is.formula

<p>Is a formula?
Checks if argument is a formula</p>

internal

A set of tools that solves a common set of problems: you
need to break a big problem down into manageable pieces, operate on each
piece and then put all the pieces back together.  For example, you might
want to fit a model to each spatial location or time point in your study,
summarise data by panels or collapse high-dimensional arrays to simpler
summary statistics. The development of 'plyr' has been generously supported
by 'Becton Dickinson'.

Hadley Wickham

is.formula: Is a formula? Checks if argument is a formula

Description

Usage

Arguments