Last Updated : 28 Feb, 2023
In this article, we will discuss how to iterate over a nested dictionary in Python.
Nested dictionary means dictionary inside a dictionary and we are going to see every possible way of iterating over such a data structure.
Nested dictionary in use:
{'Student 1': {'Name': 'Bobby', 'Id': 1, 'Age': 20},
'Student 2': {'Name': 'ojaswi', 'Id': 2, 'Age': 22},
'Student 3': {'Name': 'rohith', 'Id': 3, 'Age': 20}}
For this we will use for loop to iterate through a dictionary to get the all the key , values of nested dictionaries.
Syntax:
for i in dictionary_name: print(dictionary_name[i])
where
Example: Python program to get the nested dictionaries from a dictionary
Python3
# create a nested dictionary with 3
# fields of 3 students
data = {
'Student 1': {'Name': 'Bobby', 'Id': 1, "Age": 20},
'Student 2': {'Name': 'ojaswi', 'Id': 2, "Age": 22},
'Student 3': {'Name': 'rohith', 'Id': 3, "Age": 20},
}
# iterate all the nested dictionaries with
# both keys and values
for i in data:
# display
print(data[i])
Output:
{'Name': 'Bobby', 'Id': 1, 'Age': 20} {'Name': 'ojaswi', 'Id': 2, 'Age': 22} {'Name': 'rohith', 'Id': 3, 'Age': 20}
Time complexity : O(n)
Space complexity : O(n)
It is also possible to get only either keys or values if the that is what the requirement asks for. Again for this for loop is employed with a little variation.
To get keys from the nested dictionary for each iteration keys() function is called.
Syntax:
data[i].keys()
Example: Python program to get keys from the nested dictionary
Python3
# create a nested dictionary with 3 fields of 3 students
data = {
'Student 1': {'Name': 'Bobby', 'Id': 1, "Age": 20},
'Student 2': {'Name': 'ojaswi', 'Id': 2, "Age": 22},
'Student 3': {'Name': 'rohith', 'Id': 3, "Age": 20},
}
# iterate all the nested dictionaries with keys
for i in data:
# display
print(data[i].keys())
Output:
dict_values(['Name', Id, Age]) dict_values(['Name', Id, Age]) dict_values(['Name', Id, Age])
Time complexity : O(n)
Space complexity : O(n)
Similarly to get values, after each iteration values() function is used to get the job done.
Syntax:
data[i].values()
Example: Python program to get values from the nested dictionary
Python3
# create a nested dictionary with 3 fields of 3 students
data = {
'Student 1': {'Name': 'Bobby', 'Id': 1, "Age": 20},
'Student 2': {'Name': 'ojaswi', 'Id': 2, "Age": 22},
'Student 3': {'Name': 'rohith', 'Id': 3, "Age": 20},
}
# iterate all the nested dictionaries with values
for i in data:
# display
print(data[i].values())
Output:
dict_values(['Bobby', 1, 20]) dict_values(['ojaswi', 2, 22]) dict_values(['rohith', 3, 20])
Time complexity : O(n)
Space complexity : O(n)
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4