| getCovariate.corStruct {nlme} | R Documentation |
This method function extracts the covariate(s) associated with
object.
## S3 method for class 'corStruct': getCovariate(object, form, data)
object |
an object inheriting from class corStruct
representing a correlation structure. |
form |
this argument is included to make the method function
compatible with the generic. It will be assigned the value of
formula(object) and should not be modified. |
data |
an optional data frame in which to evaluate the variables
defined in form, in case object is not initialized and
the covariate needs to be evaluated. |
when the correlation structure does not include a grouping factor, the
returned value will be a vector or a matrix with the covariate(s)
associated with object. If a grouping factor is present, the
returned value will be a list of vectors or matrices with the
covariate(s) corresponding to each grouping level.
Jose Pinheiro Jose.Pinheiro@pharma.novartis.com and Douglas Bates bates@stat.wisc.edu
cs1 <- corAR1(form = ~ 1 | Subject) getCovariate(cs1, data = Orthodont)