In this article, we are going to discuss ways in which we can create a list of dictionaries in Python.
Input: d = [{7058: 'sravan', 7059: 'jyothika', 7072: 'harsha', 7075: 'deepika'}]
print(type(d))
Output: <class 'list'>
Explanation: The type of input is list data-type having dictionary init.
List of Dictionary in Python
Below are the topics that we will cover in this article:
- Create a List of Dictionary in Python
- Accessing Dictionary Elements from a Python List of Dictionary
- Create a List of Multiple Dictionary in Python
- Accessing Dictionary Elements from a Python List of Multiple Dictionaries
- Append a Dictionary to Python List of Dictionary
- Update a Dictionary to Python List of Dictionary
A list of dictionaries means the dictionary is present as an element in the Python List.
Example:
[ {1: "Geeks", 2: "Lazyroar"} ]
Create a List of Dictionary in Python
A Python list of dictionaries can be created with the following syntax:
Syntax:
[ {‘key’:element1, ‘key’:element2, ……, ‘key’:element n} ]
Example: In this example, We will create a list and pass a dictionary to it. In this case, we pass only a single dictionary, so the length of the list will be 1.
Python3
# create a list of dictionary with student # id as key and name as value data = [{ 7058 : 'sravan' , 7059 : 'jyothika' , 7072 : 'harsha' , 7075 : 'deepika' }] # display data print (data) print ( len (data)) print ( type (data)) |
Output:
[{7058: 'sravan', 7059: 'jyothika', 7072: 'harsha', 7075: 'deepika'}]
1
<class 'list'>
Accessing Dictionary Elements from a Python List of Dictionary
We can access the elements of a Python dictionary by using the index, where the index is the dictionary index and the key is the dictionary key-value
Syntax:
data[index][key]
Example: Here we will get the values of the dictionary via index value.
Python3
# create a list of dictionary with student # id as key and name as value data = [{ 7058 : 'sravan' , 7059 : 'jyothika' , 7072 : 'harsha' , 7075 : 'deepika' }] # display data of key 7058 print (data[ 0 ][ 7058 ]) # display data of key 7059 print (data[ 0 ][ 7059 ]) # display data of key 7072 print (data[ 0 ][ 7072 ]) # display data of key 7075 print (data[ 0 ][ 7075 ]) |
Output:
sravan
jyothika
harsha
deepika
Create a List of Multiple Dictionary in Python
This is similar to the above approach, except that multiple dictionaries are being passed to the list at once. A list of dictionaries can be created in Python with the following
Syntax:
[ {“key1”: “element1”, “key2”: “element2”},
{“key1: “element1”, “key2”: “element2”} ]
Example: In this program, we will create a list in Python of length 3 where the elements of the list will be dictionaries.
Python3
# create a list of dictionaries with # student id as key and name as value data = [{ 7058 : 'sravan' , 7059 : 'jyothika' , 7072 : 'harsha' , 7075 : 'deepika' }, { 7051 : 'fathima' , 7089 : 'mounika' , 7012 : 'thanmai' , 7115 : 'vasavi' }, { 9001 : 'ojaswi' , 1289 : 'daksha' , 7045 : 'parvathi' , 9815 : 'bhavani' }] print (data) |
Output:
[{7058: 'sravan', 7059: 'jyothika', 7072: 'harsha', 7075: 'deepika'},
{7051: 'fathima', 7089: 'mounika', 7012: 'thanmai', 7115: 'vasavi'},
{9001: 'ojaswi', 1289: 'daksha', 7045: 'parvathi', 9815: 'bhavani'}]
Accessing Dictionary Elements from a Python List of Multiple Dictionaries
Similar to the list of single Python dictionaries, we can again access all the elements using an index.
Example: In this example, we will access particular elements based on an index and key values of the dictionary in Python.
Python3
# create a list of dictionaries with # student id as key and name as value data = [{ 7058 : 'sravan' , 7059 : 'jyothika' , 7072 : 'harsha' , 7075 : 'deepika' }, { 7051 : 'fathima' , 7089 : 'mounika' , 7012 : 'thanmai' , 7115 : 'vasavi' }, { 9001 : 'ojaswi' , 1289 : 'daksha' , 7045 : 'parvathi' , 9815 : 'bhavani' }] # access third dictionary with key 9001 print (data[ 2 ][ 9001 ]) # access second dictionary with key 7012 print (data[ 1 ][ 7012 ]) # access second dictionary with key 7115 print (data[ 1 ][ 7115 ]) |
Output:
ojaswi
thanmai
vasavi
Append a Dictionary to Python List of Dictionary
We can append a new dictionary to the list of dictionaries by using the Python append() method.
Example: In this example, we have a list of a single dictionary element. We will add another dictionary to this list using the append() method.
Python3
# create a list of a dictionary # with single dictionary element data = [ { 1 : "Geeks" , 2 : "Lazyroar" } ] print (data) # create a new dictionary to be appended new_data = { 1 : "Python" , 2 : "Programming" } # appending the new dictionary to # the original list of dictionary data.append(new_data) print (data) |
Output:
[{1: 'Geeks', 2: 'Lazyroar'}]
[{1: 'Geeks', 2: 'Lazyroar'}, {1: 'Python', 2: 'Programming'}]
Update a Dictionary to Python List of Dictionary
We can also update a value of a Python dictionary in the list of dictionaries.
Example: In this example, we will update the existing list of dictionaries in various ways. First, we update a dictionary of the list by adding a new value to it. Second, we update an existing value of the dictionary and third, we delete a dictionary key-value element using the del keyword.
Python3
# create a list of a dictionaries data = [{ 1 : 'Geeks' , 2 : 'Lazyroar' }, { 1 : 'Python' , 2 : 'Programming' }] print (data) # update the dictionary value data[ 0 ][ 3 ] = "World" data[ 0 ][ 2 ] = "Hello" del data[ 1 ][ 2 ] print (data) |
Output:
[{1: 'Geeks', 2: 'Lazyroar'}, {1: 'Python', 2: 'Programming'}]
[{1: 'Geeks', 2: 'Hello', 3: 'World'}, {1: 'Python'}]