Python Dictionary copy() Function with Examples

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Dictionary copy() Function in Python:

The copy() method makes a duplicate of the specified dictionary(copy).

Syntax:

dictionary.copy()

Parameters: This method doesn’t accept any parameters

Return Value:

This method gives you a shallow copy of the dictionary. It makes no changes to the original dictionary.

Examples:

Example1:

Input:

Given dictionary = {20: 'good', 30: 'morning', 40: 'btechgeeks'}

Output:

The given original dictionary is:
{20: 'good', 30: 'morning', 40: 'btechgeeks'}
The copied new dictionary is:
{20: 'good', 30: 'morning', 40: 'btechgeeks'}

Example2:

Input:

Given dictionary = {'hello': 100, 'btechgeeks': 200}

Output:

The given original dictionary is:
{'hello': 100, 'btechgeeks': 200}
The copied new dictionary is:
{'hello': 100, 'btechgeeks': 200}

Dictionary copy() Function with Examples in Python

Method #1: Using Built-in Functions (Static Input)

Approach:

  • Give the dictionary as static input and store it in a variable.
  • Copy the given dictionary into a new dictionary using the copy() function.
  • Store it in another variable.
  • Print the given original dictionary.
  • Print the copied new dictionary.
  • The Exit of the Program.

Below is the implementation:

# Give the dictionary as static input and store it in a variable.
gvn_dict = {20: 'good', 30: 'morning', 40: 'btechgeeks'}
# Copy the given dictionary into a new dictionary using the copy() function.
# Store it in another variable.
new_dict = gvn_dict.copy()
# Print the given original dictionary.
print("The given original dictionary is:")
print(gvn_dict)
# Print the copied new dictionary.
print("The copied new dictionary is:")
print(new_dict)

Output:

The given original dictionary is:
{20: 'good', 30: 'morning', 40: 'btechgeeks'}
The copied new dictionary is:
{20: 'good', 30: 'morning', 40: 'btechgeeks'}
Difference between Dictionary copy() Function , = Operator

When the copy() method is used, a new dictionary is created that contains a copy of the original dictionary’s references.
When the = operator is used, it creates a new reference to the original dictionary.

Approach:

  • Give the dictionary as static input and store it in a variable.
  • Copy the given dictionary into a new dictionary using the ‘=’ Operator.
  • Store it in another variable.
  • Remove all the elements from the new dictionary using the clear() function.
  • Print the given original dictionary.
  • Print the copied new dictionary.
  • The Exit of the Program.
# Give the dictionary as static input and store it in a variable.
gvn_dict = {'hello': 100, 'btechgeeks': 200}
# Copy the given dictionary into a new dictionary using the '=' Operator.
# Store it in another variable.
new_dict = gvn_dict
# Remove all the elements from the new dictionary using the clear() function.
new_dict.clear()
# Print the given original dictionary.
print("The given original dictionary is:")
print(gvn_dict)
# Print the copied new dictionary.
print("The copied new dictionary is:")
print(new_dict)

Output:

The given original dictionary is:
{}
The copied new dictionary is:
{}

Method #2: Using Built-in Functions (User Input)

Approach:

  • Take a dictionary and initialize it with an empty dictionary using dict() or {}.
  • Give the number of keys as user input using int(input()) and store it in a variable.
  • Loop till the given number of keys using for loop.
  • Inside the for loop scan the key and value as user input using input(), split() functions, and store them in two separate variables.
  • Initialize the key with the value of the dictionary.
  • Copy the given dictionary into a new dictionary using the copy() function.
  • Store it in another variable.
  • Print the given original dictionary.
  • Print the copied new dictionary.
  • The Exit of the Program.

Below is the implementation:

# Take a dictionary and initialize it with an empty dictionary using dict() or {}.
gvn_dict = {}
# Give the number of keys as user input using int(input()) and store it in a variable.
numb_of_kys = int(
    input('Enter some random number of keys of the dictionary = '))
# Loop till the given number of keys using for loop.
for p in range(numb_of_kys):
        # Inside the for loop scan the key and value as
    # user input using input(),split() functions
    # and store them in two separate variables.
    keyy, valuee = input(
        'Enter key and value separated by spaces = ').split()
    # Initialize the key with the value of the dictionary.
    gvn_dict[keyy] = valuee

# Copy the given dictionary into a new dictionary using the copy() function.
# Store it in another variable.
new_dict = gvn_dict.copy()
# Print the given original dictionary.
print("The given original dictionary is:")
print(gvn_dict)
# Print the copied new dictionary.
print("The copied new dictionary is:")
print(new_dict)

Output:

Enter some random number of keys of the dictionary = 2
Enter key and value separated by spaces = 100 hello
Enter key and value separated by spaces = 200 btechgeeks
The given original dictionary is:
{'100': 'hello', '200': 'btechgeeks'}
The copied new dictionary is:
{'100': 'hello', '200': 'btechgeeks'}