pywt

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#!/usr/bin/env python
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# Note: This demo is a repeat of wp_2d, but using WaveletPacketND instead
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import matplotlib.pyplot as plt
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import numpy as np
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import pywt.data
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from pywt import WaveletPacketND
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arr = pywt.data.aero()
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maxlevel = 2
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wp2 = WaveletPacketND(arr, 'db2', 'symmetric', maxlevel=maxlevel)
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# Show original figure
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plt.imshow(arr, interpolation="nearest", cmap=plt.cm.gray)
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fig = plt.figure()
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i = 1
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nsubplots = len(wp2.get_level(maxlevel, 'natural'))
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nrows = int(np.floor(np.sqrt(nsubplots)))
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ncols = int(np.ceil(nsubplots/nrows))
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for node in wp2.get_level(maxlevel, 'natural'):
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    ax = fig.add_subplot(nrows, ncols, i)
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    ax.set_title(f"{node.path_tuple}")
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    ax.imshow(np.sqrt(np.abs(node.data)), origin='upper',
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              interpolation="nearest", cmap=plt.cm.gray)
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    ax.set_axis_off()
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    i += 1
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plt.show()
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