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Book4_Ch06_Python_Codes/Bk4_Ch6_03.py

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+
+###############
+# Authored by Weisheng Jiang
+# Book 4  |  From Basic Arithmetic to Machine Learning
+# Published and copyrighted by Tsinghua University Press
+# Beijing, China, 2022
+###############
+
+
+# Bk4_Ch6_03.py
+
+import numpy as np
+from matplotlib import pyplot as plt
+import seaborn as sns
+
+A = np.array([[-1,  1],
+              [0.7, -0.4]])
+
+B = np.array([[0.5, -0.6],
+             [-0.8, 0.3]])
+
+A_kron_B = np.kron(A, B)
+
+fig, axs = plt.subplots(1, 5, figsize=(12, 5))
+
+plt.sca(axs[0])
+ax = sns.heatmap(A,cmap='RdYlBu_r',vmax = 1,vmin = -1,
+                 cbar_kws={"orientation": "horizontal"})
+ax.set_aspect("equal")
+plt.title('A')
+
+plt.sca(axs[1])
+plt.title('$\otimes$')
+plt.axis('off')
+
+plt.sca(axs[2])
+ax = sns.heatmap(B,cmap='RdYlBu_r',vmax = 1,vmin = -1,
+                 cbar_kws={"orientation": "horizontal"})
+ax.set_aspect("equal")
+plt.title('B')
+
+plt.sca(axs[3])
+plt.title('=')
+plt.axis('off')
+
+plt.sca(axs[4])
+ax = sns.heatmap(A_kron_B,cmap='RdYlBu_r',vmax = 1,vmin = -1,
+                 cbar_kws={"orientation": "horizontal"})
+ax.set_aspect("equal")
+plt.title('C')