Python Data Type: String

Declaring String

a = "he said something"
b = "to her"
city = "America"
d = "her"

Accessing String

print(a)
print(a[0])
print(a[2:4])
print(a[-1])
print(a[-3:-1])
print(a + b) # Concatenation of string
print("He took", d, "to", city, "to spend the summer holidays")

String Formatter

# f-string
print(f"He took {d} to {city} to spend the summer holidays")

# format
print(
    "He took {0} to {1} to spend the summer holidays. Once again -He took {2} to {3} to spend the summer holidays"
.format(d, city, d, city))

# %-operator
print("He took %s to %s to spend summer holidays" % (d, city))

Python String Functions

# len
print(len(a))

# str- This function converts any data type into a string.
print(str(2 + 3j))

# lower() and upper()- These methods return the string in lowercase and uppercase, respectively.
print(a.lower())
print(a.upper())

# strip- It removes whitespaces from the beginning and end of the string.
x = " book"
print(x.strip())

# isdigit()- Returns True if all characters in a string are digits.
print(a.isdigit())

# isalpha()- Returns True if all characters in a string are characters from an alphabet.
print(a.isalpha())

# startswith(): It takes a string as an argument, and returns True is the string it is applied on begins with the string in the argument.
print(a.startswith("h")) # Prints True
print(a.startswith("H")) # Prints False

# endswith(): It takes a string as an argument, and returns True if the string it is applied on ends with the string in the argument.
print(a.endswith("g")) # Prints True
print(a.endswith("G")) # Prints False

# find(): It takes an argument and searches for it in the string on which it is applied. It then returns the index of the substring.
print(b.find("er")) # Prints 4

# If the string doesn’t exist in the main string, then the index it returns is 1.
print(a.find("er")) # Prints -1

# replace()- It takes two arguments. The first is the substring to be replaced. The second is the substring to replace with.
print(b.replace("er", "ER")) # Prints to hER

# split()-It takes one argument. The string is then split around every occurrence of the argument in the string.
a = a.split(" ")
print(a) # Prints ['he', 'said', 'something']
print(a[0]) # Prints 'he'
print(type(a)) # Prints class 'list'
b = b.split("e")
print(b) # Prints ['to h', 'r']

# join()
y = "*".join(["red", "green", "blue"])
print(y) # Prints red*green*blue

Python String Operations

print("hey" < "hi") # Prints True
print("ba" + "na" \* 2) # Prints ‘banana’
print("na" in "banana") # Prints True
print("Hey" is "Hi")