Converting JSON String to Dictionary Not List
Question:
I am trying to pass in a JSON file and convert the data into a dictionary.
So far, this is what I have done:
import json
json1_file = open('json1')
json1_str = json1_file.read()
json1_data = json.loads(json1_str)
I’m expecting json1_data to be a dict type but it actually comes out as a list type when I check it with type(json1_data).
What am I missing? I need this to be a dictionary so I can access one of the keys.
Answers:
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())
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>])
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"])
pass the data using javascript ajax from get methods
**//javascript function
function addnewcustomer(){
//This function run when button click
//get the value from input box using getElementById
var new_cust_name = document.getElementById("new_customer").value;
var new_cust_cont = document.getElementById("new_contact_number").value;
var new_cust_email = document.getElementById("new_email").value;
var new_cust_gender = document.getElementById("new_gender").value;
var new_cust_cityname = document.getElementById("new_cityname").value;
var new_cust_pincode = document.getElementById("new_pincode").value;
var new_cust_state = document.getElementById("new_state").value;
var new_cust_contry = document.getElementById("new_contry").value;
//create json or if we know python that is call dictionary.
var data = {"cust_name":new_cust_name, "cust_cont":new_cust_cont, "cust_email":new_cust_email, "cust_gender":new_cust_gender, "cust_cityname":new_cust_cityname, "cust_pincode":new_cust_pincode, "cust_state":new_cust_state, "cust_contry":new_cust_contry};
//apply stringfy method on json
data = JSON.stringify(data);
//insert data into database using javascript ajax
var send_data = new XMLHttpRequest();
send_data.open("GET", "http://localhost:8000/invoice_system/addnewcustomer/?customerinfo="+data,true);
send_data.send();
send_data.onreadystatechange = function(){
if(send_data.readyState==4 && send_data.status==200){
alert(send_data.responseText);
}
}
}
django views
def addNewCustomer(request):
#if method is get then condition is true and controller check the further line
if request.method == "GET":
#this line catch the json from the javascript ajax.
cust_info = request.GET.get("customerinfo")
#fill the value in variable which is coming from ajax.
#it is a json so first we will get the value from using json.loads method.
#cust_name is a key which is pass by javascript json.
#as we know json is a key value pair. the cust_name is a key which pass by javascript json
cust_name = json.loads(cust_info)['cust_name']
cust_cont = json.loads(cust_info)['cust_cont']
cust_email = json.loads(cust_info)['cust_email']
cust_gender = json.loads(cust_info)['cust_gender']
cust_cityname = json.loads(cust_info)['cust_cityname']
cust_pincode = json.loads(cust_info)['cust_pincode']
cust_state = json.loads(cust_info)['cust_state']
cust_contry = json.loads(cust_info)['cust_contry']
#it print the value of cust_name variable on server
print(cust_name)
print(cust_cont)
print(cust_email)
print(cust_gender)
print(cust_cityname)
print(cust_pincode)
print(cust_state)
print(cust_contry)
return HttpResponse("Yes I am reach here.")**
I am working with a Python code for a REST API, so this is for those who are working on similar projects.
I extract data from an URL using a POST request and the raw output is JSON. For some reason the output is already a dictionary, not a list, and I’m able to refer to the nested dictionary keys right away, like this:
datapoint_1 = json1_data['datapoints']['datapoint_1']
where datapoint_1 is inside the datapoints dictionary.
I am trying to pass in a JSON file and convert the data into a dictionary.
So far, this is what I have done:
import json
json1_file = open('json1')
json1_str = json1_file.read()
json1_data = json.loads(json1_str)
I’m expecting json1_data to be a dict type but it actually comes out as a list type when I check it with type(json1_data).
What am I missing? I need this to be a dictionary so I can access one of the keys.
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())
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>])
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"])
pass the data using javascript ajax from get methods
**//javascript function
function addnewcustomer(){
//This function run when button click
//get the value from input box using getElementById
var new_cust_name = document.getElementById("new_customer").value;
var new_cust_cont = document.getElementById("new_contact_number").value;
var new_cust_email = document.getElementById("new_email").value;
var new_cust_gender = document.getElementById("new_gender").value;
var new_cust_cityname = document.getElementById("new_cityname").value;
var new_cust_pincode = document.getElementById("new_pincode").value;
var new_cust_state = document.getElementById("new_state").value;
var new_cust_contry = document.getElementById("new_contry").value;
//create json or if we know python that is call dictionary.
var data = {"cust_name":new_cust_name, "cust_cont":new_cust_cont, "cust_email":new_cust_email, "cust_gender":new_cust_gender, "cust_cityname":new_cust_cityname, "cust_pincode":new_cust_pincode, "cust_state":new_cust_state, "cust_contry":new_cust_contry};
//apply stringfy method on json
data = JSON.stringify(data);
//insert data into database using javascript ajax
var send_data = new XMLHttpRequest();
send_data.open("GET", "http://localhost:8000/invoice_system/addnewcustomer/?customerinfo="+data,true);
send_data.send();
send_data.onreadystatechange = function(){
if(send_data.readyState==4 && send_data.status==200){
alert(send_data.responseText);
}
}
}
django views
def addNewCustomer(request):
#if method is get then condition is true and controller check the further line
if request.method == "GET":
#this line catch the json from the javascript ajax.
cust_info = request.GET.get("customerinfo")
#fill the value in variable which is coming from ajax.
#it is a json so first we will get the value from using json.loads method.
#cust_name is a key which is pass by javascript json.
#as we know json is a key value pair. the cust_name is a key which pass by javascript json
cust_name = json.loads(cust_info)['cust_name']
cust_cont = json.loads(cust_info)['cust_cont']
cust_email = json.loads(cust_info)['cust_email']
cust_gender = json.loads(cust_info)['cust_gender']
cust_cityname = json.loads(cust_info)['cust_cityname']
cust_pincode = json.loads(cust_info)['cust_pincode']
cust_state = json.loads(cust_info)['cust_state']
cust_contry = json.loads(cust_info)['cust_contry']
#it print the value of cust_name variable on server
print(cust_name)
print(cust_cont)
print(cust_email)
print(cust_gender)
print(cust_cityname)
print(cust_pincode)
print(cust_state)
print(cust_contry)
return HttpResponse("Yes I am reach here.")**
I am working with a Python code for a REST API, so this is for those who are working on similar projects.
I extract data from an URL using a POST request and the raw output is JSON. For some reason the output is already a dictionary, not a list, and I’m able to refer to the nested dictionary keys right away, like this:
datapoint_1 = json1_data['datapoints']['datapoint_1']
where datapoint_1 is inside the datapoints dictionary.