R: Register Functional Data Objects with Pre-Computed Warping...

register.newfd {fda} | R Documentation

## Register Functional Data Objects with Pre-Computed Warping Functions

### Description

This function registers a new functional data object to pre-computed warping functions.

### Usage

    register.newfd(yfd, Wfd,type=c('direct','monotone','periodic'))

### Arguments

`yfd` | a multivariate functional data object defining the functions to be registered with `Wfd`.
`Wfd` | a functional data object defining the registration functions to be used to register `yfd`. This can be the result of either `landmarkreg` or `register.fd`.
`type` | indicates the type of registration function. direct assumes `Wfd` is a direct definition of the registration functions. This is produced by `landmarkreg`. monotone assumes that `Wfd` defines a monotone functional data objected, up to shifting and scaling to make endpoints agree. This is produced by `register.fd`. periodic does shift registration for periodic functions. This is output from `register.fd` if `periodic=TRUE`.

### Details

Only shift registration is considered for the periodic case.

### Value

a functional data object defining the registered curves.

### Source

Ramsay, James O., and Silverman, Bernard W. (2006), Functional Data Analysis, 2nd ed., Springer, New York.

Ramsay, James O., and Silverman, Bernard W. (2002), Applied Functional Data Analysis, Springer, New York, ch. 6 & 7.

### See Also

`landmarkreg`, `register.fd`

### Examples

    # Register the lip data with landmark registration, then register the first
    # derivatives with the pre-computed warping functions.

    # Lip data:
    lipfd <- smooth.basisPar(liptime, lip, 6, Lfdobj=int2Lfd(4),
                             lambda=1e-12)$fd
    names(lipfd$fdnames) <- c("time(seconds)", "replications", "mm")

    # Landmark Registration:

    lipmeanmarks <- apply(lipmarks,2,mean)

    wnbasis <- 6
    wnorder <- 4
    wbreaks <- c(0,lipmeanmarks,0.35)

    warpbasis <- create.bspline.basis(nbasis=wnbasis, norder=wnorder,
                                      breaks=wbreaks);
    WfdPar    <- fdPar(fd(basisobj=warpbasis), 2, 1e-4)

    lipreglist <- landmarkreg(lipfd, as.matrix(lipmarks), lipmeanmarks, WfdPar)

    # And warp:

    Dlipfd = deriv.fd(lipfd,Lfdobj=1)

    Dlipregfd = register.newfd(Dlipfd,lipreglist$warpfd,type='direct')

[Package fda version 2.4.8 Index]