Python program to generate a list of alphabets in lexical order

Lexical order can be used in various applications like sorting algorithms, organizing data in dictionaries or indexes, and string comparisons. In this article, we will explain that how to generate a list of alphabets in lexical order. Lexical order is also known as lexicographic or dictionary order. The words are arranged according to the alphabetical order of their components or letters. In English, there are 26 letters, the lexical order will be followed the traditional ordering of the letters from 'a' to 'z'. Here, we are using various methods to accomplish this task. It will also demonstrate a suitable example.

When we are placing words or symbols in lexical order, by comparing character by character and the indexing starts from the leftmost position. In order to get the correct position of a word or symbol the ordering is calculated by the first differing character encountered while doing the comparison. When all characters are similar to a certain point, the shorter word comes before the longer one.

For example, consider the following list of words in lexical order −

• apple

• baby

• banana

• boy

• car

• cat

• dip

• dog

In the above-mentioned list, we can see clearly that the words are arranged based on the alphabetical order of their first characters. 'apple' comes before 'baby' because the character 'a' comes before the character 'b' in the alphabet. Similarly, 'car' comes before 'cat' because 'r' comes before 't'. When two words have a similar starting character then the comparison will start to move to the next character until a difference is found or one word ends. The lexical order is a fundamental concept used in various applications as said earlier.

Generating a List of Alphabets in Lexical Order

Code Explanation and Design Steps −

• Step 1 − Open Jupyter Notebook in the Anaconda prompt and start writing the code in its cell.

• Step 2 − We use a for loop to iterate over the range from 0 to 25 which will correspond to the 26 letters of the English alphabet.

• Step 3 − Inside the loop, chr() function is being utilized to convert the ASCII value of every letter to its corresponding character.

• Step 4 − Take as an example, 97 is the ASCII value of lowercase ‘a’, therefore by adding the loop index i to it we can generate the characters in lexical order.

• Step 5 − The append() method adds each character to the alphabet list.

• Step 6 − Print the alphabet.

Example 1

Code for generation of a list of alphabets in lexical order −

# initialize list
alphabet = []
for i in range(26):
   alphabet.append(chr(ord('a') + i))

print(alphabet)

Output

['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z']

Code Explanation and Design Steps

• Step 1 − Open Jupyter Notebook in the Anaconda prompt and start writing the code in its cell.

• Step 2 − Import the string’ module from Python standard library.

• Step 3 − ‘string’ module contains ‘ascii_lowercase’ constant string that shows all the lowercase letters of the English dictionary.

• Step 4 − Use the ‘list()’ function to convert it. We obtain the desired result.

Example 2

# import the required module
import string

alphabet = list(string.ascii_lowercase)
print(alphabet)

Output

['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z']

This program can be used in many applications when the requirement arises to work with or manipulate the sequence of alphabets. In the case of sorting strings, this program can be used as a basis for sorting a list of strings in lexical order. By applying a sorting algorithm, we can arrange a list of strings in alphabetical order using comparing the first characters of the strings.

Another use of this program is to generate passwords with certain patterns. This program can be extended by additional logic and constraints to generate passwords on the basis of specific patterns. Just a few examples are being demonstrated for your understanding purposes but we have many other use of this program such as word games and puzzles and character frequency analysis.

Conclusion

This article uses different approaches to show how to generate a list of alphabets in a lexical order. Python code for all methods is given in this article with its code explanation and output as well.