Plot Wavelet Functions
DESCRIPTION:
Plots wavelet and wavelet packet functions.
USAGE: 
plot(x, plot=T, J=8, periodic=F, I=1, ...)
REQUIRED ARGUMENTS:
x:
an object of class wavelet, wavelet.packet or wp.atom.
OPTIONAL ARGUMENTS:
plot:
logical flag. If TRUE, a plot is produced.
J:
an integer specifying the sampling interval 2^(-J) on which to evaluate the wavelet packet function.
periodic:
logical flag: if TRUE, then wavelet packet function is periodized.
I:
in effect only if periodic=TRUE. The wavelet packet function will be periodized with period 2^I.
...:
additional arguments can be passed to plot.
VALUE:
a list with two components, x and y:
x:
the points at which the wavelet packet function or atom is evaluated.
y:
value of the wavelet packet function or atom at each x point.
SIDE EFFECTS:
produces a plot.
DETAILS:
A wavelet or wavelet packet function is evaluated on a dyadic grid over the range of the support of the function. The sampling interval of the grid is at most 2^(-J), and may be smaller depending on the wavelet type and J.

Wavelet and wavelet packet atoms are rescaled by the coefficient and translated to the sampling interval of the original signal.

The "construction 3" in Strang (1989) on p. 617 is used to compute a wavelet function at the dyadics when it is possible. The biorthogonal wavelets "bs2.2", "bs3.1", "bs3.3" and "vs1" are infinite at all dyadics, and "construction 3" cannot be used. For these wavelets, "construction 1" in Strang (1989) on p. 616 is used to generate the plots.

For details about evaluating a wavelet function, refer to Strang (1989) or to the section "The Dilation Equation" of the S+WAVELETS User's Manual.

REFERENCES:
Strang, Gilbert (1989). Wavelets and Dilation Equations: A Brief Introduction. SIAM Review 31 (4): 614-627.
SEE ALSO:
dyadic.refine , wavelet , wavelet.packet , wp.atom .