R: Values a Two-argument Functional Data Object

eval.bifd {fda} | R Documentation

## Values a Two-argument Functional Data Object

### Description

A vector of argument values for the first argument `s` of the functional data object to be evaluated.

### Usage

    eval.bifd(sevalarg, tevalarg, bifd, sLfdobj=0, tLfdobj=0,
              returnMatrix=FALSE)

### Arguments

`sevalarg` | a vector of argument values for the first argument `s` of the functional data object to be evaluated.
`tevalarg` | a vector of argument values for the second argument `t` of the functional data object to be evaluated.
`bifd` | a two-argument functional data object.
`sLfdobj` | either a nonnegative integer or a linear differential operator object. If present, the derivative or the value of applying the operator to the object as a function of the first argument `s` is evaluated rather than the functions themselves.
`tLfdobj` | either a nonnegative integer or a linear differential operator object. If present, the derivative or the value of applying the operator to the object as a function of the second argument `t` is evaluated rather than the functions themselves.
`returnMatrix` | logical: If TRUE, a two-dimensional is returned using a special class from the Matrix package.

### Value

an array of 2, 3, or 4 dimensions containing the function values. The first dimension corresponds to the argument values in sevalarg, the second to argument values in tevalarg, the third if present to replications, and the fourth if present to functions.

### Examples

    # every-other-day basis to save test time
    daybasis   <- create.fourier.basis(c(0,365), 183)
    harmLcoef  <- c(0,(2*pi/365)^2,0)
    harmLfd    <- vec2Lfd(harmLcoef, c(0,365))
    templambda <- 1.0
    tempfdPar  <- fdPar(daybasis, harmLfd, lambda=1)
    tempfd     <- smooth.basis(day.5,
              CanadianWeather$dailyAv[,,"Temperature.C"], tempfdPar)$fd
    #    define the variance-covariance bivariate fd object
    tempvarbifd <- var.fd(tempfd)
    #    evaluate the variance-covariance surface and plot
    weektime    <- seq(0,365,len=53)
    tempvarmat  <- eval.bifd(weektime,weektime,tempvarbifd)
    #    make a perspective plot of the variance function
    persp(tempvarmat)

[Package fda version 2.4.8 Index]