wmtsa (version 2.0-2)

wavTransform: Constructor function for objects of class wavTransform

Description

Packs input information regarding a discrete wavelet transform into a list.

Usage

wavTransform(data, series, n.levels, dictionary, shifted, xform)

Arguments

data

a list of vectors containing discrete wavelet transform coefficients.

series

a numeric vector or signalSeries object representing the input series.

n.levels

an integer denoting the number of decomposition levels.

dictionary

an object of class wavDictionary representing the wavelet dictionary of the transform.

shifted

a logical value. If TRUE, it signifies that the transform coefficients have already been shifted for approximate zero phase alignment.

xform

a character string denoting the type of wavelet transform that has been performed. Typical values are "modwt" or "dwt".

Value

an object of class wavTransform.

S3 METHODS

[

single level data access. Usage: x["d2"] or x[2] Access a subset of wavelet transform crystals.

[<-

single level data replacement method. Usage: x["d2"] <- 1:4 Replace an entire crystal with explicitly defined coefficients.

[[

double level data access. Usage: x[["d2"]] or x[[2]] Returns a vector of transform coefficients corresponding to the specified crystal.

as.matrix

transforms the list of wavelet transform coefficients into a single-column matrix whose row names identify the transform coefficient, e.g., d4(3) is the third coefficient of the d4 crystal (fourth level wavelet coefficients). Usage: as.matrix(x)

boxplot

plots a boxplot for each crystal in the discrete wavelet transform. Usage: boxplot(x)

eda.plot

extended data analysis plot. A 2x2 grid of plots containing a stack plot, boxplot, and two energy related plots are shown. Usage: eda.plot(x)

plot

plot a discrete wavelet transform. Usage: plot(x, type="h", plot.bar=TRUE, plot.pie=TRUE, add=FALSE, cex.main=ifelse1(is.R(),1,0.7), ...)

x

A wavTransform object.

type

A character denoting the type of line plot to produce in a stack plot of the wavelet transform coefficients (see primary plot() function for details). If type is the character string "energy" an energy plot (bar or pie chart) is produced. Default: "h".

plot.bar

A logical value. If TRUE and type="energy", a bar plot of crystal energy is plotted. Default: TRUE.

plot.pie

A logical value. If TRUE and type="energy", a pie chart of crystal energy is plotted. Default: FALSE.

add

A logical value. If TRUE, the plot is added to the current plot layout without a frame ejection. Default: FALSE.

...

Additional arguments to be sent to the stackplot routine.

print

print the wavelet transform object. Usage: print(x)

reconstruct

reconstruct/synthesize/invert the wavelet transform. Usage: reconstruct(x) If the transform coefficients were not modified, the original time series will be returned (+/- some numerical noise).

summary

provide a statistical summary of the wavelet transform object. Usage: z <- summary(x); print(z)

wavStackPlot

stack plot of the wavelet transform. Usage: wavStackPlot(x)

Details

Used internally by the wavMODWT and wavDWT functions to package the transform contents into a list.

See Also

wavDWT, wavMODWT, wavDWPT, wavMODWPT, wavBoundary, wavSortCrystals, wavPacketIndices, wavShrink.

Examples

## calculate a MODWT of the sunpots series and 
## verify the class 
W <- wavMODWT(sunspots)
print(class(W))

## summarize the object 
summary(W)

## reconstruct the MODWT of the sunspots series 
## and compare to the original 
sunup <- reconstruct(W)
splus2R::vecnorm(sunup - sunspots)