list like that returned by the time series spectrum estimation
functions:
spectrum,
spec.pgram or
spec.ar,
including at least the components
freq and
spec.
OPTIONAL ARGUMENTS:
add
if
TRUE, the spectrum plot will be superimposed on an existing spectrum plot.
This is useful to compare different spectral estimates for the same series.
type
desired type of plot. Besides the default of
"l" (lines), this could
be
"h" (high density),
"p" (points), or
"b" (both lines and points).
main
user supplied title.
xlab
label for x-axis, default is
"frequency".
ylab
label for y-axis, default is
"spectrum".
conf.band
if
TRUE, the 95% confidence interval and the bandwidth of the estimate
will be plotted in the upper right corner, and printed as subtitle.
SIDE EFFECTS:
plots the spectrum (or spectra for multivariate series)
along with a cross in the upper right corner whose vertical component
indicate the 95% confidence interval for the spectrum
(based on a chi-squared approximation)
and whose horizontal element indicates the bandwidth of the estimate.
This does not plot the coherency or phase of multivariate series.