8.5. Nested Recap

8.5.1. What is an Object?

  • Basic types are objects

  • Iterable are objects too

  • Everything is an object

  • tuple.mro()

  • list.mro()

  • set.mro()

>>> tuple.mro()
[<class 'tuple'>, <class 'object'>]
>>> list.mro()
[<class 'list'>, <class 'object'>]
>>> set.mro()
[<class 'set'>, <class 'object'>]

8.5.2. Append vs. Extend

>>> from pprint import pprint
>>> data = [1, 2, 3]
>>> data.extend([4, 5, 6])
>>>
>>> data
[1, 2, 3, 4, 5, 6]
>>> data = [1, 2, 3]
>>> data.append([4, 5, 6])
>>>
>>> data
[1, 2, 3, [4, 5, 6]]

Append elements using list.append():

>>> result = [
...     ('Mark', 'Watney'),
...     ('Melisa', 'Lewis'),
...     ('Rick', 'Martinez'),
... ]
>>>
>>> data = ('Alex', 'Vogel')
>>> result.append(data)
>>>
>>> pprint(result, width=30)
[('Mark', 'Watney'),
 ('Melisa', 'Lewis'),
 ('Rick', 'Martinez'),
 ('Alex', 'Vogel')]

Append elements using list.extend():

>>> result = [
...     ('Mark', 'Watney'),
...     ('Melisa', 'Lewis'),
...     ('Rick', 'Martinez'),
... ]
>>>
>>> data = ('Alex', 'Vogel')
>>> result.extend(data)
>>>
>>> pprint(result, width=30)
[('Mark', 'Watney'),
 ('Melisa', 'Lewis'),
 ('Rick', 'Martinez'),
 'Alex',
 'Vogel']

8.5.3. Use Case - 1

  • One dimensional (1D) structure - vector

>>> data = [1, 2, 3]

Is equivalent to:

>>> obj1 = 1
>>> obj2 = 2
>>> obj3 = 3
>>>
>>> data = [obj1, obj2, obj3]

8.5.4. Use Case - 2

  • Two dimensional (2D) structure - matrix

>>> data = [
...      [1, 2, 3],
...      [4, 5, 6],
...      [7, 8, 9],
... ]

Is equivalent to:

>>> obj1 = [1, 2, 3]
>>> obj2 = [4, 5, 6]
>>> obj3 = [7, 8, 9]
>>>
>>> data = [obj1, obj2, obj3]

8.5.5. Assignments