Adding Two Vectors with Different Sizes in Python

[Eli]

Sometimes a need arises to add two Numpy arrays, which are simply vectors in mathematical terms, of different sizes. Suppose you have two Numpy arrays, x and y with differing lengths, then the logical and convenient way to add them is by the simple python code below.

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1. import numpy as np
2.  
3. x = np.array([0, 1, 5, 10, 20, 30, 40, 50])
4. y = np.array([1, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100])
5.  
6. if len(x) < len(y):
7.     z = y.copy()
8.     z[:len(x)] += x
9. else:
10.     z = x.copy()
11.     z[:len(y)] += y
12.  
13. print(z)