R: Extract model matrix from GAM fit

model.matrix.gam {mgcv} | R Documentation

## Extract model matrix from GAM fit

### Description

Obtains the model matrix from a fitted `gam` object.

### Usage

    ## S3 method for class 'gam'
    model.matrix(object, ...)

### Arguments

`object` | fitted model object of class `gam` as produced by `gam()`.
`...` | other arguments, passed to `predict.gam`.

### Details

Calls `predict.gam` with no `newdata` argument and `type="lpmatrix"` in order to obtain the model matrix of `object`.

### Value

A model matrix.

### Author(s)

Simon N. Wood simon.wood@r-project.org

### References

Wood S.N. (2006b) Generalized Additive Models: An Introduction with R. Chapman and Hall/CRC Press.

### See Also

`gam`

### Examples

    n <- 15
    x <- runif(n)
    y <- sin(x*2*pi) + rnorm(n)*.2
    mod <- gam(y~s(x,bs="cc",k=6),knots=list(x=seq(0,1,length=6)))
    model.matrix(mod)

[Package mgcv version 1.7-18 Index]