String Manipulation

Slicing, concatenation, formatting, and the most useful string methods.

String Basics

Strings in Python can be enclosed in single ' or double " quotes, or triple quotes for multi-line text:

s1 = 'Hello'
s2 = "World"
s3 = """This is
a multi-line
string."""

Indexing and Slicing

word = "Python"
print(word[0])      # P  (first character)
print(word[-1])     # n  (last character)
print(word[0:3])    # Pyt
print(word[::-1])   # nohtyP (reversed)

Useful String Methods

s = "  hello, world!  "
print(s.strip())        # "hello, world!"
print(s.upper())        # "  HELLO, WORLD!  "
print(s.lower())        # "  hello, world!  "
print(s.replace("world", "Python"))
print(s.split(","))     # ['  hello', ' world!  ']
print(s.count("l"))    # 3
print(s.find("world")) # 9
print(s.startswith("  h"))  # True

String Formatting (f-strings)

name = "Charlie"
score = 87.5
grade = "B+"
print(f"Student: {name:<10} Score: {score:6.1f} Grade: {grade}")
# Student: Charlie    Score:   87.5 Grade: B+