Mastering Python Second Edition Release Code

CH_15_scientific_python/T_06_stumpy.rst

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+>>> import numpy as np
+>>> import stumpy
+
+>>> temperatures = np.array([22., 21., 22., 21., 22., 23.])
+
+>>> window_size = 3
+
+# Calculate a Euclidean distance matrix between the windows
+
+>>> stump = stumpy.stump(temperatures, window_size)
+
+# Show the distance matrix. The row number is the index in the
+input array. The first column is the distance, the next columns
+are the indices of the nearest match, the left match and the
+right match.
+
+>>> stump
+array([[0.0, 2, -1, 2],
+      [2.449489742783178, 3, -1, 3],
+      [0.0, 0, 0, -1],
+      [2.449489742783178, 1, 1, -1]], dtype=object)
+
+# As we can see in the matrix above, the first window has a
+distance of 0 to the window at index 2 meaning that they are
+identical. We can easily verify that by showing both windows:
+
+# The first window:
+
+>>> temperatures[0:window_size]
+array([22., 21., 22.])
+
+# The window at index 2:
+
+>>> temperatures[2:2 + window_size]
+array([22., 21., 22.])