Find value in nested dictionary python
In this tutorial, you’ll learn about Python nested dictionaries – dictionaries that are the values of another dictionary. You’ll learn how to create nested dictionaries, access their elements, modify them and more. You’ll also learn how to work with nested dictionaries to convert them to a Pandas DataFrame. Show
By the end of this tutorial, you’ll have learned:
Python Nested DictionariesPython
dictionaries are container data structures that hold
In the dictionary above, we have an item called
An interesting thing about Python dictionaries is that we can even use other dictionaries as their values. This brings us to the main topic of this article. Say we wanted to have a dictionary that contained the user information based on someone’s user ID. Let’s create a dictionary that stores the information on multiple users, broken out by an ID:
In this example, our earlier dictionary was embedded into the new, larger dictionary. What we’ve done is created a new, nested dictionary. In the following section, we work through how to create nested dictionaries. Creating Nested Dictionaries in PythonIn this section, you’ll learn how to create nested dictionaries. Nested dictionaries are dictionaries that have another dictionary as one or more of their values. Let’s walk through how we can create Python nested dictionaries. Let’s take a look at an example:
Let’s break down what we did here:
Accessing Items in Nested Dictionaries in PythonIn this section, you’ll learn how to access items in a nested Python dictionary. In an earlier section, we explored using the
We can see that this returned a dictionary! Since a dictionary was returned we can access an item in the returned dictionary. Say we wanted to access the
We can call the Modifying Items in Nested Dictionaries in PythonIn this section, you’ll learn how to modify items in nested dictionaries. In order to modify items, we use the same process as we would for setting a new item in a dictionary. In this case, we simply need to navigate a little further down, to a key of a nested dictionary. Say we wanted to change the profession for user 2 to
In this case, we were able to access the key’s value through direct assignment. If that key didn’t previously exist, then the key (and the value) would have been created. Deleting Items in Nested Dictionaries in PythonPython dictionaries use the
Similarly, we can delete an entire
nested dictionary using the same method. Because the nested dictionary is actually just a
In the next section, you’ll learn how to iterate through nested dictionaries in Python. Iterating Through Nested Dictionaries in PythonIn this section, you’ll learn how to iterate through nested dictionaries. This can be helpful when you want to print out the values in the dictionary. We can build a recursive function to handle this. Let’s see what this looks like:
Converting a Nested Python Dictionary to a Pandas DataFrameIn this final section,
you’ll learn how to convert a nested dictionary to a Pandas DataFrame. We can simply pass in the nested dictionary into the To work around this, we can transpose the DataFrame using the
ConclusionIn this tutorial, you learned about nested dictionaries in Python. You learned what nested dictionaries are. Then you learned how to access, modify, and delete their items. Finally, you learned how to iterate over nested dictionaries as well as how to read them into Pandas DataFrames. Additional ResourcesTo learn more about related topics, check out the tutorials below:
How do you get a value from a nested dictionary Python?Access Values using get()
Another way to access value(s) in a nested dictionary ( employees ) is to use the dict. get() method. This method returns the value for a specified key. If the specified key does not exist, the get() method returns None (preventing a KeyError ).
How do you iterate through a nested dictionary in Python?Iterate over all values of a nested dictionary in python
For a normal dictionary, we can just call the items() function of dictionary to get an iterable sequence of all key-value pairs.
How do you find the values of a key in a list of dictionaries in Python?Use a list comprehension to find the values of a key in a list of dictionaries. Use the list comprehension syntax [dict[key] for dict in list_of_dicts] to get a list containing the corresponding value for each occurrence of key in the list of dictionaries list_of_dicts .
How do you find the value of the dictionary?You can use the get() method of the dictionary ( dict ) to get any default value without an error if the key does not exist. Specify the key as the first argument. The corresponding value is returned if the key exists, and None is returned if the key does not exist.
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