formula.pdBlocked {nlme}R Documentation

Extract pdBlocked Formula


The formula attributes of the pdMat elements of x 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.


## S3 method for class 'pdBlocked':
formula(x, asList, ...)


x an object inheriting from class pdBlocked, representing a positive definite block diagonal matrix.
asList an optional logical value. If TRUE, a list with the formulas for the individual block diagonal elements of x is returned; else, if FALSE, a one-sided formula combining all individual formulas is returned. Defaults to FALSE.
... some methods for this generic require additional arguments. None are used in this method.


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


Jose Pinheiro and Douglas Bates

See Also

pdBlocked, pdMat


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

[Package nlme version 3.1-57 Index]