[R] Find zeros of analytic functions

[Robin Hankin]

>> Dear Partecipants to the list,
>
>> I am Enrico Foscolo, a student of the Faculty of Statistics,  
>> University of Bologna,
>> and I am interested under consideration of the search of zeros of  
>> one function.
>> I would want to write a code using the software R.
>> I have already read the book "Computing the Zeros of Analytic  
>> Functions" (P. Kravanja and M. Van Barel, 2000) that speaks about  
>> this problem, computing a Fortran 90 code.
>> Consequently, I would want to ask You if:
>> - already exists a R code,
>
> I presume you mean analytic functions of a complex argument.  Few R
> packages use complex vectors, and none of those few do this to my
> knowledge.
>

If iterative methods are appropriate,
it's perhaps worth pointing out that Newton-Rapheson
works nicely for complex functions.

The "elliptic" package includes function newton.rapheson()
for this, in addition to other utilities for analyzing
complex functions.


HTH




--
Robin Hankin
Uncertainty Analyst
National Oceanography Centre, Southampton
European Way, Southampton SO14 3ZH, UK
  tel  023-8059-7743