InvBasis.wst: Invert a wst library representation with a basis...

In wavethresh: Wavelets Statistics and Transforms

Invert a wst library representation with a basis specification

Description

Inverts a wst basis representation with a given basis specification, for example an output from the MaNoVe function.

Usage

## S3 method for class 'wst'
InvBasis(wst, nv, ...)

Arguments

wst	The wst object that you wish to invert
nv	The node vector, basis spec, that you want to pick out
...	Other arguments, that don't do anything here

Details

Objects arising from a wst.object specification are a representation of a signal with respect to a library of basis functions. A particular basis specification can be obtained using the numtonv function which can pick an indexed basis function, or MaNoVe.wst which uses the Coifman-Wickerhauser minimum entropy method to select a basis. This function takes a wst.object and a particular basis description (in a nv.object node vector object) and inverts the representation with respect to that selected basis.

Value

The inverted reconstruction

Author(s)

G P Nason

See Also

numtonv,nv.object,MaNoVe.wst,threshold.wst,wst

Examples

#
# Let's generate a noisy signal
#
x <- example.1()$y + rnorm(512, sd=0.2)
#
# You can plot this if you like
#
## Not run: ts.plot(x)
#
# Now take the nondecimated wavelet transform
#
xwst <- wst(x)
#
# Threshold it
#
xwstT <- threshold(xwst)
#
# You can plot this too if you like
#
## Not run: plot(xwstT)
#
# Now use Coifman-Wickerhauser to get a "good" basis
#
xwstTNV <- MaNoVe(xwstT)
#
# Now invert the thresholded wst using this basis specification
#
xTwr <- InvBasis(xwstT, xwstTNV)
#
# And plot the result, and superimpose the truth in dotted
#
## Not run: ts.plot(xTwr)
## Not run: lines(example.1()$y, lty=2)

wavethresh documentation built on Sept. 11, 2024, 9:33 p.m.