Python Strings

Strings

Slice.

my_str = "Hello"
sliced_str = my_string[1:3] # "el"

Concatenate.

my_str = "Hello"
concatenated_str = my_string + ", world!" # "Hello, world!"

Repeat.

my_str = "Hello"
repeated_str = my_string * 2 # "HelloHello"

Split.

# Split by whitespace (default).
my_str = "Hello World!"
split_by_whitespace = my_str.split() # ["Hello", "World"]

# Split by delimiter.
my_str = "alpha,beta,gamma"
split_by_delimeter = my_str.split(",") # ["alpha", "beta", "gamma"]

# Break a single word into a list.
my_word = "Hello"
my_list = list(my_word) # ["H", "e", "l", "l", "o"]

# Split by newlines.
my_str = "line 1\nline 2\nline 3"
multiline_list = my_str.splitlines() # ["line 1", "line 2", "line 3"]

Find the first occurrence (i.e. index) of a character in a string.

my_str = "Hello"

# Check existence first.
found_in_str = "l" in my_str.lower() # True
index = my_str.index("l") if found_in_str else -1 # Returns: 2

Character Operations

Find the ASCII ordinal number of a character.

print(ord("A"))  # 65

Convert an ASCII ordinal number to its character.

print(chr(65))  # "A"
print(chr(ord("A") + 1)) # "B"

Determine types of characters.

print("C".isalpha())     # True (all alpha chars)
print("C++".isalpha())   # False
print("239".isdigit())   # True (all numeric chars)
print("C239".isdigit())  # False
print("C98".isalnum())   # True (all alphanumeric chars)
print("C98++".isalnum()) # False
print("c".islower())     # True (all lowercase)
print("cRx".islower())   # False