fda (version 6.1.8)

knots.fd: Extract the knots from a function basis or data object

Description

Extract either all or only the interior knots from an object of class basisfd, fd, or fdSmooth.

Usage

# S3 method for fd
knots(Fn, interior=TRUE, ...)
# S3 method for fdSmooth
knots(Fn, interior=TRUE, ...)
# S3 method for basisfd
knots(Fn, interior=TRUE, ...)

Value

Numeric vector. If 'interior' is TRUE, this is the params

component of the bspline basis. Otherwise, params is bracketed by rep(rangeval, norder(basisfd).

Arguments

Fn

an object of class basisfd or containing such an object

interior

logical:

if TRUE, Fn[["params"]] are returned.

Else, nord <- norder(Fn); rng <- Fn[['rangeval']]; return c(rep(rng[1], nord), Fn[["params"]], rep(rng[2], nord))

...

ignored

Author

Spencer Graves

Details

The interior knots of a bspline basis are stored in the params component. The remaining knots are in the rangeval component, with multiplicity norder(Fn).

References

Ramsay, James O., Hooker, Giles, and Graves, Spencer (2009), Functional data analysis with R and Matlab, Springer, New York.

Ramsay, James O., and Silverman, Bernard W. (2005), Functional Data Analysis, 2nd ed., Springer, New York.

Ramsay, James O., and Silverman, Bernard W. (2002), Applied Functional Data Analysis, Springer, New York.

See Also

fd, create.bspline.basis,