A tidy basis representation of a smooth object

Takes an object of class mgcv.smooth and returns a tidy representation of the basis.

Usage

tidy_basis(
  smooth,
  data = NULL,
  at = NULL,
  coefs = NULL,
  p_ident = NULL,
  envir = NULL
)

Arguments

smooth

a smooth object of or inheriting from class "mgcv.smooth". Typically, such objects are returned as part of a fitted GAM or GAMM in the $smooth component of the model object or the $gam$smooth component if the model was fitted by mgcv::gamm() or gamm4::gamm4().

data

a data frame containing the variables used in smooth.

at

a data frame containing values of the smooth covariate(s) at which the basis should be evaluated.

coefs

numeric; an optional vector of coefficients for the smooth

p_ident

retained for compatibility. Fitted SCAM smooths use their stored coefficient constraints to match basis columns to coefficients.

envir

an optional environment supplying functions and constants used in model expressions. The available model formula environment is used when NULL. Covariate observations should be supplied in data.

Value

A tibble.

Author

Gavin L. Simpson

Examples

load_mgcv()
df <- data_sim("eg1", n = 400, seed = 42)

# fit model
m <- gam(y ~ s(x0) + s(x1) + s(x2) + s(x3), data = df, method = "REML")

# tidy representaition of a basis for a smooth definition
# extract the smooth
sm <- get_smooth(m, "s(x2)")
# get the tidy basis - need to pass where we want it to be evaluated
bf <- tidy_basis(sm, at = df)

# can weight the basis by the model coefficients for this smooth
bf <- tidy_basis(sm, at = df, coefs = smooth_coefs(sm, model = m))