# hamming

Hamming window

## Syntax

``w = hamming(L)``
``w = hamming(L,sflag)``

## Description

example

````w = hamming(L)` returns an `L`-point symmetric Hamming window.```

example

````w = hamming(L,sflag)` returns a Hamming window using the window sampling specified by `sflag`.```

## Examples

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Create a 64-point Hamming window. Display the result using `wvtool`.

```L = 64; wvtool(hamming(L))```

Design two Hamming windows:

• The first window has N = 64 and is symmetric.

• The second window has N = 63 and is periodic.

Display the two windows.

```Hs = hamming(64,'symmetric'); Hp = hamming(63,'periodic'); wvt = wvtool(Hs,Hp); legend(wvt.CurrentAxes,'Symmetric','Periodic')```

## Input Arguments

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Window length, specified as a positive integer.

Data Types: `single` | `double`

Window sampling method, specified as:

• `'symmetric'` — Use this option when using windows for filter design.

• `'periodic'` — This option is useful for spectral analysis because it enables a windowed signal to have the perfect periodic extension implicit in the discrete Fourier transform. When `'periodic'` is specified, the function computes a window of length `L` + 1 and returns the first `L` points.

## Output Arguments

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Hamming window, returned as a column vector.

## Algorithms

The following equation generates the coefficients of a Hamming window:

`$w\left(n\right)=\begin{array}{cc}0.54-0.46\mathrm{cos}\left(2\pi \frac{n}{N}\right),& 0\le n\le N\end{array}.$`

The window length L = N + 1.

## References

[1] Oppenheim, Alan V., Ronald W. Schafer, and John R. Buck. Discrete-Time Signal Processing. Upper Saddle River, NJ: Prentice Hall, 1999.