Python has several built-in data types that can be used to store different kinds of information. These data types include:
Numbers: Python has two types of numbers: integers and floating-point numbers. Integers are whole numbers (e.g., 1, 2, 3) and floating-point numbers are numbers with a decimal point (e.g., 1.0, 2.5, 3.14). You can use the int() and float() functions to convert numbers from one type to another.
x = 10 # integer
y = 20.5 # floating-point number
print(type(x)) # Output: <class 'int'>
print(type(y)) # Output: <class 'float'>
# You can use the int() function to convert a floating-point number to an integer
z = int(y)
print(z) # Output: 20
print(type(z)) # Output: <class 'int'>
# You can use the float() function to convert an integer to a floating-point number
a = float(x)
print(a) # Output: 10.0
print(type(a)) # Output: <class 'float'>
Strings: Strings are sequences of characters and are used to represent text. You can use single quotes (‘) or double quotes (“) to define a string. For example: "Hello, World!" or 'Hello, World!'. You can use the len() function to find the length of a string.
x = "Hello, World!" y = 'Hello, World!' print(len(x)) # Output: 13 print(len(y)) # Output: 13 # You can use single quotes inside a string defined with double quotes and vice versa x = "Hello, 'John'" y = 'Hello, "John"' print(x) # Output: Hello, 'John' print(y) # Output: Hello, "John"
Lists: Lists are ordered sequences of objects. You can define a list by enclosing a comma-separated sequence of objects in square brackets ([]). For example: [1, 2, 3] or ['apple', 'banana', 'cherry']. You can access the elements of a list using their indexes (e.g., my_list[0] returns the first element of the list). You can use the len() function to find the length of a list.
# Define a list x = [1, 2, 3] # Access the elements of the list using their indexes print(x[0]) # Output: 1 print(x[1]) # Output: 2 print(x[2]) # Output: 3 # You can also use negative indexes to access the elements of the list from the end print(x[-1]) # Output: 3 print(x[-2]) # Output: 2 print(x[-3]) # Output: 1 # You can use the len() function to find the length of the list print(len(x)) # Output: 3 # You can modify the elements of a list by assigning new values to them x