I am quite new to python and I was trying to make two arrays or matrices, register them into a dictionary, save to a json file. Here is my code
import numpy as np
import json
array_1 = np.array([[1,2,3],[4,6,7]])
array_2 = np.array([[4,0],[9,8]])
json_data = {
'array_1': array_1,
'array_2': array_2,
}
import json
with open('json_data.json', 'wb') as fp:
json.dumps(json_data, fp)
But I get the following error:
Object of type 'ndarray' is not JSON serializable
First convert it to the python list like this:
json_data = {
'array_1': array_1.tolist(),
'array_2': array_2.tolist()
}
and then try to dump it as a json:
import json
with open('json_data.json', 'w') as fp:
json.dump(json_data, fp)
with open('json_data.json', 'w') as fp: json.dump(json_data, fp)
json.dumps() dumps to a string. Use json.dump() instead.The best and easiest way of doing this is:
import json
with open("file.json", "wb") as f:
f.write(json.dumps(dict).encode("utf-8"))
First correct your data. Correct data: json_data = { 'array_1': array_1, 'array_2': array_2 }
There is a extra ',' at the end of the line (array_2). That is the reason you are getting JSON serialization issue.
jsonmodule only knows how to serialize native Python types likelist,dict, etc. You will need to either store your arrays as Pythonlists in yourjson_datadictionary, or write a function that is called byjson.dumpsto do the conversion automatically. Read about the default parameter tojson.dumps.