Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
2005
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*November
*December
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 2005

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Recursion

  • To: mathgroup at smc.vnet.net
  • Subject: [mg62309] Re: Recursion
  • From: Bill Rowe <readnewsciv at earthlink.net>
  • Date: Sat, 19 Nov 2005 23:18:35 -0500 (EST)
  • Sender: owner-wri-mathgroup at wolfram.com

On 11/19/05 at 5:53 AM, JikaiRF at aol.com wrote:

>I would like to obtain trajectories with respect to x, from the
>following relationship:

>x(t+1)=a x(t)(1-x(t))

>Here, a means a constant with a constraint, 1 < a < 4, t   a
>positive integer and x a variable. I know this difference equation
>cannot be solved by mathematics directly, because it is not linear.
>So, I would like to follow a numerical series in terms of x, and I
>need to know how to program Mathematica for this.

This can be accomplished with NestList, i.e.,

NestList[a #(1-#)&, t, n]

will list of n+1 items with the first being t and each subsequent term being ax(1-x) where x is the preceding term.

Another possiblility is

FixedPointList[a #(1-#)&, t]

This will return a list that ends with the last two elements being the same *assuming* a is chosen so there is convergence. 
--
To reply via email subtract one hundred and four


  • Prev by Date: Re: Recursion
  • Next by Date: Re: Recursion
  • Previous by thread: Re: Recursion
  • Next by thread: Re: Recursion