wavethresh (version 4.6.1)

support: Returns support of compactly supported wavelets.

Description

Returns the support for compactly supported wavelets. This information is useful for drawing wavelets for annotating axes.

Usage

support(filter.number=10, family="DaubLeAsymm", m=0, n=0)

Arguments

filter.number

The member index of a wavelet within the family. For Daubechies' compactly supported wavelet this is the number of vanishing moments which is related to the smoothness. See filter.select for more i

family

The family of wavelets. See filter.select for more information on the wavelets.

m

Optional scale value (in usual wavelet terminology this is j)

n

Optional translation value (in usual wavelet terminology, this is k)

Value

• A list with the following components (each one is a single numeric value)
• lh
  Left hand support of the wavelet with scale m and translation n. These values change as m and n (although when m=0 the function confusingly returns the next coarser wavelet where you might expect it to return the mother. The mother is indexed by m=-1)
• rh
  As lh but returns the rh end.
• psi.lh
  left hand end of the support interval for the mother wavelet (remains unchanged no matter what m or n are)
• psi.rh
  right hand end of the support interval for the mother wavelet (remains unchanged no matter what m or n are)
• phi.lh
  left hand end of the support interval for the father wavelet (remains unchanged no matter what m or n are)
• phi.rh
  right hand end of the support interval for the father wavelet (remains unchanged no matter what m or n are)

Details

It is useful to know the support of a wavelet when drawing it to annotate labels. Other functions, such as wavelet density estimation (CWavDE), also use this information.

See Also

CWavDE, draw.default, filter.select

Examples

#
# What is the support of a Haar wavelet?
#
support(filter.number=1, family="DaubExPhase", m=0, n=0)
#$lh
#[1] 0
#
#$rh
#[1] 2
#
#$psi.lh
#[1] 0
#
#$psi.rh
#[1] 1
#
#$phi.lh
#[1] 0
#
#$phi.rh
#[1] 1
#
# So the mother and father wavelet have support [0,1]
#