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FFT Utils provides windowing and other utility functions useful when using the FFT addon.

### Windows

```NB.*hanning v hanning function of proper length
NB.*hamming v hamming function of proper length
NB.*nuttall v blackman-harris with Nuttall parameters```

### Utility Functions

```NB.*twl v twenty log
NB.*tel v ten log```

### Example

This command plots twenty times the log magnitude of the FFT of a time series called data with each of the windows applied. The maximum is scaled to 0, and the minimum is clamped at -100.

`'keystyle open; key Unwindowed Nuttall "B-H 4" Hamming Hanning' plot (_100 >.])(- >./)"1  twl | fftw"1  (], (* nuttall), (* blackmanharris),(* hamming),: (* hanning)) data`

This example shows the effect of windowing on a simple sine wave.

`'keystyle open; key Unwindowed Nuttall "B-H 4" Hamming Hanning' plot(- >./)"1  twl | fftw"1  (], (* nuttall), (* blackmanharris),(* hamming),: (* hanning)) sin i. 128`