Python Program on Set Methods

In this article, we’ll explore two Python programs that delve into the world of sets, a powerful data structure in Python for handling unique elements. The first program focuses on various set operations, including union, clear, copy, pop, add, discard, and remove. The second program involves user input to create a set and then calculates the sum of its elements, showcasing the versatility of sets in Python.

Prerequisites

• Basic understanding of sets and their properties in Python.
• Familiarity with fundamental Python concepts, including variables, loops, and user input.
• Knowledge of essential set methods such as clear(), union(), copy(), pop(), add(), discard(), and remove().

Topic Explanation

Program 1 – begins with the initialization of two sets, myset1 and myset2, followed by a series of set operations. These operations include clearing a set, performing a union with another set (myset2), creating a copy of a set, popping an element, adding an element, and attempting to discard and remove non-existent elements. The program demonstrates essential set functionalities in Python.

Code:

# Creating two sets, myset1 and myset2, with some initial values
myset1 = {10, 20, 30, 40, 50, 60, 800}
myset2 = {100, 20, 50, 10, 600}

# Printing the contents of myset1
print(myset1)

# Clearing all elements from myset1
myset1.clear()

# Printing the union of an empty set (myset1) and myset2
# Note: The result is the same as myset2 since myset1 is empty
print(myset1.union(myset2))

# Creating a copy of myset1 and assigning it to myset2
myset2 = myset1.copy()

# Checking if myset1 is empty before attempting to pop an element
if myset1:
    # Removing an arbitrary element from myset1 using pop()
    # Note: Since sets are unordered, the specific element popped is not predictable
    myset1.pop()
else:
    print("Cannot pop from an empty set")

# Printing the modified contents of myset1 after popping an element
print(myset1)

# Adding the element 100 to myset1
myset1.add(100)

# Discarding the element 500 from myset1 if it exists
# Note: discard() does not raise an error if the element is not present
myset1.discard(500)

# Attempting to remove the element 500 from myset1
# Note: remove() raises a KeyError if the element is not present
# In this case, a KeyError will be caught and a message will be printed
try:
    myset1.remove(500)
except KeyError:
    print("Element 500 not found in the set")

# Printing the final contents of myset1 after the above operations
# Note: The element 500 was not added back due to the remove() operation
print(myset1)

# Creating an empty set named 'myset' using the set() constructor.
myset = set({})

# Taking user input for the limit of elements to be added to the set.
n = int(input("Enter the limit: "))

# Prompting the user to enter elements for the set in a loop.
print("Enter elements in the set:")
for i in range(n):
    # Taking user input for each element and converting it to an integer.
    x = int(input())
    
    # Adding the entered element to the set 'myset'.
    myset.add(x)

# Printing the sum of the elements in the set 'myset'.
print("Sum of elements in the set:", sum(myset))