WaveThresh Help - putD

Put wavelet coefficients into wavelet structure

DESCRIPTION:

Makes a copy of the wd object, replaces some wavelet coefficients into the copy, and then returns the copy.

USAGE:

putD(wd, level, v, boundary=F)

REQUIRED ARGUMENTS:

wd: wd class object that is to be copied, have wavelet coefficients replaced and then returned.
level: The level at which replacement is to take place.
v: The replacement coefficients, this should be of the correct length.

OPTIONAL ARGUMENTS:

boundary

If boundary is F then only the "real" coefficients are replaced (and it is easy to predict the required length of the v, just the correct power of 2). If boundary=T then you can replace the boundary coefficients as well (but it is hard to predict the required length of v, and the information has to be extracted from the first.last database component of wd).

This argument has no meaning if the wd object was obtained using periodic boundary handling.

VALUE:

A wd class object containing the replaced data.

SIDE EFFECTS:

None

DETAILS:

The function "accessD" obtains the wavelet coefficients for a particular level. The function "putD" replaces coefficients at a particular level and returns a modified wd object reflecting the change.

As opposed to the utility of "putC", the "putD" function is actually quite useful. It is fun to replace coefficients, since then you can dream up your own functions, get pictures of the wavelets etc. etc.

RELEASE:

EXAMPLES:

#
# Set all the wavelet coefficients to zero
#
> for(i in 0:(wd$nlevels-1))
      wd <- putD(wd, level=i, v=rep(0,2^i))

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G.P.Nason@bristol.ac.uk