Python: Index number of all lower case letters in a given string

Last update on May 24 2025 10:46:42 (UTC/GMT +8 hours)

Indices of Lowercase Letters

Write a Python program to get the index number of all lower case letters in a given string.

Sample Solution-1:

Python Code:

# Define a function 'test' that returns the indices of lowercase letters in a given text.
def test(text):
   # Use a list comprehension to find indices of lowercase letters.
   return [x for x in range(len(text)) if text[x].islower()]

# Provide a sample text "Python".
text = "Python"
# Print the original text.
print("Original string:", text)
# Print the indices of all lowercase letters in the sample text using the 'test' function.
print("Indices of all lower case letters of the said string:\n", test(text))

# Provide another sample text "JavaScript".
text = "JavaScript"
# Print the original text.
print("\nOriginal string:", text)
# Print the indices of all lowercase letters in the sample text using the 'test' function.
print("Indices of all lower case letters of the said string:\n", test(text))

# Provide one more sample text "PHP".
text = "PHP"
# Print the original text.
print("\nOriginal string:", text)
# Print the indices of all lowercase letters in the sample text using the 'test' function.
print("Indices of all lower case letters of the said string:\n", test(text))

Sample Output:

Original string: Python
Indices of all lower case letters of the said string:
 [1, 2, 3, 4, 5]
Original string: JavaScript
Indices of all lower case letters of the said string:
 [1, 2, 3, 5, 6, 7, 8, 9]
Original string: PHP
Indices of all lower case letters of the said string:
 []

Explanation:

Here is a breakdown of the above Python code:

• Test Function (test function):
• The "test()" function is defined to return the indices of lowercase letters in a given text.
• It uses a list comprehension to iterate through the text and find indices where each character is lowercase.

Flowchart:

Sample Solution-2:

Python Code:

# Define a function 'test' that returns the indices of lowercase letters in a given text.
def test(text):
   # Use list comprehension with enumerate to find indices of lowercase letters.
   return [index for index, element in enumerate(text) if element.islower()]

# Provide a sample text "Python".
text = "Python"
# Print the original text.
print("Original string:", text)
# Print the indices of all lowercase letters in the sample text using the 'test' function.
print("Indices of all lower case letters of the said string:\n", test(text))

# Provide another sample text "JavaScript".
text = "JavaScript"
# Print the original text.
print("\nOriginal string:", text)
# Print the indices of all lowercase letters in the sample text using the 'test' function.
print("Indices of all lower case letters of the said string:\n", test(text))

# Provide one more sample text "PHP".
text = "PHP"
# Print the original text.
print("\nOriginal string:", text)
# Print the indices of all lowercase letters in the sample text using the 'test' function.
print("Indices of all lower case letters of the said string:\n", test(text))

Sample Output:

Original string: Python
Indices of all lower case letters of the said string:
 [1, 2, 3, 4, 5]
Original string: JavaScript
Indices of all lower case letters of the said string:
 [1, 2, 3, 5, 6, 7, 8, 9]
Original string: PHP
Indices of all lower case letters of the said string:
 []

Explanation:

Here is a breakdown of the above Python code:

• Test Function (test function):
• The "test()" function is defined to return the indices of lowercase letters in a given text.
• It uses a list comprehension to iterate through the text and find indices where each character is lowercase.

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python program to find the indices of all lowercase letters in a string using enumerate.
• Write a Python program to return a list of positions where characters in a string are lowercase.
• Write a Python program to identify and list the index positions of all lowercase alphabetic characters in a given string.
• Write a Python program to scan a string and output the indices of characters that are in lowercase.

Go to:

• Python Basic Exercises Home ↩
• Python Exercises Home ↩

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Python Code Editor:

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