Re: Manipulation of equations and inequalities in "high-school style"
- To: mathgroup at smc.vnet.net
- Subject: [mg19691] Re: Manipulation of equations and inequalities in "high-school style"
- From: Paul Abbott <paul at physics.uwa.edu.au>
- Date: Sat, 11 Sep 1999 16:36:00 -0400
- Organization: University of Western Australia
- References: <7q9hdf$o62@smc.vnet.net> <7r4voh$9qh@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
"William M. MacDonald" wrote:
> I have repeatedly suggested to Wolfram technical staff, and to Stephen
> Wolfram, that Equal be given the same properties for a single equation as
> List, that Listable symbols operate on
>
> Equal[exp1,exp2]
>
> just as they do on
>
> List[exp1,exp2]
But this is simple to implement! Following Roman Maeder, just
enter the following code
Unprotect[Equal];
listableQ[f_] := MemberQ[Attributes[f], Listable]
Equal/: lhs:(f_Symbol)?listableQ[___, _Equal, ___] :=
Thread[Unevaluated[lhs], Equal]
Protect[Equal];
____________________________________________________________________
Paul Abbott Phone: +61-8-9380-2734
Department of Physics Fax: +61-8-9380-1014
The University of Western Australia
Nedlands WA 6907 mailto:paul at physics.uwa.edu.au
AUSTRALIA http://physics.uwa.edu.au/~paul
God IS a weakly left-handed dice player
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