| accessC.wst {wavethresh} | R Documentation |
Get smoothed data from packet ordered non-decimated wavelet object (wst)
Description
The smoothed data from a packet ordered non-decimated wavelet object (returned from wst) are stored in a matrix. This function extracts all the coefficients corresponding to a particular resolution level.
Usage
## S3 method for class 'wst'
accessC(wst, level, aspect, ...)
Arguments
wst |
Packet ordered non-decimated wavelet object from which you wish to extract the smoothed or original data (if the object is directly from a packet ordered non-decimated wavelet transform of some data). |
level |
The level that you wish to extract. This can range from zero (the coarsest coefficients) to nlevelsWT(wstobj) which returns the original data. |
aspect |
Applies function to coefficients before return. Supplied as a character string which gets converted to a function. For example "Mod" which returns the absolute values of the coefficients |
... |
Other arguments |
Details
The wst function performs a packet-ordered non-decimated wavelet transform. This function extracts all the father wavelet coefficients at a particular resolution level specified by level.
Note that coefficients returned by this function are in emphpacket order. They can be used as is but for many applications it might be more useful to deal with the coefficients in packets: see the function getpacket.wst for further details.
Value
A vector of the extracted data.
Author(s)
G P Nason
References
Nason, G. P. and Silverman, B. W. (1994). The discrete wavelet transform in S. Journal of Computational and Graphical Statistics, 3, 163–191.
See Also
wst, wst.object, accessC, getpacket.wst
Examples
#
# Get the 3rd level of smoothed data from a decomposition
#
dat <- rnorm(64)
accessC(wst(dat), level=3)