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Python : Sort a dictionary based on value and key of items

Sorting a dictionary in ascending order based on the value of the item.

The idea is to use:

sorted function. The signature of sorted funciton is sorted ( iterable, key = None, reverse = False )
- sorted function would return the sorted list generated from the items in iterable
- key specifies a function that key single argument for extracting a comparison key from each element in iterable.
- reverse when set to true would sort the list in descending order.
lambda keyword could be used to create mini anonymous functions for specifying the key in sorted function.

Thus,

iterable would be _dict.items ( ). The item returned using items ( ) function would be a tuple of key and value.
i.e key would be item [ 0 ] & value would be item [ 1 ].
key would be lambda item : item [ 1 ] as we are sorting based on the values

Python3 : Sorting a dictionary by value in ascending order

_dict = { 'Mango': 100, 'Kiwi' : 50, 'Avacado' : 60, 'Pear' : 25, 'Coconut' : 42, 'Plum' : 48 }

_dict = dict(sorted(_dict.items(), key=lambda item: item[1]))

for item in _dict.items():
    print ("Key : " + item[0] + ", Value : " + str(item[1]))

Output

Key : Pear, Value : 25
Key : Coconut, Value : 42
Key : Plum, Value : 48
Key : Kiwi, Value : 50
Key : Avacado, Value : 60
Key : Mango, Value : 100

To sort the dictionary by value in descending order, we would set the reverse=True in the sorted function.

Python3 : Sorting a dictionary by value in descending order

_dict = { 'Alfa': 60, 'Beta' : 76, 'Gamma' : 90, 'Delta' : 48 }

_dict = dict(sorted(_dict.items(), key=lambda item: item[1], reverse=True))

for item in _dict.items():
    print ("Key : " + item[0] + ", Value : " + str(item[1]))

Output

Key : Gamma, Value : 90
Key : Beta, Value : 76
Key : Alfa, Value : 60
Key : Delta, Value : 48

To sort the dictionary in ascending order based on keys, we would use item[ 0 ] in the lambda function.

Python3 : Sorting a dictionary by key in ascending order

_dict = { 'Craft': 10, 'Art' : 6, 'Talent' : 50, 'Skill' : 48, 'Luck': 100 }

_dict = dict(sorted(_dict.items(), key=lambda item: item[0]))

for item in _dict.items():
    print ("Key : " + item[0] + ", Value : " + str(item[1]))

Output

Key : Art, Value : 6
Key : Craft, Value : 10
Key : Luck, Value : 100
Key : Skill, Value : 48
Key : Talent, Value : 50

To sort the dictionary in descending order based on keys, we would use item[ 0 ] in the lambda function and set the reverse=True in the sorted function.

Python3 : Sorting a dictionary by key in descending order

_dict = { 'D': 1, 'Z' : 10, 'T' : 5, 'S' : 8, 'A': 0 }

_dict = dict(sorted(_dict.items(), key=lambda item: item[0], reverse=True))

for item in _dict.items():
    print ("Key : " + item[0] + ", Value : " + str(item[1]))

Output

Key : Z, Value : 10
Key : T, Value : 5
Key : S, Value : 8
Key : D, Value : 1
Key : A, Value : 0