rmutil (version 1.1.4)

FormulaMethods: Methods for formulafn Functions

Description

Methods for accessing the contents of a function created from formula produced by finterp or a function modified by fnenvir.

covariates: extract the names of the covariates.

formula: extract the formula used to produce the function (finterp only).

model: extract the model function or model matrix if W&R notation was used.

parameters: extract the names of the parameters.

Usage

# S3 method for formulafn
covariates(z, ...)
# S3 method for formulafn
formula(x, ...)
model(z, ...)
parameters(z, ...)
# S3 method for formulafn
print(x, ...)

Arguments

x,z

A function of class, formulafn.

...

Arguments to other functions.

Value

These methods extract information about functions of class, formulafn, created by finterp or fnenvir.

See Also

finterp, fnenvir.

Examples

# NOT RUN {
x1 <- rpois(20,2)
x2 <- rnorm(20)
#
# Wilkinson and Rogers formula with three parameters
fn1 <- finterp(~x1+x2)
fn1
covariates(fn1)
formula(fn1)
model(fn1)
parameters(fn1)
#
# nonlinear formula with unknowns
fn2 <- finterp(~exp(b0+b1*x1+b2*x2))
fn2
covariates(fn2)
formula(fn2)
model(fn2)
parameters(fn2)
#
# function transformed by fnenvir
fn3 <- fnenvir(function(p) p[1]+p[2]*x1)
covariates(fn3)
formula(fn3)
model(fn3)
parameters(fn3)
# }