[R] problems with nonlinear fits using nls

[Gabor Grothendieck]

Corey Bradshaw <corey.bradshaw <at> cdu.edu.au> writes:
 
: I am attempting to determine the nonlinear least-squares estimates of
: the nonlinear model parameters using nls. I have come across a common
: problem that R users have reported when I attempt to fit a particular
: 3-parameter nonlinear function to my dataset:
: 
: Error in nls(r ~ tlm(a, N.fix, k, theta), data = tlm.data, start =
: list(a = a.st,  : 

Try it with nlm.  I find I often have better luck that with it.