coef.corStruct             package:nlme             R Documentation

Coefficients of a corStruct Object

Description:

     This method function extracts the coefficients associated with the
     correlation structure represented by 'object'.

Usage:

     ## S3 method for class 'corStruct':
     coef(object, unconstrained, ...)
     ## S3 replacement method for class 'corStruct':
     coef(object, ...) <- value

Arguments:

  object: an object inheriting from class 'corStruct', representing a
          correlation structure.

unconstrained: a logical value. If 'TRUE' the coefficients are returned
          in unconstrained form (the same used in the optimization
          algorithm). If 'FALSE' the coefficients are returned in
          "natural", possibly constrained, form. Defaults to 'TRUE'.

   value: a vector with the replacement values for the coefficients
          associated with 'object'. It must be a vector with the same
          length of 'coef{object}' and must be given in unconstrained
          form.

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

Value:

     a vector with the coefficients corresponding to 'object'.

SIDE EFFECTS:

     On the left side of an assignment, sets the values of the
     coefficients of 'object' to 'value'. 'Object' must be initialized
     (using 'Initialize') before new values can be assigned to its
     coefficients.

Author(s):

     Jose Pinheiro and Douglas Bates

References:

     Pinheiro, J. C. and Bates, D. M. (2000), _Mixed-Effects Models in
     S and S-PLUS_, Springer, New York.

See Also:

     'corAR1', 'corARMA', 'corCAR1', 'corCompSymm', 'corExp',
     'corGaus', 'corLin', 'corRatio', 'corSpatial', 'corSpher',
     'corSymm','Initialize'

Examples:

     cst1 <- corARMA(p = 1, q = 1)
     coef(cst1)

