Extract pdBlocked Formula

DESCRIPTION:

The formula attributes of the pdMat elements of object are extracted and returned as a list, in case asList=TRUE , or converted to a single one-sided formula when asList=FALSE . If the pdMat elements do not have a formula attribute, a NULL value is returned.

USAGE:

formula(object, asList) 

REQUIRED ARGUMENTS:

object
an object inheriting from class pdBlocked, representing a positive definite block diagonal matrix.

OPTIONAL ARGUMENTS:

asList
an optional logical value. If TRUE, a list with the formulas for the individual block diagonal elements of object is returned; else, if FALSE, a one-sided formula combining all individual formulas is returned. Defaults to FALSE.

VALUE:

a list of one-sided formulas, or a single one-sided formula, or NULL .

SEE ALSO:

,

EXAMPLES:

pd1 <- pdBlocked(list(~ age, ~ Sex - 1)) 
formula(pd1) 
formula(pd1, asList = TRUE)