R: Hanning Filter

hanning {dplR} | R Documentation

## Hanning Filter

### Description

Applies a Hanning filter of length `n` to `x`.

### Usage

    hanning(x, n = 7)

### Arguments

`x` | a vector
`n` | length of the Hanning filter, defaults to 7

### Details

This applies a low frequency Hanning (a.k.a. Hann) filter to `x` with weight set to `n`.

### Value

A filtered vector.

### Author(s)

Andy Bunn. Patched and improved by Mikko Korpela.

### References

Oppenheim, A. V., Schafer, R. W., and Buck, J. R. (1999) Discrete-Time Signal Processing. Prentice-Hall, 2nd edition. ISBN-13: 978-0-13-754920-7.

### See Also

`filter`

### Examples

    library(graphics)
    library(utils)
    data(ca533)
    yrs <- time(ca533)
    y <- ca533[, 1]
    not.na <- !is.na(y)
    yrs <- yrs[not.na]
    y <- y[not.na]
    plot(yrs, y, xlab = "Years", ylab = "Series1 (mm)",
         type = "l", col = "grey")
    lines(yrs, hanning(y, n = 9), col = "red", lwd = 2)
    lines(yrs, hanning(y, n = 21), col = "blue", lwd = 2)
    legend("topright", c("Series", "n=9", "n=21"),
           fill=c("grey", "red", "blue"))

[Package dplR version 1.7.1 Index]