Introduction to Python Data Types
Python Data Types
Python provides several built-in data types that are used to represent different kinds of information.
Here are some of the commonly used data types in Python:
Numeric Types
int:
Represents integers (whole numbers) like 5, -10, 100.float:
Represents floating-point numbers with decimal values like 3.14, -2.5, 0.75.complex:
Represents complex numbers in the forma + bj
, wherea
andb
are real numbers andj
represents the imaginary unit.
# int
x = 5
y = -10
# float
pi = 3.14
temperature = -2.5
# complex
z = 2 + 3j
w = -1j
Text Type:
str:
Represents strings of characters enclosed in single quotes ('
) or double quotes ("
). Strings can contain letters, digits, symbols, and whitespace.
# str
name = 'John'
message = "Hello, World!"
Boolean Type
bool:
Represents a boolean value that can be eitherTrue
orFalse
. Boolean values are used in conditional statements and logical operations.
# bool
is_true = True
is_false = False
Sequence Types
list:
Represents an ordered and mutable collection of items. Lists are enclosed in square brackets ([]
) and can contain elements of different types.tuple:
Represents an ordered and immutable collection of items. Tuples are enclosed in parentheses (()
) and can contain elements of different types.range:
Represents an immutable sequence of numbers. Ranges are commonly used in loops and generate a sequence of numbers based on the specified start, stop, and step values.
# list
fruits = ['apple', 'banana', 'orange']
numbers = [1, 2, 3, 4, 5]
# tuple
coordinates = (10, 20)
person = ('John', 25)
# range
countdown = range(10) # Generates numbers from 0 to 9
Mapping Type
dict:
Represents an unordered collection of key-value pairs. Dictionaries are enclosed in curly braces ({}
) and are used to store and retrieve values based on unique keys.
# dict
student = {'name': 'Alice', 'age': 20}
scores = {'math': 90, 'science': 85, 'history': 92}
Set Types
set:
Represents an unordered collection of unique elements. Sets are enclosed in curly braces ({}
) and can be created by passing iterable objects or using theset()
constructor.frozenset:
Similar to sets, frozensets represent an immutable collection of unique elements.
# set
unique_numbers = {1, 2, 3, 4, 5}
# frozenset
immutable_set = frozenset({1, 2, 3})
How to check data types
You can use the built-in type()
function to check the data type of a variable or a value.
The type()
function returns the type of the specified object.
Here's how you can use it:
x = 5
y = 3.14
name = "John"
is_true = True
fruits = ['apple', 'banana', 'orange']
student = {'name': 'Alice', 'age': 20}
print(type(x)) # <class 'int'>
print(type(y)) # <class 'float'>
print(type(name)) # <class 'str'>
print(type(is_true)) # <class 'bool'>
print(type(fruits)) # <class 'list'>
print(type(student)) # <class 'dict'>
In the above example:
- The
type()
function is used to determine the data type of each variable. The output shows the respective data types enclosed in<class '...'
>.
You can also use the isinstance()
function to check if an object belongs to a specific data type. It returns True
if the object is an instance of the specified type, and False
otherwise.
As an example:
x = 5
if isinstance(x, int):
print("x is an integer")
else:
print("x is not an integer")
In this case:
- The
isinstance()
function checks ifx
is an instance of theint
type and prints the corresponding message.