Python json get first element

Question

Like other answers have pointed out, the accepted answer to this question seems to ignore the data structure misunderstanding of the original poster.

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How do I get the first element of a JSON?
How do you access data from a JSON object in Python?
How do I extract text from a JSON file in Python?
How do I access JSON elements?

The main issue seems to be that the original solution treats the JSON purely as a dictionary, when in fact it is a...

dictionary within a list, within a dictionary, within a dictionary

Thus, ['data'] is required to access the top-level key:value pair of the dictionary, ['current_conditions'] accesses the next level of dictionary, then [0] must be used to access the first element of the list (which has only 1 element).

Only then can ['temp_C'] be used to access the actual value for that key and retrieve the data.

x={
  "data": {
            "current_condition": 
                [{
                    "cloudcover": "0",
                    "humidity": "54",
                    "observation_time": "08:49 AM",
                    "precipMM": "0.0",
                    "pressure": "1025",
                    "temp_C": "10",
                    "temp_F": "50",
                    "visibility": "10",
                    "weatherCode": "113",
                    "weatherDesc": 
                        [{
                            "value": "Sunny"
                        }],
                    
                    "weatherIconUrl": 
                        [{
                            "value": "http:\/\/www.worldweatheronline.com\/images\/wsymbols01_png_64\/wsymbol_0001_sunny.png"
                        }],
                    "winddir16Point": "E",
                    "winddirDegree": "100",
                    "windspeedKmph": "22",
                    "windspeedMiles": "14"
                },
                {
                    "cloudcover": "0",
                    "humidity": "54",
                    "observation_time": "08:49 AM",
                    "precipMM": "0.0",
                    "pressure": "1025",
                    "temp_C": "5",
                    "temp_F": "50",
                    "visibility": "10",
                    "weatherCode": "113",
                    "weatherDesc": 
                        [{
                            "value": "Sunny"
                        }],
                    
                    "weatherIconUrl": 
                        [{
                            "value": "http:\/\/www.worldweatheronline.com\/images\/wsymbols01_png_64\/wsymbol_0001_sunny.png"
                        }],
                    "winddir16Point": "E",
                    "winddirDegree": "100",
                    "windspeedKmph": "22",
                    "windspeedMiles": "14"
                }    ]        
            }
}


print(x['data']['current_condition'][0]['weatherDesc'][0]['value'])

# results in 'Sunny'

In answer to another question in comments,

"Is there a way to do this without knowing the index, assuming there were more current condition entries?"

Assuming numerous current_condition entries it is unlikely that you would just want one value, or if you do then you'll likely have another piece of information to locate that specific value (i.e. location or something).

Assuming you data set is named x, i.e. x = {"data": ...}.

If you want all of the current_condition entries you can loop through the list (of current_conditions) using:

y = []

for index in range(0,len(x['data']['current_condition']))
   y.append(x['data']['current_condition'][index]['temp_C'])

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Posted by ada ada

How to access first element of JSON object array?

{"symbols_requested":3,"symbols_returned":3,"data":[{"symbol":"AAPL","name":"Apple}]

I want to access name

Steven Parker

1 Answer

Hi, I got alerted by your tag; but there's a lot of students (and occasionally instructors!) willing to help — next time try giving the whole community at least a day to answer and you can always tag someone(s) later.

This code appears to be a JavaScript object literal. It's JSON-compatible, but it's not in JSON format now. It also seems to have two errors:

a quote mark is missing after "Apple"
and closing is brace is missing at the very end

So if we fix those and format it to make it easier to read:

{"symbols_requested": 3,
  "symbols_returned": 3,
  "data": [ {"symbol": "AAPL",
             "name": "Apple"} ]
}

We can see that "name" is a property of an object that is inside the first element of an array named "data", which is itself inside the main object. So for example, if this object were being reference by a variable named "test", you could access the name as:

test.data[0].name

How do I get the first element of a JSON?

Use object. keys(objectName) method to get access to all the keys of object. Now, we can use indexing like Object. keys(objectName)[0] to get the key of first element of object.

How do you access data from a JSON object in Python?

Python has a built-in package called json, which can be used to work with JSON data. It's done by using the JSON module, which provides us with a lot of methods which among loads() and load() methods are gonna help us to read the JSON file. ... Deserialization of JSON..

How do I extract text from a JSON file in Python?

So first thing you need to import the 'json' module into the file. Then create a simple json object string in python and assign it to a variable. Now we will use the loads() function from 'json' module to load the json data from the variable. We store the json data as a string in python with quotes notation.