Dim.corStruct {nlme} | R Documentation |

## 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)

Jose Pinheiro Jose.Pinheiro@pharma.novartis.com and Douglas Bates bates@stat.wisc.edu

### See Also

`Dim`

, `Dim.corSpatial`

### Examples

Dim(corAR1(), getGroups(Orthodont))

[Package

*nlme* version 3.1-80

Index]