xfft

calculate the spectra and cross-spectra

xfft(x, spans = NULL, kernel = NULL, taper = 0.1, pad = 0,
  fast = TRUE, demean = FALSE, detrend = TRUE, plot = TRUE,
  na.action = na.fail, ...)

Arguments

x	univariate or multivariate time series.
spans	vector of odd integers giving the widths of modified Daniell smoothers to be used to smooth the periodogram.
kernel	alternatively, a kernel smoother of class `"tskernel"`.
taper	specifies the proportion of data to taper. A split cosine bell taper is applied to this proportion of the data at the beginning and end of the series.
pad	proportion of data to pad. Zeros are added to the end of the series to increase its length by the proportion `pad`.
fast	logical; if `TRUE`, pad the series to a highly composite length.
demean	logical. If `TRUE`, subtract the mean of the series.
detrend	logical. If `TRUE`, remove a linear trend from the series. This will also remove the mean.
plot	plot the periodogram?
na.action	`NA` action function.
...	graphical arguments passed to `plot.spec`.

matrix of spectra