Python Numpy JSON Encoder

numpy_json_encoder.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# @author loretoparisi at gmail dot com
# Copyright (c) 2020 Loreto Parisi
#


import numpy as np
import json

class NumpyEncoder(json.JSONEncoder):
    """ Custom encoder for numpy data types """
    def default(self, obj):
        if isinstance(obj, (np.int_, np.intc, np.intp, np.int8,
                            np.int16, np.int32, np.int64, np.uint8,
                            np.uint16, np.uint32, np.uint64)):

            return int(obj)

        elif isinstance(obj, (np.float_, np.float16, np.float32, np.float64)):
            return float(obj)

        elif isinstance(obj, (np.complex_, np.complex64, np.complex128)):
            return {'real': obj.real, 'imag': obj.imag}

        elif isinstance(obj, (np.ndarray,)):
            return obj.tolist()

        elif isinstance(obj, (np.bool_)):
            return bool(obj)

        elif isinstance(obj, (np.void)): 
            return None

        return json.JSONEncoder.default(self, obj)

Useful when encoding numpy objects as JSON like in Dataset Statistics with Python Pandas