logDet.pdMat              package:nlme              R Documentation

Extract Log-Determinant from a pdMat Object

Description:

     This method function extracts the logarithm of the determinant of
     a square-root factor of the positive-definite matrix represented
     by 'object'.

Usage:

     ## S3 method for class 'pdMat':
     logDet(object, ...)

Arguments:

  object: an object inheriting from class 'pdMat', representing a
          positive definite matrix.

     ...: some methods for this generic require additional arguments. 
          None are used in this method.

Value:

     the log-determinant of a square-root factor of the
     positive-definite matrix represented by 'object'.

Author(s):

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

See Also:

     'pdMat'

Examples:

     pd1 <- pdSymm(diag(1:3))
     logDet(pd1)

