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Re: Transformation rule exercise

• To: mathgroup at smc.vnet.net
• Subject: [mg4940] Re: [mg4898] Transformation rule exercise
• From: Xah Lee <xah at best.com>
• Date: Mon, 7 Oct 1996 02:02:11 -0400
• Organization: Best Internet Communications
• Sender: owner-wri-mathgroup at wolfram.com

> Date: Fri, 4 Oct 1996 00:17:36 -0400
> From: rhall2 at umbc.edu (hall robert)
To: mathgroup at smc.vnet.net
> To: mathgroup at smc.vnet.net
> Subject: [mg4898] Transformation rule exercise
> ... exercise 4 from p. 113 of
> Introduction to Programming with Mathematica, by Gaylord, Kamin & Wellin.
> The problem is to rewrite
>         g[x_] = x /. Plus[z___] -> Times[z]
> so that 
>         g[a + b + c] 
> returns 
>         a b c
>...
> I'm looking for a solution to which the
> authors' hint applies...

I'm not sure what if the following is what you are looking for.

g[x_] := ReleaseHold[ Hold[ Plus[3,4,5] ] /. Plus->Times]

 Xah
 xah at best.com; 74631.731 at compuserve.com
 http://www.best.com/~xah/SpecialPlaneCurves_dir/specialPlaneCurves.html
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