nlme (version 3.1-13)

formula.pdMat: Extract pdMat Formula

Description

This method function extracts the formula associated with a pdMat object, in which the column and row names are specified.

Usage

formula(object)

Arguments

object

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

Value

• if object has a formula attribute, its value is returned, else NULL is returned.

See Also

pdMat

Examples

pd1 <- pdSymm(~Sex*age)
formula(pd1)