Python Program to Capitalize Specific Character in String

In this article, you will learn and get code in Python, to capitalize any specific character (entered by user) in a string (entered by user).

For example, if the given string is fresherearth, then the string after capitalizing the character say c becomes fresherearth

Capitalize Specific Character in String

This program receives a string and a character from user to capitalize the given character in given string as shown in the program given below:

print("Enter the String:")
text = str(input())
print("Enter a Character:")
char = input()
textLen = len(text)
for i in range(textLen):
    if char==text[i]:
        if text[i]>='a' and text[i]<='z':
            ascVal = ord(text[i])
            ascVal = ascVal-32
            ascVal = chr(ascVal)
            index = i
            text = text[:index] + ascVal + text[index+1:]
print("\nThe New String is:")
print(text)

Here is its sample run:

Now supply any string say welcome to fresherearth and a character say e to capitalize all e in given string as shown in the snapshot given below:

The dry run of above program with same user input as provided in sample run goes like:

• Initial values, text = welcome to fresherearth (entered by user), and char = e (also entered by user)
• The entered string stored in text in a way that:
  • text[0]=w
  • text[1]=e
  • text[2]=l
  • and so on upto
  • text[22]=r
• Using len(), the length of text gets initialized to textLen. So textLen=23
• Now the execution of for loop begins. Since range() contains only one value, therefore the value of i stars with 0
• Because 0 is less than textLen, therefore program flow goes inside the loop and the condition (of if) char==text[i] or e==text[0] or e==w evaluates to be false, therefore program flow does not goes inside the if's body, rather the value of i gets incremented by 1. So i=1
• Again the value of i is less than textLen, therefore program flow again goes inside the loop and evaluates the condition of if
• In this way, the execution continues, until the value of i becomes equal to textLen
• When the condition of if evaluates to be true, then we've checked whether the character at current index of text[] is greater than or equal to a and less than or equal to z or not
• If this condition gets satisfies, then only we've to capitalize the character. Otherwise continue to check for next character. Because, only alphabets (a-z) can be capitalized
• The ord returns Unicode (ASCII value) of character. And the chr() returns the character corresponding to its Unicode

Note - The text[:2] referred to elements from starting (0^th) to second (1^st) index. Whereas text[2:] referred to elements from second (2^nd) index to last.

You can also replace (reverse) the following block of code:

if char==text[i]:
    if text[i]>='a' and text[i]<='z':

with

if text[i]>='a' and text[i]<='z':
    if char==text[i]:

Modified Version of Previous Program

This is the modified version of previous program. The end is used to skip printing of automatic newline.

print(end="Enter the String: ")
text = str(input())
print(end="Enter the Character: ")
char = input()
if char>='A' and char<='Z':
    ascVal = ord(char)
    ascVal = ascVal + 32
    ascVal = chr(ascVal)
    char = ascVal
textLen = len(text)
for i in range(textLen):
    if char==text[i]:
        if text[i]>='a' and text[i]<='z':
            ascVal = ord(text[i])
            ascVal = ascVal-32
            ascVal = chr(ascVal)
            index = i
            text = text[:index] + ascVal + text[index+1:]
print("\nThe New String is: " + text)

Here is its sample run with user input, fresherearth

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