How to compare two array of numpy to get which one is greater than another one

When you compare a array to another array with numpy module. You would meet a error like this:

ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

In order to solve this problem. Use np.all() as follows :

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>>> import numpy as np
>>> a = np.array([1,2,3,4,5])
>>> b = np.array([6,7,8,9,10])
>>> c = np.array([1,2,3,9,5])
>>> if np.all(a > b):
...     print("test")
... else:
...     print("what")
... 
what
>>> if np.any(c > a):
...     print("any")
... 
any

Reference