[R] Iterative Solver [Converting Matlab's solve()]

[Robert A LaBudde]

At 12:24 AM 6/19/2007, Boris wrote:
>I can't for the life of me figure out how to get the roots for this simple
>(but sovable only iteratively) equation in R:
>
>x = z*(1-(1-2/z)^y
>
>where x and y are known, and z is unknown. In Matlab, this amounts to:
>
>[my.solution] = solve('x = z*(1-(1-2/z)^y')
>my.solution.real = solution(y-1,y)
>
>% bottom line displays non-imaginary solution (last element)
><snip>

1.  Your equation is syntactically incorrect. It is missing a ")". 
Ditto for your Matlab example.

2. Are you looking for an analytical (symbolic) solution? If so, I 
don't believe one exists (if you place a ")" after y).

3. To find numerical roots, see uniroot().

4. If you want more help, you'll have to specify domains or values for x and y.

================================================================
Robert A. LaBudde, PhD, PAS, Dpl. ACAFS  e-mail: ral at lcfltd.com
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