nlsList {nlme}  R Documentation 
Data
is partitioned according to the levels of the grouping
factor defined in model
and individual nls
fits are
obtained for each data
partition, using the model defined in
model
.
nlsList(model, data, start, control, level, subset, na.action, pool) ## S3 method for class 'nlsList': update(object, model., ..., evaluate = TRUE)
object 
an object inheriting from class nlsList , representing
a list of fitted nls objects. 
model 
either a nonlinear model formula, with the response on
the left of a ~ operator and an expression involving
parameters, covariates, and a grouping factor separated by the
 operator on the right, or a selfStart function. The
method function nlsList.selfStart is documented separately.

model. 
Changes to the model – see update.formula for
details. 
data 
a data frame in which to interpret the variables named in
model .

start 
an optional named list with initial values for the
parameters to be estimated in model . It is passed as the
start argument to each nls call and is required when
the nonlinear function in model does not inherit from class
selfStart .

control 
a list of control values passed as the control
argument to nls . Defaults to an empty list.

level 
an optional integer specifying the level of grouping to be used when multiple nested levels of grouping are present. 
subset 
an optional expression indicating the subset of the rows of
data that should be used in the fit. This can be a logical
vector, or a numeric vector indicating which observation numbers are
to be included, or a character vector of the row names to be
included. All observations are included by default. 
na.action 
a function that indicates what should happen when the
data contain NA s. The default action (na.fail ) causes
nlsList to print an error message and terminate if there are any
incomplete observations.

pool 
an optional logical value that is preserved as an attribute of the
returned value. This will be used as the default for pool in
calculations of standard deviations or standard errors for summaries.

... 
some methods for this generic require additional arguments. None are used in this method. 
evaluate 
If TRUE evaluate the new call else return the call. 
a list of nls
objects with as many components as the number of
groups defined by the grouping factor. Generic functions such as
coef
, fixed.effects
, lme
, pairs
,
plot
, predict
, random.effects
, summary
,
and update
have methods that can be applied to an nlsList
object.
fm1 < nlsList(uptake ~ SSasympOff(conc, Asym, lrc, c0), data = CO2, start = c(Asym = 30, lrc = 4.5, c0 = 52)) summary(fm1)