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Book4_Ch04_Python_Codes/Bk4_Ch4_11.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_Ch4_11.py
+
+from numpy.linalg import inv
+A = np.array([[1., 2.], 
+              [3., 4.]])
+
+# matrix inverse
+A_inverse = inv(A)
+A_times_A_inv = A@A_inverse