R: Wavelet Packet decomposition objects.

wp.object {wavethresh} | R Documentation

## Wavelet Packet decomposition objects.

### Description

These are objects of classes `wp` They represent a decomposition of a function with respect to a set of wavelet packet functions.

### Details

To retain your sanity we recommend that wavelet packets be extracted in one of two ways:

- use `getpacket.wp` to obtain individual packets.

- use `accessD.wp` to obtain all coefficients at a particular resolution level.

You can obtain the coefficients directly from the `wp$wp` component but you have to understand their organization described above.

### Value

The following components must be included in a legitimate ‘wp’ object.

`wp` | a matrix containing the wavelet packet coefficients. Each row of the matrix contains coefficients with respect to a particular resolution level. There are `nlevelsWT(wp)+1` rows in the matrix. Row `nlevels(wp)+1` (the “bottom”) row contains the “original” data used to produce the wavelet packet coefficients. Rows `nlevels`(wp) to row 1 contain coefficients at resolution levels `nlevels(wp)-1` to 0 (so the first row contains coefficients at resolution level 0). The columns contain the coefficients with respect to packets. A different packet length exists at each resolution level. The packet length at resolution level `i` is given by `2^i`. However, the `getpacket.wp` function should be used to access individual packets from a `wp` object.
`nlevelsWT` | The number of levels in the wavelet packet decomposition. If you raise 2 to the power of nlevels you get the number of data points used in the decomposition.
`filter` | a list containing the details of the filter that did the decomposition (equivalent to the return value from the `filter.select` function).
`date` | The date that the transform was performed or the wp was modified.

### GENERATION

This class of objects is returned from the `wp` function to represent a wavelet packet decomposition of a function. Many other functions return an object of class wp.

### METHODS

The wp class of objects has methods for the following generic functions: `InvBasis`, `MaNoVe`, `accessC`, `accessD`, `basisplot`, `draw`. `getpacket`, `nlevelsWT`, `plot`, `print`, `putC`, `putD`, `putpacket`, `summary`, `threshold`.

### RELEASE

Version 3.5.3 Copyright Guy Nason 1994

### Author(s)

G P Nason

### See Also

`wp`

[Package wavethresh version 4.6.8 Index]