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Re: Re: Re: Re: Newly Released Mathematica 5.1 Delivers Unmatched Performance for Handling Data

• To: mathgroup at smc.vnet.net
• Subject: [mg52408] Re: [mg52396] Re: Re: Re: Newly Released Mathematica 5.1 Delivers Unmatched Performance for Handling Data
• From: "David Park" <djmp at earthlink.net>
• Date: Fri, 26 Nov 2004 01:04:38 -0500 (EST)
• Sender: owner-wri-mathgroup at wolfram.com

John,

I was thinking of angular measurement. The following works...

Needs["Miscellaneous`Units`"]

Convert[(Pi/4)*Radian, °]
45 °

but the following, using an approximate value, does not work because Degree
immediately multiplies out undoing the conversion.

Convert[1.35 Radian, °]
1.35

The ExtendUnits package at my web site fixes this but at the expense of
putting a HoldForm on the degree symbol.

Needs["Miscellaneous`V4ExtendUnits`"]

1.35 Radian // ToUnit[°]
% // FullForm
77.3493 °
Times[77.34930234266115`, HoldForm[Degree]]

Since I generally consider value substitution and unit conversion as the
last step in a physical calculation this is not a huge problem. Still it
would be nice if units and numerical constants had different names.

David Park
djmp at earthlink.net
http://home.earthlink.net/~djmp/






From: John Jowett [mailto:John.Jowett at cern.ch]
To: mathgroup at smc.vnet.net


I'm not sure that it is necessary to have a unit Degree as Kelvin is already
there and is used, e.g., in the definition of BoltzmannConstant.   The
Miscellaneous`Units` has a special handling of temperature scales
(ConvertTemperature) that are not proportional to each other like other
units.   It seems a bit clumsy but I don't have much occasion to use it
myself.   Otherwise
Convert[5 Fahrenheit, Kelvin]

returns something that might be considered reasonable, with a warning
message.

"David Park" <djmp at earthlink.net> wrote in message
news:co1ejp$shb$1 at smc.vnet.net...
> John,
>
> Your idea about non-conflicting color names seems good. Also there should
be
> a unit Degree and a different name for the numerical constant.
>