getGroups.corStruct Extract corStruct Groups
Description
This method function extracts the grouping factor associated with object, if any is present.
Usage
## S3 method for class 'corStruct'
getGroups(object, form, level, data, sep)
Arguments
object |
an object inheriting from class |
form |
this argument is included to make the method function compatible with the generic. It will be assigned the value of |
level |
this argument is included to make the method function compatible with the generic and is not used. |
data |
an optional data frame in which to evaluate the variables defined in |
sep |
character, the separator to use between group levels when multiple levels are collapsed. The default is |
Value
if a grouping factor is present in the correlation structure represented by object, the function returns the corresponding factor vector; else the function returns NULL.
Author(s)
José Pinheiro and Douglas Bates bates@stat.wisc.edu
See Also
Examples
cs1 <- corAR1(form = ~ 1 | Subject)
getGroups(cs1, data = Orthodont)
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Licensed under the GNU General Public License.