How to Add Polynomials in Python

Polynomials are expressions that include variables and coefficients. These variables are of different degrees and in Python, we can easily perform various operations on them, such as addition, subtraction, multiplication, etc. Today, we will mainly focus on how to add polynomials in Python.

Step 1: Set up Python

First, ensure Python is successfully installed on your system. If Python is not installed, you can download and install it from the official Python website. Make sure to install Python 3 as Python 2 is deprecated.

Step 2: Write Functions for Polynomial Addition

Next, open your favorite Python IDE and start by defining two separate sets of polynomials to be processed for addition. These polynomials are generally expressed in list format.

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poly1 = [2, 0, 5, 7]
poly2 = [3, 4, 2]

In the above code, poly1 represents 2x^3 + 0x^2 + 5x + 7, and poly2 represents 3x^2 + 4x + 2. Notice that each coefficient is positioned at its corresponding index in the list.

Step 3: Process the Addition of Polynomials

Now, we will add these polynomials. Python’s built-in zip_longest() method from the itertools module can be used to achieve this. This function fills in missing values with zeros when the lengths of polynomials are not equal, thus making the addition process smoother.

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from itertools import zip_longest
 
def add(poly1, poly2):
  return [a+b for a, b in zip_longest(poly1, poly2, fillvalue = 0)]
 
result = add(poly1, poly2)

Step 4: Display the Result of Addition

The final step involves printing out the resulting sum of polynomials, as follows:

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print(result)

Full Python Code

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from itertools import zip_longest
 
# Define the polynomials
poly1 = [2, 0, 5, 7]
poly2 = [3, 4, 2]
 
# Function to add polynomials
def add(poly1, poly2):
  return [a+b for a, b in zip_longest(poly1, poly2, fillvalue = 0)]
 
# Perform addition
result = add(poly1, poly2)
 
# Display the result
print(result)

Code Output

[5, 4, 7, 7]

The output represents the coefficients of the polynomial 5 + 4x + 7x^2 + 7*x^3, which is the result of adding poly1 and poly2.

Conclusion

And there you have it! You’ve successfully added polynomials in Python. This tutorial has hopefully shed light on one of the ways to perform mathematical operations in Python, leveraging the power of its built-in functions. Happy coding!