Converting JSON String to Dictionary Not List Converting JSON String to Dictionary Not List python-3.x python-3.x

Converting JSON String to Dictionary Not List


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 numpyjson1_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 jsonwith 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"])