pdMat {nlme} | R Documentation |
Positive-Definite Matrix
Description
This function gives an alternative way of constructing an object
inheriting from the pdMat
class named in pdClass
, or
from data.class(object)
if object
inherits from
pdMat
, and is mostly used internally in other functions. See
the documentation on the principal constructor function, generally
with the same name as the pdMat
class of object.
Usage
pdMat(value, form, nam, data, pdClass)
Arguments
value |
an optional initialization value, which can be any of the
following: a |
form |
an optional one-sided linear formula specifying the
row/column names for the matrix represented by |
nam |
an optional vector of character strings specifying the
row/column names for the matrix represented by object. It must have
length equal to the dimension of the underlying positive-definite
matrix and unreplicated elements. This argument is ignored when
|
data |
an optional data frame in which to evaluate the variables
named in |
pdClass |
an optional character string naming the
|
Value
a pdMat
object representing a positive-definite matrix,
inheriting from the class named in pdClass
, or from
class(object)
, if object
inherits from pdMat
.
Author(s)
José Pinheiro and Douglas Bates bates@stat.wisc.edu
References
Pinheiro, J.C., and Bates, D.M. (2000) "Mixed-Effects Models in S and S-PLUS", Springer.
See Also
pdClasses
,
pdCompSymm
, pdDiag
,
pdIdent
, pdNatural
,
pdSymm
,
reStruct
,
solve.pdMat
,
summary.pdMat
Examples
pd1 <- pdMat(diag(1:4), pdClass = "pdDiag")
pd1
str(pd1)