wr {rmutil} | R Documentation |

## Find the Response Vector and Design Matrix for a W&R Model Formula

### Description

`wr`

gives the response vector and design matrix for a formula in
Wilkinson and Rogers notation.

### Usage

wr(formula, data=NULL, expand=T)

### Arguments

`formula` |
A model formula. |

`data` |
A data object or environment. |

`expand` |
If FALSE, the covariates are read from the `tccov`
object without expanding to the length of the response variable. |

### Value

`wr`

returns a list containing the response vector
(`z$response`

), if included in the formula, and the design matrix
(`z$design`

) from the data object or environment supplied or from
the global environment for the formula supplied.

### Author(s)

J.K. Lindsey

### Examples

y <- rnorm(20)
x <- gl(4,5)
z <- rpois(20,2)
wr(y~x+z)

[Package

*rmutil* version 1.0

Index]