object
.
coef(object, unconstrained) coef(object) <- value
pdMat
,
representing a positive-definite matrix.
TRUE
the coefficients
are returned in unconstrained form (the same used in the optimization
algorithm). If
FALSE
the upper triangular elements of the
positive-definite matrix represented by
object
are
returned. Defaults to
TRUE
.
object
. It must be a vector with the same length
of `coef{object}' and must be given in unconstrained form.
object
.
On the left side of an assignment, sets the values of the coefficients
of
object
to
value
.
Pinheiro, J.C. and Bates., D.M. (1996) "Unconstrained Parametrizations for Variance-Covariance Matrices", Statistics and Computing, 6, 289-296.
coef(pdSymm(diag(3)))