my.acf {waveslim}R Documentation

Auotocovariance Function via the Discrete Fourier Transform

Description

Computes the autocovariance function for a time series.

Usage

my.acf(x)

Arguments

x time series

Details

The series is zero padded to twice its length before the discrete Fourier transform is applied. Only the values corresponding to nonnegative lags are provided.

Value

The autocovariance function, for all nonnegative lags, is output.

Author(s)

B. Whitcher

Examples

data(ibm)
ibm.returns <- diff(log(ibm))
plot(1:length(ibm.returns) - 1, my.acf(ibm.returns), type="h",
     xlab="lag", ylab="ACVS", main="Autocovariance Sequence for IBM Returns")

[Package Contents]