fd {fda}R Documentation

Define a Functional Data Object

Description

This is the constructor function for objects of the fd class. Each function that sets up an object of this class must call this function. This includes functions data2fd, smooth.basis, density.fd, and so forth that estimate functional data objects that smooth or otherwise represent data. Ordinarily, user of the functional data analysis software will not need to call this function directly, but these notes are valuable to understanding what the "slots" or "members" of the fd class are.

Usage

fd(coef=matrix(0, 2, 1), basisobj=basisfd(),
   fdnames=defaultnames)

Arguments

coef a vector, matrix, or three-dimensional array of coefficients. The first dimension of matrices and arrays, as well as that of a vector, is corresponds to basis functions. The second dimension corresponds to the number of functions or curves, or to replicates. The third dimension if present corresponds to variables for multivariate functional data objects. A functional data object is referred to as "univariate" if this argument is a vector or a matrix, and "multivariate" if it is a three-dimensional array.
basisobj a functional basis object defining the basis
fdnames A list of length 3, each member being a string vector containing labels for the levels of the corresponding dimension of the discrete data. The first dimension is for argument values, and is given the default name "time", the second is for replications, and is given the default name "reps", and the third is for functions, and is given the default name "values".

Details

To check that an object is of this class, use function is.fd.

Normally only developers of new functional data analysis functions will actually need to use this function, so no examples are provided.

Value

a functional data object

See Also

Most of the functional data analysis functions either have functional data objects as arguments, or generate functional data objects, or both.


[Package fda version 1.1.2 Index]