, my
question still remains:  Why can't I have Convert[] give me an
"non-surprising" behavior when attempting to convert to Degree?  Must
I treat the Degree symbol as a special case, w.r.t. use of units?

TIA!

• Follow-Ups:
  • Re: Weirdness with symbol Degree vis Units
    • From: Dr Bob <majort@cox-internet.com>