pywt

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#!/usr/bin/env python
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import matplotlib.pyplot as plt
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import pywt
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import pywt.data
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arr = pywt.data.aero()
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plt.imshow(arr, interpolation="nearest", cmap=plt.cm.gray)
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level = 0
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titles = ['Approximation', ' Horizontal detail',
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          'Vertical detail', 'Diagonal detail']
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for LL, (LH, HL, HH) in pywt.swt2(arr, 'bior1.3', level=3, start_level=0):
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    fig = plt.figure()
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    for i, a in enumerate([LL, LH, HL, HH]):
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        ax = fig.add_subplot(2, 2, i + 1)
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        ax.imshow(a, origin='upper', interpolation="nearest", cmap=plt.cm.gray)
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        ax.set_title(titles[i], fontsize=12)
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    fig.suptitle(f"SWT2 coefficients, level {level}", fontsize=14)
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    level += 1
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plt.show()
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