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I'm writing code to receive an arbitrary object (possibly nested) capable of being converted to JSON.
The default behavior for Python's builtin JSON encoder is to convert NaNs to NaN, e.g. json.dumps(np.NaN) results in NaN. How can I change this NaN value to null?
I tried to subclass JSONEncoder and override the default() method as follows:
from json import JSONEncoder, dumps import numpy as np class NanConverter(JSONEncoder): def default(self, obj): try: _ = iter(obj) except TypeError: if isinstance(obj, float) and np.isnan(obj): return "null" return JSONEncoder.default(self, obj) >>> d = {'a': 1, 'b': 2, 'c': 3, 'e': np.nan, 'f': [1, np.nan, 3]} >>> dumps(d, cls=NanConverter) '{"a": 1, "c": 3, "b": 2, "e": NaN, "f": [1, NaN, 3]}' EXPECTED RESULT: '{"a": 1, "c": 3, "b": 2, "e": null, "f": [1, null, 3]}'
829
NaN isn't valid JSON (https://tools.ietf.org/html/rfc8259 sec 6) and should probably be changed to null.
The json. dumps() method allows us to convert a python object into an equivalent JSON object. Or in other words to send the data from python to json. The json. dump() method allows us to convert a python object into an equivalent JSON object and store the result into a JSON file at the working directory.
A fp is a file pointer used to write JSON formatted data into file. Python json module always produces string objects, not bytes objects, therefore, fp.
json loads -> returns an object from a string representing a json object. json dumps -> returns a string representing a json object from an object. load and dump -> read/write from/to file instead of string.
This seems to achieve my objective:
import simplejson >>> simplejson.dumps(d, ignore_nan=True) Out[3]: '{"a": 1, "c": 3, "b": 2, "e": null, "f": [1, null, 3]}' If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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