14. Lektion: Variablen vielfalt.extend()

Inhaltsverzeichnis

1 Zuweisungsvielfalt
2 Navigation

Zuweisungsvielfalt

Python ermöglicht es mehreren Variablen gleichzeitig Werte zuzuweisen.

Mehrfach Zuweisung eines Wertes:

>>> a = b = c = 42
>>> print(a, b, c)
    42 42 42
>>>

Mehrfachzuweisung verschiedener Werte:

>>> a, b, c = 1, 2, 3
>>> print(a, b, c)
    1 2 3
>>>

Mehrfachzuweisung aus einer Liste:

>>> a, b, c = [10, 20, 30]
>>> print(a, b, c)
    10 20 30
>>> z = [1, 2, 3]
>>> a, b, c = z
>>> print(a, b, c)
    1 2 3
>>>

Mehrfachzuweisung aus einer Liste mit mehr Werten:

>>> z = [1, 2, 3, 4, 5]
>>> a, b, c = z
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    ValueError: too many values to unpack (expected 3)
>>> a, b, *c = z
>>> print(a, b, c)
    1 2 [3, 4, 5]
>>> 
>>> z = [1, 2, 3]
>>> a, b, *c = z
>>> print(a, b, c)
    1 2 [3]
>>>

- x, y, z = [1, 2, 3]
- 2) Tuple Unpacking (with & without *)

person = ['tom', 5, 'male']

name, age, gender = person
# name='tom', age=5, gender='male'

We can use tuple unpacking to assign multiple variables in one line.

letters = ['A', 'B', 'C', 'D', 'E', 'F', 'G']

first, second, *others = letters
# first='A', second='B'
# letters = ['C', 'D', 'E', 'F', 'G']

We can add a * character in front of variables to signify that it should contain everything else that hasn’t been unpacked.

https://medium.com/@sarperismetmakas/10-python-shortcuts-6f5c62c53bb1