nls.control {stats}  R Documentation 
Allow the user to set some characteristics of the nls
nonlinear least squares algorithm.
nls.control(maxiter = 50, tol = 1e05, minFactor = 1/1024, printEval = FALSE, warnOnly = FALSE)
maxiter 
A positive integer specifying the maximum number of iterations allowed. 
tol 
A positive numeric value specifying the tolerance level for the relative offset convergence criterion. 
minFactor 
A positive numeric value specifying the minimum stepsize factor allowed on any step in the iteration. The increment is calculated with a GaussNewton algorithm and successively halved until the residual sum of squares has been decreased or until the stepsize factor has been reduced below this limit. 
printEval 
a logical specifying whether the number of evaluations (steps in the gradient direction taken each iteration) is printed. 
warnOnly 
a logical specifying whether nls() should
return instead of signalling an error in the case of termination
before convergence.
Termination before convergence happens upon completion of maxiter
iterations, in the case of a singular gradient, and in the case that the
stepsize factor is reduced below minFactor . 
A list
with exactly five components:
maxiter 

tol 

minFactor 

printEval 

warnOnly 
with meanings as explained under ‘Arguments’.
Douglas Bates and Saikat DebRoy
Bates and Watts (1988), Nonlinear Regression Analysis and Its Applications, Wiley.
nls.control(minFactor = 1/2048)