Store Dictionary with Numpy Arrays as Json

Dictionaries with Numpy Arrays in it cannot be stored as a JSON object by default. Therefore, to so store it as JSON, we need to convert all the Numpy arrays inside the dictionary to lists. This can be done by using the following code:

import json
import numpy as np

class NumpyEncoder(json.JSONEncoder):
    def default(self, obj):
        if isinstance(obj, np.ndarray):
            return obj.tolist()
        return json.JSONEncoder.default(self, obj)



array = np.array([[1, 2, 3], [4, 5, 6]])
dictionary = {
    'array': array,
    'array inside a list': [array],
    'array inside a tuple inside a list': [1, (2, 3, 4, array)]
}
json_string = json.dumps(dictionary, cls=NumpyEncoder)
print(json_string)

"""
Output:
{
  "array": [[1, 2, 3], [4, 5, 6]],
  "array inside a list": [[[1, 2, 3], [4, 5, 6]]],
  "array inside a tuple inside a list": [1, [2, 3, 4, [[1, 2, 3], [4, 5, 6]]]]
}
"""

Source: https://stackoverflow.com/a/47626762/10307491