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Data types in python

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Data types are one of the building blocks of python. And You can do a lot of things with data types!

Fact: In python, all data types are implemented as an object.

A data type is like a specification of what kind of data we would like to store in memory and python has some built-in data types in these categories:

  • Text type: str
  • Numeric types: int, float, complex
  • Sequence types: list, tuple, range
  • Mapping type: dict
  • Set types: set, frozenset
  • Boolean type: bool
  • Binary types: bytes, bytearray, memoryview

Now, let's demistify all these data types by using type() function to display the data type of the variable.

Text type

str

  • str stands for string in python used for storing text in python.
  • Strings can be written either in single quotes or double qoutes in python, hence your choice.

Example:

Alt Text

Output:

Hello, world!
<class 'str'>

Numeric types

int

  • int stands for integer used to store integers (positive and negative numbers).

Example:

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Output:

4
<class 'int'>

float

  • float stands for floating-point numbers (decimal point numbers)

Example:

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Output:

3.14
<class 'float'>

complex

  • Complex numbers have a real and imaginary part, which are each a floating point number.
  • Complex numbers can be written in two forms:
  1. real + (imag)j
  2. complex(real, imag)

Example:

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Output:

(5+10j)
<class 'complex'>

Sequence types

list

  • A list is data type where you can store a collection of data
  • A list can also contain different data types
  • A list is ordered and changeable and allows duplicate members

Example:

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Output:

['Captain America', 'Iron Man', 'Thor', 'Hulk', 'Black Widow', 'Hawkeye']
<class 'list'>

tuple

  • A tuple is data type where you can store a collection of data
  • A tuple can also contain different data types
  • A tuple is ordered and unchangeable and allows duplicate members

Example:

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Output:

('Captain America', 'Iron Man', 'Thor', 'Hulk', 'Black Widow', 'Hawkeye')
<class 'tuple'>

range

  • The range type represents an immutable (unchangable) sequence of numbers
  • Commonly used for looping a specific number of times in for loops.

Example:

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Output:

range(0, 10)
<class 'range'>

Mapping type

dict

  • dict stands for dictionary in python
  • Dictionaries are used to store data values in key:value pairs
  • A dictionary is a collection which is unordered, changeable and does not allow duplicates

Example:

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Output:

{'Learning': 'Programming', 'Language': 'Python', 'Day': 4}
<class 'dict'>

Set types

set

  • A set is data type where you can store a collection of data
  • A set can also contain different data types
  • A set is unordered and unindexed and allows no duplicate members

Example:

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Output:

{'Black Widow', 'Iron Man', 'Thor', 'Hawkeye', 'Hulk', 'Captain America'}
<class 'set'>

frozenset

  • frozenset data type can be created by frozenset() function
  • The frozenset() function accepts an iterable and returns an unchangeable frozenset object (which is like a set object, only unchangeable)

Example:

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Output:

frozenset({'cherry', 'banana', 'apple'})
<class 'frozenset'>

Boolean type

bool

  • bool stands for boolean in python
  • Booleans represent one of two values: True or False

Example:

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Output:

True
<class 'bool'>
False
<class 'bool'>

Binary types

bytes

  • bytes data type can be created in two forms:
  1. bytes() function
  2. prefix 'b'

Example:

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Output:

b'hello'
<class 'bytes'>
b'Hello'
<class 'bytes'>

bytearray

  • bytearray() function returns a bytearray object
  • It can convert objects into bytearray objects

Example:

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Output:

bytearray(b'\x00\x00\x00\x00')
<class 'bytearray'>

memoryview

  • memoryview() function returns a memory view object from a specified object

Example:

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Output:

<memory at 0x2b4f7a8a7408>
<class 'memoryview'>

Note

As you might have observed earlier, some data types can be also implemented using their constructors. This same technique can also be applied to every data type. Example:

Alt Text

Output:

Hello, World!
4
3.14
(5+10j)
['Captain America', 'Iron Man', 'Thor', 'Hulk', 'Black Widow', 'Hawkeye']
('Captain America', 'Iron Man', 'Thor', 'Hulk', 'Black Widow', 'Hawkeye')
range(0, 10)
{'Learning': 'Programming', 'Language': 'Python', 'Day': 4}
{'apple', 'cherry', 'banana'}
frozenset({'banana', 'cherry', 'apple'})
True
False
b'\x00\x00\x00\x00'
bytearray(b'\x00\x00\x00\x00')
<memory at 0x2b8346a29408>