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Book4_Ch02_Python_Codes/Bk4_Ch2_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_Ch2_11.py
+
+import numpy as np
+a = np.array([-2, 1, 1])
+b = np.array([1, -2, -1])
+# a = [-2, 1, 1]
+# b = [1, -2, -1]
+
+# calculate cross product of row vectors
+a_cross_b = np.cross(a, b)
+
+a_col = np.array([[-2], [1], [1]])
+b_col = np.array([[1], [-2], [-1]])
+
+# calculate cross product of column vectors
+a_cross_b_col = np.cross(a_col,b_col,axis=0)