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Maksym
Maksym

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Data types in Python

#python #webdev #computerscience

Python has several built-in data types that serve different purposes. Here's a comprehensive breakdown:

Numeric Types

Integer (int)

  • Whole numbers without decimal points
  • Can be positive, negative, or zero
  • No size limit (limited only by available memory) 
age = 25
temperature = -5
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Float (float)

  • Numbers with decimal points
  • Uses double precision 
price = 19.99
pi = 3.14159
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Complex (complex)

  • Numbers with real and imaginary parts 
z = 3 + 4j
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Sequence Types

String (str)

  • Ordered collection of characters
  • Immutable (cannot be changed after creation)
  • Enclosed in quotes (single, double, or triple) 
name = "Alice"
message = 'Hello World'
multiline = """This is a
multiline string"""
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List (list)

  • Ordered collection of items
  • Mutable (can be modified)
  • Can contain different data types 
fruits = ["apple", "banana", "orange"]
mixed = [1, "hello", 3.14, True]
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Tuple (tuple)

  • Ordered collection of items
  • Immutable
  • Defined with parentheses 
coordinates = (10, 20)
colors = ("red", "green", "blue")
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Mapping Type

Dictionary (dict)

  • Unordered collection of key-value pairs
  • Keys must be immutable and unique
  • Values can be any data type 
person = {"name": "John", "age": 30, "city": "New York"}
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Set Types

Set (set)

  • Unordered collection of unique items
  • Mutable
  • No duplicate values allowed 
unique_numbers = {1, 2, 3, 4, 5}
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Frozen Set (frozenset)

  • Immutable version of set 
immutable_set = frozenset([1, 2, 3, 4])
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Boolean Type

Boolean (bool)

  • Represents True or False
  • Subclass of int (True = 1, False = 0) 
is_sunny = True
is_raining = False
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None Type

None (NoneType)

  • Represents absence of value
  • Often used as default value or placeholder 
result = None
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Key Characteristics

Mutable vs Immutable:

  • Mutable: list, dict, set (can be modified)
  • Immutable: int, float, str, tuple, frozenset, bool, None (cannot be modified)

Type Checking:

type(42)        # <class 'int'>
isinstance(42, int)  # True
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Type Conversion:

int("123")      # 123
str(456)        # "456"
list("hello")   # ['h', 'e', 'l', 'l', 'o']
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Understanding these data types is fundamental since they determine what operations you can perform on your data and how Python stores and manipulates information in memory.

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