if groups is missing, it returns the Dim attribute of
object; otherwise, calculates the dimensions associated with
the grouping factor.
Usage
# S3 method for corStruct
Dim(object, groups, …)
Arguments
object
an object inheriting from class "corStruct",
representing a correlation structure.
groups
an optional factor defining the grouping of the
observations; observations within a group are correlated and
observations in different groups are uncorrelated.
…
some methods for this generic require additional
arguments. None are used in this method.
Value
a list with components:
N
length of groups
M
number of groups
maxLen
maximum number of observations in a group
sumLenSq
sum of the squares of the number of observations per
group
len
an integer vector with the number of observations per
group
start
an integer vector with the starting position for the
observations in each group, beginning from zero