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MathGroup Archive 2004

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RE: Re: Anyone using the Units package extensively?

  • To: mathgroup at smc.vnet.net
  • Subject: [mg45712] RE: [mg45689] Re: Anyone using the Units package extensively?
  • From: "David Park" <djmp at earthlink.net>
  • Date: Wed, 21 Jan 2004 04:54:55 -0500 (EST)
  • Sender: owner-wri-mathgroup at wolfram.com

Bill,

The problem occurs in converting real numbers to Degree.

Needs["Miscellaneous`Units`"]

The following works...

Pi/4
Convert[%, Degree]
Pi/4
45 °

The following does not (because Degree coverts the result right back to
Radians)...

1.57
Convert[%, Degree]
1.57
1.57

1.57 Radian
Convert[%, Degree]
1.57 Radian
1.57


We could do this but then we lose the degree sign

1.57/Degree
89.9544

With the ExtendUnits package from my web site...

Needs["Miscellaneous`V4ExtendUnits`"]

1.57 // ToUnit[Degree]
89.9544 °

1.57 Radian // ToUnit[Degree]
89.9544 °

but ° is put in a HoldForm.

On a different topic, I notice that many people on MathGroup use addresses
that are not usable for replies or that need to be changed for a reply. In
your case I'm not certain if the address is good or how I would subtract one
hundred and four from it. I know how awful spam and virus email is and still
one should be able to have a usuable email address without engaging in
puzzles for responders to solve. I didn't want to use a fake or scrambled
email address but at the same time my email address was becoming almost
complete unusable. Two months ago I subscribed to a service, SpamArrest,
which 99.9% solves the problem. I know that Earthlink has a similar service
and there may be others. One has an approved senders list and new real
people can get on the list by going through a one-time verification process
that involves typing in a word displayed in a graphic. Machines and software
can't do it (yet!) and spammers don't find it cost efficient since they can
immediately be removed or put on a block list. Now I feel like I own my
email address. When I get an email it's real. It also works with MathGroup
email, which I get sent to me directly.

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




From: Bill Rowe [mailto:readnewsciv at earthlink.net]
To: mathgroup at smc.vnet.net

On 1/19/04 at 5:15 AM, djmp at earthlink.net (David Park) wrote:

> Yes, but the problem is that if one is using the Units package then Degree
> is both a Unit and a Mathematica Constant. The usages conflict and I
believe
> it was a mistake in design.

Perhaps I am missing something, but I don't see a conflict here. Whether I
have the package Miscellaneous`Units` loaded or not, I can do things like

Plot[Sin[x Degree], {x, 0, 180}] or
Plot[x/Degree, {x, 0, 1}]

And get the expected result.

Where is the conflict?

Bill
--
To reply via email subtract one hundred and four



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