Python: Count Words in Each Line of a Text File (Solved)

Practice Question 13

In this question, we will learn how to write a function that reads a file and displays the word count for every single line. This is a great way to analyze the structure and density of a document.

The Logic (How it works)

Before writing the code, let us first understand the logic behind the solution.

To solve this, we need to treat the file as a list of sentences and then break each sentence into words. Here is the teacher’s breakdown:

• Read Line by Line: We use f.readlines() to get a list where every item is one line from the file.

• The Outer Loop: We go through each line one by one using a for loop.

• The Split Strategy: Inside the loop, we use line.split(). This breaks the current line into a list called wordlist.

• The Count: We use len(wordlist) to find out how many words are in that specific line.

• The Display: We use a counter line_no to show which line we are currently describing.

Let’s Code as per the above logic :

def lineWiseWordCount():
    f = open("records.txt", "r")
    linelist = f.readlines()
    
    line_no = 1
    for line in linelist:
        wordlist = line.split()
        count = len(wordlist)
        print("Line ", line_no, ":", count, "words")
        line_no += 1
            
    f.close()

# To call the function:
lineWiseWordCount()

Important Notes for Students

Pay attention to these small details to ensure your logic is “Board Exam” ready:

1. Handling Empty Lines: If a line is empty (just a newline), line.split() will return an empty list []. The len() function will return 0, so your output will correctly say “0 words.”

2. The line_no Counter: Notice that we initialize line_no = 1 outside the loop and increment it inside the loop. This ensures we don’t start counting lines from zero, which is more user-friendly.

3. Why readlines()? This method is ideal when you need to know exactly where one line ends and another begins.

Teacher’s Secret Tip for Exams:

If the question asks you to only count lines that have more than 10 words, simply wrap the print statement in an if condition: if count > 10: print(...). The rest of your logic stays exactly the same!

Want to practice more? If you found this helpful, I have compiled a full list of 30 practice problems just like this one. Each question focuses on a different logic to help you become a pro at File Handling.

Click here to view the full 30-Question Practice Set

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