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nullevels.wst
Sets whole resolution levels of coefficients equal to zero in a
wst object.
DESCRIPTION
Sets whole resolution levels of coefficients equal to zero in a
wst object.
USAGE
nullevels.wst(wst, levelstonull)
REQUIRED ARGUMENTS
- wst
- An object of class wst.
- levelstonull
- An integer vector specifying which resolution levels of coefficients of
wst that you wish to set to zero.
OPTIONAL ARGUMENTS
None.
VALUE
An object of class wst where the coefficients
in resolution levels specified by levelstonull
have been
set to zero.
SIDE EFFECTS
None
DETAILS
Setting whole resolution levels of coefficients to zero can be very
useful. For example, one can construct a linear smoothing method by
setting all coefficients above a particular resolution (the
primary resolution equal to zero. Also setting particular
levels equal to zero can also be useful for removing noise which is
specific to a particular resolution level (as long as important signal
is not also contained at that level).
To remove individual coefficients on a systematic basis you probably
want to look at the threshold function.
RELEASE
Version 3.8.1 Copyright Guy Nason 1997
SEE ALSO
nullevels,
wst,
wst object,
threshold.
EXAMPLES
#
# Look at the example for nullevels.wd.
# The operation is almost identical except that wst
# objects are replaced by wd ones.