.\" -*- nroff -*- generated from .Rd format
.BG
.FN pdBlocked
.TL
Positive-Definite Block Diagonal Matrix
.DN
This function is a constructor for the `pdBlocked' class,
representing a positive-definite block-diagonal matrix. Each
block-diagonal element of the underlying  matrix is itself a
positive-definite matrix and is represented internally as an
individual `pdMat' object. When `value' is
`numeric(0)', a list of uninitialized `pdMat' objects, a
list of one-sided formulas, or a list of vectors 
of character strings,  `object' is returned
as an uninitialized `pdBlocked' object (with just some of its
attributes and its class defined) and needs to have its coefficients
assigned later, generally using the `coef' or {matrix}
functions. If `value' is a list of  initialized `pdMat'
objects, `object' will be constructed from the list obtained by
applying `as.matrix' to each of the `pdMat' elements of
`value'. Finally, if `value' is a list of numeric vectors,
they are assumed to represent the unrestricted coefficients
of the block-diagonal elements of the  underlying positive-definite
matrix.
.CS
pdBlocked(value, form, nam, data, pdClass)
.OA
.AG value
an optional list with elements to be used as the
`value' argument to other `pdMat' constructors. These
include: `pdMat' objects, positive-definite
matrices, one-sided linear formulas, vectors of character strings, or
numeric vectors. All elements in the list must be similar (e.g. all
one-sided formulas, or all numeric vectors). Defaults to
`numeric(0)', corresponding to an uninitialized object.
.AG form
an optional list of one-sided linear formulas specifying the
row/column names for the block-diagonal elements of the matrix
represented by `object'. Because factors may be present in
`form', the formulas needs to be evaluated on a data.frame to
resolve the names they define. This argument is ignored when
`value' is a list of one-sided formulas. Defaults to `NULL'.
.AG nam
an optional list of vector of character strings specifying the
row/column names for the block-diagonal elements of the matrix
represented by object. Each of its components must have  
length equal to the dimension of the corresponding block-diagonal
element and unreplicated elements. This argument is ignored when 
`value' is a list of vector of character strings. Defaults to 
`NULL'.
.AG data
an optional data frame in which to evaluate the variables
named in `value' and `form'. It is used to
obtain the levels for `factors', which affect the
dimensions and the row/column names of the underlying matrix. If
`NULL', no attempt is made to obtain information on any
`factors' appearing in the formulas. Defaults to the parent
frame from which the function was called.
.AG pdClass
an optional vector of character strings naming the
`pdMat' classes to be assigned to the individual blocks in the
underlying matrix. If a single class is specified, it is used for all
block-diagonal elements. This argument will only be used when
`value' is missing, or its elements are not `pdMat'
objects. Defaults to `"pdSymm"'.
.RT
a `pdBlocked' object representing a positive-definite
block-diagonal matrix, also inheriting from class `pdMat'.

.SA
`as.matrix.pdMat', `coef.pdMat',
`matrix<-.pdMat'
.EX
pd1 <- pdBlocked(list(diag(1:2), diag(c(0.1, 0.2, 0.3))),
                 nam = list(c("A","B"), c("a1", "a2", "a3")))
pd1
.KW models
.WR
