model.matrix.gam            package: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)

