wavethresh: plot.imwd – R documentation

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plot.imwd

Draw a picture of the 2D wavelet coefficients using image

Description

This function images 2D the absolute values discrete wavelet transform coefficients arising from a imwd.object object.

Usage

## S3 method for class 'imwd'
plot(x, scaling = "by.level", co.type = "abs",
	package = "R", plot.type = "mallat", arrangement = c(3, 3),
	transform = FALSE, tfunction = sqrt, ...)
## S3 method for class 'imwdc'
plot(x, verbose=FALSE, ...)

Arguments

`x`	The 2D imwd object you wish to depict
`scaling`	How coefficient scaling is performed. The options are `by.level` to scale the coefficients independently by level, anything else causes coefficients to be scaled globally
`co.type`	Can be `"abs"` for the absolute values of the coefficients to be plotted, can be `"mabs"` for the negative absolute values or `"none"` for none of this.
`package`	Can be `"R"` for the R package, or `"S"`. The latter does less interesting things and results in a simpler plot
`plot.type`	If this argument is `"mallat"` the coefficients at different scales and orientations are packed into one image and plotted, a format originating from Mallat's early papers on this. The other possibility is `"cols"` which plots each combination of scale and direction on a separate plot. This latter format is useful for examining coefficients, especially at the coarser scales.
`arrangement`	If `plot.type="cols"` then this argument specifies how many rows and columns there are in the plot array.
`transform`	If FALSE then the coefficients are plotted as they are (subject to the `co.type` argument above), if TRUE then the transform function supplied by `tfunction` is applied to the coefficients.
`tfunction`	If `transform=TRUE` then this function gets applied to transform the coefficients before plotting
`verbose`	Print out informative messages
`...`	Supply other arguments to the call to the `image` function. This is very useful to, e.g., can the colours, or other aspects of the image

Details

Description says all

Value

If the package="S" argument is set then a matrix is returned containing the image that would have been plotted (and this only works if the plot.type="mallat" argument is set also.

Author(s)

G P Nason

Examples

data(lennon)
lwd <- imwd(lennon)
## Not run: plot(lwd)
## Not run: plot(lwd, col=grey(seq(from=0, to=1, length=100)), transform=TRUE)

wavethresh

Wavelets Statistics and Transforms

v4.6.8

GPL (>= 2)

Authors

Guy Nason [aut, cre]

Initial release

2016-10-18