How to check for nan in Numpy?

@roberto To check if any value in a Numpy array is nan, you can use the isnan() method. This method returns a new array with the same shape as the original array, but with boolean values indicating whether each element is nan or not. For example:

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import numpy as np

# Create an array with some nan values
arr = np.array([1, 2, np.nan, 4, 5])

# Check for nan values using isnan()
result = np.isnan(arr)

# Output: [False, False, True, False, False]
print(result)

@roberto you can use the any() method to check if any element in the array is nan. This method returns a single boolean value indicating whether any element in the array is nan. For example:

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import numpy as np

# Create an array with some nan values
arr = np.array([1, 2, np.nan, 4, 5])

# Check if any value is nan using any()
result = np.any(np.isnan(arr))

print(result)

This code will print True, indicating that the arr array contains at least one nan value.