pergram(y)# S3 method for pergram
plot(x, add = FALSE, lty = 1, xlab = "Frequency",
ylab = "Periodogram", main = "Periodogram", ylim = c(0, max(po[,
2])), ...)
# S3 method for pergram
plot_cum(x, xlab = "Frequency", ylab = "Periodogram",
main = "Cumulative periodogram", ylim = c(0, max(cpo + 1.358/(a +
0.12 + 0.11/a))), ...)