Python: Unique words and frequency from a given list of strings

Last update on March 28 2025 13:02:16 (UTC/GMT +8 hours)

21. Unique Words and Frequency Count from a List of Strings

Write a Python program to find all the unique words and count the frequency of occurrence from a given list of strings. Use Python set data type.

Sample Solution:

Python Code:

# Define a function 'word_count' that takes a list of words as input and returns a dictionary of word counts.
def word_count(words):
    # Create a set 'word_set' to remove duplicate words from the input list.
    word_set = set(words)
    
    # Create an empty dictionary 'word_counts' to store word counts.
    word_counts = {}
    
    # Iterate over the unique words in 'word_set'.
    for word in word_set:
        # Count the occurrences of each word in the input list and store the count in 'word_counts'.
        word_counts[word] = words.count(word)
    
    # Return the 'word_counts' dictionary.
    return word_counts

# Create a list 'words' with words of various colors.
words = ['Red', 'Green', 'Red', 'Blue', 'Red', 'Red', 'Green']

# Call the 'word_count' function with the 'words' list and print the word counts.
print(word_count(words)) 

Sample Output:

{'Red': 4, 'Blue': 1, 'Green': 2}

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python program to extract unique words from a list of strings using a set and then count their frequencies in the list.
• Write a Python program to use collections.Counter on a set derived from a list of strings to display word frequency.
• Write a Python program to iterate over a list of strings and build a frequency dictionary for unique words.
• Write a Python program to convert a list of strings into a set of unique words and then map each word to its count using a dictionary comprehension.

Python Code Editor:

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