pdMat {nlme}  R Documentation 
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.
pdMat(value, form, nam, data, pdClass)
value 
an optional initialization value, which can be any of the
following: a 
form 
an optional onesided 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 positivedefinite
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

a pdMat
object representing a positivedefinite matrix,
inheriting from the class named in pdClass
, or from
class(object)
, if object
inherits from pdMat
.
JosÃ© Pinheiro and Douglas Bates bates@stat.wisc.edu
Pinheiro, J.C., and Bates, D.M. (2000) "MixedEffects Models in S and SPLUS", Springer.
pdClasses
,
pdCompSymm
, pdDiag
,
pdIdent
, pdNatural
,
pdSymm
,
reStruct
,
solve.pdMat
,
summary.pdMat
pd1 < pdMat(diag(1:4), pdClass = "pdDiag") pd1