37. Advanced String Handling Pt. 1

• Using loops and comparisons, you can do some pretty nifty things with strings of characters
• Performing comparisons is much more powerful when you use loops to inspect each individual character
• Note the in operator works on strings as well as lists

#Declare a string
string = "John Henry was a desperate little man."

#Loop through each letter in the string, and print with a space after each
for letter in string:
    print(letter)

#Quick length calculation
string_length = len(string)
print("String Length:",string_length)

#Set counters to 0
vowels = 0
others = 0

#Loop string and count vowels
for letter in string:

    #if a vowel...
    if letter in "aeiuo":
        vowels += 1

    #if not a vowel
    else: 
        others += 1

#Print the total counts once complete
print("Vowels: ",vowels)
print("Others: ",others)

Tasks

1. Type in the code and test it works
2. Modify the program to count uppercase and lowercase letters
3. Modify the program to count punctuation and spaces
4. Save and label your code

Extension Task

The break command allows you to exit a for loop at any time. You can use this to modify your program to print an error and quit if a number is detected in the input string.