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Converting JSON String to Dictionary Not List

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python

json

People also ask

How do I convert a JSON to a dictionary?

To convert json to dict in Python, use the json. load() function. The json. load() is a built-in function that deserializes json data to a Python object.

Why is my JSON loading as a list?

It can happen because your JSON is an array with a single object inside, for example, somebody serialized the Python list into JSON. So when you parse it, you get a list object in return. In this case, you need to iterate the list to access data.

How do I load a JSON string into a dictionary in Python?

To convert a Python string to a dictionary, use the json. loads() function. The json. loads() is a built-in Python function that converts a valid string to a dict.

Is JSON a dictionary or a list?

A “JSON object” is very similar to a Python dictionary. A “JSON array” is very similar to a Python list. In the same way that JSON objects can be nested within arrays or arrays nested within objects, Python dictionaries can be nested within lists or lists nested within dictionaries.


Your JSON is an array with a single object inside, so when you read it in you get a list with a dictionary inside. You can access your dictionary by accessing item 0 in the list, as shown below:

json1_data = json.loads(json1_str)[0]

Now you can access the data stored in datapoints just as you were expecting:

datapoints = json1_data['datapoints']

I have one more question if anyone can bite: I am trying to take the average of the first elements in these datapoints(i.e. datapoints[0][0]). Just to list them, I tried doing datapoints[0:5][0] but all I get is the first datapoint with both elements as opposed to wanting to get the first 5 datapoints containing only the first element. Is there a way to do this?

datapoints[0:5][0] doesn't do what you're expecting. datapoints[0:5] returns a new list slice containing just the first 5 elements, and then adding [0] on the end of it will take just the first element from that resulting list slice. What you need to use to get the result you want is a list comprehension:

[p[0] for p in datapoints[0:5]]

Here's a simple way to calculate the mean:

sum(p[0] for p in datapoints[0:5])/5. # Result is 35.8

If you're willing to install NumPy, then it's even easier:

import numpy
json1_file = open('json1')
json1_str = json1_file.read()
json1_data = json.loads(json1_str)[0]
datapoints = numpy.array(json1_data['datapoints'])
avg = datapoints[0:5,0].mean()
# avg is now 35.8

Using the , operator with the slicing syntax for NumPy's arrays has the behavior you were originally expecting with the list slices.


Here is a simple snippet that read's in a json text file from a dictionary. Note that your json file must follow the json standard, so it has to have " double quotes rather then ' single quotes.

Your JSON dump.txt File:

{"test":"1", "test2":123}

Python Script:

import json
with open('/your/path/to/a/dict/dump.txt') as handle:
    dictdump = json.loads(handle.read())

You can use the following:

import json

 with open('<yourFile>.json', 'r') as JSON:
       json_dict = json.load(JSON)

 # Now you can use it like dictionary
 # For example:

 print(json_dict["username"])

The best way to Load JSON Data into Dictionary is You can user the inbuilt json loader.

Below is the sample snippet that can be used.

import json
f = open("data.json")
data = json.load(f))
f.close()
type(data)
print(data[<keyFromTheJsonFile>])