cpt(x, crystal.names=NULL, basis=NULL, cost.fun="entropy",
n.levels=6, taper="poly2", dct.type=2, boundary="periodic",
n.taper=NULL, scale=NULL, thresh=NULL, p=2, prob=.5)
icpt(x)
icpt only, an object of class
cpt.
"cj.b"
where
j is an integer giving the level and
b is an integer from
0 to
2^j-1
giving the block number within level
j.
If
crystal.names is supplied, then
basis is ignored.
"best.basis",
"best.level",
"block.dct", or
"block.cpt".
See the corresponding function for details.
"entropy",
"threshold",
"sure", and "
lp" are available.
Only used for
"best.basis".
See
pcosts for details.
x is divided into
2^n.levels blocks each of length
length(x)/2^n.levels.
For
"best.basis",
n.levels gives the blocking factor for the finest level.
If
n.levels is bigger than
ml, where
ml is the maximum possible level,
computed from the
max.level function, then
n.levels is set to
ml and
a warning message is given.
2 or
4 indicating which of DCT-II or DCT-IV should be used.
See the function
dct for details.
"boxcar", "poly1", "poly2", "poly3", "poly4", "poly5", or
"trig".
See the function
cp.table for details.
"cp.reflect", "periodic"
and
"zero".
See the function
cp.table for details.
2*n.taper.
By default,
n.taper is set to
length(x)/2^(n.level+1),
which is the maximum possible length at the finest blocking level.
cost.fun.
See the function
pcosts for details.
(0,2] giving the degree of the
lpnorm when
cost.fun is
"lp".
See the function
pcosts for details.
cost.fun is
"threshold" or
"sure".
See the function
pcosts for details.
(0,1) used to
compute the threshold for when
cost.fun is
"threshold".
See the function
pcosts for details.
cpt, inheriting from the class
crystal.vector.
icpt(x) performs the inverse transform from the
cpt object
x,
as the generic function
reconstruct does for
cpt objects.
The algorithms for the taper functions are given in the
S+WAVELETS User's Manual,
in the section "Cosine Packet Algorithms". They are discussed in
greater depth in Wickerhauser (1994).
The default optional arguments
n.levels, taper, dct.type, boundary
can be reset using function
wavelet.options, see
wavelet.options for details.
Wickerhauser, M. V. (1994). Adapted Wavelet Analysis from Theory to Software. A. K. Peters Ltd, Wellesley, MA.
x <- make.signal("linchirp")
bbx <- cpt(x, basis="best.basis")
eda.plot(bbx)