Finding Words Lengths in String using Python

Finding the lengths of individual words in a string is a common task in text processing and data analysis. Python provides several approaches to accomplish this, from simple loops to more advanced techniques using regular expressions and dictionaries.

Methods Used

• Using a loop and the split() function

• Using the map() function with len and split()

• Using the re.split() method from the re module

• Using a Dictionary to store word lengths

Using a Loop and the split() Function

This is the most straightforward approach. The split() function tokenizes the input text based on whitespace characters, and we iterate through the resulting words to calculate their lengths ?

Algorithm

• Split the input string into words using split()

• Initialize an empty list to store word lengths

• Loop through each word and calculate its length using len()

• Return the list of word lengths

Example

def find_word_lengths(input_string):
    words = input_string.split()
    word_lengths = []
    for word in words:
        word_lengths.append(len(word))
    return word_lengths

input_string = "Today feels like a productive day"
result = find_word_lengths(input_string)
print("The word lengths are:", result)

The word lengths are: [5, 5, 4, 1, 10, 3]

Using the map() Function with len and split()

The map() function provides a more concise approach by applying the len() function to each word in the split list ?

Example

def find_word_lengths(input_string):
    words = input_string.split()
    word_lengths = list(map(len, words))
    return word_lengths

input_string = "Hello my name is Rahul"
result = find_word_lengths(input_string)
print("The word lengths are:", result)

The word lengths are: [5, 2, 4, 2, 5]

Using the re.split() Method

Regular expressions provide more control over how text is split. The pattern r'\s+' matches one or more consecutive whitespace characters, making it robust for handling various whitespace patterns ?

Example

import re

def word_lengths(sentence):
    words = re.split(r'\s+', sentence)
    word_lengths_list = []
    
    for word in words:
        if word:  # Skip empty strings
            word_lengths_list.append(len(word))
    
    return word_lengths_list

sentence = "This is a sample sentence"
result = word_lengths(sentence)
print("Word lengths:", result)

Word lengths: [4, 2, 1, 6, 8]

Using a Dictionary to Store Word Lengths

This method creates a dictionary where each word is a key and its length is the corresponding value. This approach is useful when you need to look up the length of specific words ?

Example

def word_lengths(sentence):
    words = sentence.split()
    word_lengths_dict = {}
    
    for word in words:
        word_lengths_dict[word] = len(word)
    
    return word_lengths_dict

sentence = "This is how the length of words is calculated"
result = word_lengths(sentence)
print("Word lengths dictionary:", result)

Word lengths dictionary: {'This': 4, 'is': 2, 'how': 3, 'the': 3, 'length': 6, 'of': 2, 'words': 5, 'calculated': 10}

Comparison

Conclusion

Use map() with len for concise code, regular expressions for complex text patterns, and dictionaries when you need to map words to their lengths. For simple tasks, the basic loop approach offers the best readability.