Dict Functions

Various built-in functions are available in Python which helps to perform multiple operations on dictionary. Below are the top must know dict methods in python

Length Function

This function helps to return the length of the given dictionary data items

#Length Function
language_dict = {
    1 : "Python",
    2 : "Java",
    3 : "JavaScript",
    4 : "C++"
}

print("The length of the given dict datasets is : ")
print(len(language_dict))

Output

The length of the given dict datasets is : 
4

Clear Method

Clear method helps to remove all the elements in given dict data items and make it as empty dict

#Clear Method
language_dict = {
    1 : "Python",
    2 : "Java",
    3 : "JavaScript",
    4 : "C++"
}

print("The clear method removes all data...")
language_dict.clear()
print(language_dict)

Output

The clear method removes all data...
{}

Get Method

Get method helps to get the value for that specified key from given dict data items

#Get Method
language_dict = {
    1 : "Python",
    2 : "Java",
    3 : "JavaScript",
    4 : "C++"
}

print("The get method retrieves the key's value...")
print(language_dict.get(3))

Output

The get method retrieves the key's value...
JavaScript

PopItem Method

Popitem method helps to remove the last key value pair from dict by default

#PopItem Method
language_dict = {
    1 : "Python",
    2 : "Java",
    3 : "JavaScript",
    4 : "C++"
}

print("The popitem method removes the last item from dict...")
language_dict.popitem()
print(language_dict)

Output

The popitem method removes the last item from dict...
{1: 'Python', 2: 'Java', 3: 'JavaScript'}

Copy Method

Copy method helps to copy the given dict to another variable

#Copy Method
language_dict = {
    1 : "Python",
    2 : "Java",
    3 : "JavaScript",
    4 : "C++"
}

print(id(language_dict))
print("Making a copy of dict data in different memory location")
language_dict_copy = language_dict.copy()
print(language_dict_copy)
print(id(language_dict_copy))

Output

140312120052864
Making a copy of dict data in different memory location
{1: 'Python', 2: 'Java', 3: 'JavaScript', 4: 'C++'}
140312120052928

Fromkeys Method

Fromkey function helps to create dictionary from the given keys list and value

#Fromkey Method
language_keys = {1, 2, 3, 4}
language_values = "Python"

print("Creation of a dict using the fromkey method")
language_dict = dict.fromkeys(language_keys, language_values)
print(language_dict)

Output

Creation of a dict using the fromkey method
{1: 'Python', 2: 'Python', 3: 'Python', 4: 'Python'}

SetDefault Method

setDefault helps to return the given key's value as default. if the key is not available none will returns

#SetDefault Method
language_dict = {
    1 : "Python",
    2 : "Java",
    3 : "JavaScript"
}

#SetDefault returns the value of the corresponding key
result=language_dict.setdefault(3)
print(result)

#None will return if the key is not available
result=language_dict.setdefault(5)
print(result)

#Create new pair, if we pass value also as a parameter
result=language_dict.setdefault(4,"C++")
print(language_dict)
print(result)

Output:

JavaScript
None
{1: 'Python', 2: 'Java', 3: 'JavaScript', 5: None, 4: 'C++'}
C++