Dim.corStruct {nlme}

Dimensions of a corStruct Object

Description

if groups is missing, it returns the Dim attribute of object; otherwise, calculates the dimensions associated with the grouping factor.

Usage

## S3 method for class '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

Author(s)

José Pinheiro and Douglas Bates [e-mail]

See Also

Dim, Dim.corSpatial

Examples

Dim(corAR1(), getGroups(Orthodont))