Re: "Alternating" function
- To: mathgroup at smc.vnet.net
- Subject: [mg63271] Re: [mg63260] "Alternating" function
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Thu, 22 Dec 2005 00:04:33 -0500 (EST)
- Reply-to: hanlonr at cox.net
- Sender: owner-wri-mathgroup at wolfram.com
expr=x+f[x-f[x+f[x-f[x+f[x]]]]];
expr==Module[{n=1},
Nest[x-(-1)^n++*f[#]&, x, 5]]
True
expr==Module[{n=1},
Nest[x-Cos[Pi*n++]*f[#]&, x, 5]]
True
Bob Hanlon
>
> From: Renan <renan.birck at gmail.com>
To: mathgroup at smc.vnet.net
> Date: 2005/12/20 Tue PM 11:35:44 EST
> Subject: [mg63271] [mg63260] "Alternating" function
>
> Hello,
>
> I want to make a "nested function" like: x + f[x - f[x + f[x - f[x + f[x]]]]].
>
> I've tried using Nest but I don't find how to keep switching between
> Plus and Minus: I would need something that would return an "index" so
> I could keep track of when I need to "switch" the operation. (e.g. if
> the "index" is odd, the operation is "Plus", otherwise is "Minus")
>
> How can I make this? I looked in the help but didn't find any informations.
>
> Thanks.
>
>
>
>
> --
> Thanks/obrigado, Renan "Wishmaster" Birck - Canoas, Rio Grande do Sul, Brasil
> MSN: wizard_of_yendor at hotmail.com
> Orkut: http://www.orkut.com/Profile.aspx?uid=2202360379963855296
>
>