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Re: Finding length in recursive definition?

  • To: mathgroup at smc.vnet.net
  • Subject: [mg60895] Re: Finding length in recursive definition?
  • From: "Scout" <mathem at tica.org>
  • Date: Sun, 2 Oct 2005 01:54:46 -0400 (EDT)
  • References: <dhlcj2$d16$1@smc.vnet.net>
  • Sender: owner-wri-mathgroup at wolfram.com

Hi Jose,
If I've well understood your question
about how many values of a recursive function f[] are stored in memory,
you can try this:

    Length[DownValues[f]] - 1

where -1 counts the definition of f[] itself.

    ~Scout~

"Jose Reckoner"
>I have something like:
> f[1] = 1
> f[2] = 3
> f[n_] := f[n] = f[n - 1] + f[n - 2]
>
> and in the course of work, f[n] gets evaluated an unknown number of
> times resulting in
>
>>> ?f
> f[1] = 1
> f[2] = 3
> f[3] = 4
> f[n_] := f[n] = f[n - 1] + f[n - 2]
>
> I want to figure out the greatest integer n such that f[n] has already
> been computed and is stored. In this case, it is 3.
>
> How can I do this?
>
> Thanks!
>
> Jose
> 


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