From: Borries Demeler <demeler@bioc09.v19.uthscsa.edu>
  To  : Daniel Ryan <drya9411@mail.usyd.edu.au>
  Date: Wed, 18 Oct 2000 17:35:09 -0500 (CDT)

Re: HELP!

Dear Daniel,

Since i have written such programs myself - I can assure you that writing
the NLS stuff is the easy part. The complication comes in designing a 
functional and general interface that will work with the NLS algorithm
in such a way that the user finds it intuitive and easy to use. What
variables stay local/global, how to present it to the user and to 
put in all the necessary error checks to prevent the user from 
making any fundamental errors. By no means do I want to discourage you,
just be sure that you realize that the NLS algorithm is the least of 
your worries there, that stuff is straightforward and you can find it
documented in many public domain sources, netlib is probably your best
source or some of the weblinks I pointed out before to you. But to my 
knowledge, a truly general global fitter has not been developed yet
(I am working on it since I need it myself :-).

Good luck, -Borries