Re: How To Change A Rule
- To: mathgroup at smc.vnet.net
- Subject: [mg32375] Re: How To Change A Rule
- From: Clemens Frey <frey at mathematik.tu-darmstadt.de>
- Date: Thu, 17 Jan 2002 02:23:27 -0500 (EST)
- Organization: TU Darmstadt
- References: <a20mon$4hf$1@smc.vnet.net>
- Reply-to: frey at mathematik.tu-darmstadt.de
- Sender: owner-wri-mathgroup at wolfram.com
Hi,
you may use a simple transformation with a conditional pattern.
Having a list of rules named rlst:
IN[1]:= rlst = {s1 -> -11, s2 -> 12}
then the following
IN[2]:= rlst2 = rlst /. Rule[x_, y_ /; y < 0] -> Rule[x, 0]
sets rlst2 to be the following list of rules:
OUT[2]= {s1 -> 0, s2 -> 12}
Hope that helps.
Clemens
Ariel Fligler wrote:
>
> Greetings,
>
> I'm quite newby to Mathematica programming and will thank you if you could
> help me solve the following:
>
> I have a list of rules of the form:
> {s1->-11, s2->12}
> And would like to change every rule in the list that it's RHS is negative to
> 0 so that I will get:
> {s1->0, s2->12}
> I tried to find an access function to manipulate rules but could not.
>
> Any help ?
>
> TIA,
>
> Ariel.
>
> Thanks,
>
> Ariel Fligler
--
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Clemens Frey phone: +49-6151-164706
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