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# Hanning in Numpy | Python

• Last Updated : 22 Jul, 2021

The Hanning window is a taper formed by using a weighted cosine.

```Syntax:  numpy.hamming(M)

Parameters:
M :  Number of points in the output window.

Returns:  AN array```

The window, with the maximum value normalized to one (the value one appears only if M is odd).

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Code #1:

 `import` `numpy as np`` ` ` ` `print``(np.hanning(``12``))`

Output:

```[ 0.          0.07937323  0.29229249  0.57115742  0.82743037  0.97974649
0.97974649  0.82743037  0.57115742  0.29229249  0.07937323  0.        ]
```

Code #2: Plotting the window and its frequency response (requires SciPy and matplotlib).

 `import` `numpy as np``import` `matplotlib.pyplot as plt``from` `numpy.fft ``import` `fft, fftshift`` ` `window ``=` `np.hanning(``51``)`` ` `plt.plot(window)``plt.title(``"Hann window"``)``plt.ylabel(``"Amplitude""``)``plt.xlabel(``"Sample"``)`` ` `plt.show()`

Output: For frequency:

 `import` `numpy as np``import` `matplotlib.pyplot as plt``from` `numpy.fft ``import` `fft, fftshift`` ` `window ``=` `np.hanning(``51``)``plt.figure()`` ` `A ``=` `fft(window, ``2048``) ``/` `25.5``mag ``=` `np.``abs``(fftshift(A))``freq ``=` `np.linspace(``-``0.5``, ``0.5``, ``len``(A))``response ``=` `20` `*` `np.log10(mag)``response ``=` `np.clip(response, ``-``100``, ``100``)`` ` `plt.plot(freq, response)``plt.title(``"Frequency response of Hanning window"``)``plt.ylabel(``"Magnitude [dB]"``)``plt.xlabel(``"Normalized frequency [cycles per sample]"``)``plt.axis(``"tight"``)``plt.show()`

Output: My Personal Notes arrow_drop_up