Generate a model environment from a classical formula based interface.
A flexible implementation of the classical formula based interface.
ModelEnvFormula(formula, data = list(), subset = NULL,
na.action = NULL, frame = NULL,
enclos = sys.frame(sys.nframe()), other = list(),
designMatrix = TRUE, responseMatrix = TRUE,
setHook = NULL, ...)formula |
a symbolic description of the model to be fit. |
data |
an optional data frame containing the variables in the model.
If not found in |
subset |
an optional vector specifying a subset of observations to be used in the fitting process. |
na.action |
a function which indicates what should happen when the data
contain |
frame |
an optional environment |
enclos |
specifies the enclosure passed to |
other |
an optional named list of additional formulae. |
designMatrix |
a logical indicating whether the design matrix
defined by the right hand side of |
responseMatrix |
a logical indicating whether the design matrix
defined by the left hand side of |
setHook |
a list of functions to |
... |
additional arguments for be passed to function, for example
|
This function is an attempt to provide a flexible infrastucture for the
implementation of classical formula based interfaces. The arguments
formula, data, subset and na.action are well
known and are defined in the same way as in lm, for example.
ModelEnvFormula returns an object of class
ModelEnvFormula-class - a high level object for storing
data improving upon the capabilities of data.frames.
An object of class ModelEnvFormula-class.
### the `usual' interface
data(iris)
mf <- ModelEnvFormula(Species ~ ., data = iris)
mf
### extract data from the ModelEnv object
summary(mf@get("response"))
summary(mf@get("input"))
dim(mf@get("designMatrix"))
### contrasts
mf <- ModelEnvFormula(Petal.Width ~ Species, data = iris,
contrasts.arg = list(Species = contr.treatment))
attr(mf@get("designMatrix"), "contrasts")
mf <- ModelEnvFormula(Petal.Width ~ Species, data = iris,
contrasts.arg = list(Species = contr.sum))
attr(mf@get("designMatrix"), "contrasts")
### additional formulae
mf <- ModelEnvFormula(Petal.Width ~ Species, data = iris,
other = list(pl = ~ Petal.Length))
ls(mf@env)
identical(mf@get("pl")[[1]], iris[["Petal.Length"]])Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.