❮ Tuples
❯
- tuple
- ()
Create tuple
Tuple
- A tuple is a fixed-length immutable list. It cannot change its size or content.
- Can be accessed by index, using the slice notation.
- A tuple is denoted with parentheses: (1,2,3)
examples/lists/tuple.py
planets = ('Mercury', 'Venus', 'Earth', 'Mars', 'Jupiter', 'Saturn') print(planets) print(planets[1]) print(planets[1:3]) planets.append("Death Star") print(planets)
('Mercury', 'Venus', 'Earth', 'Mars', 'Jupiter', 'Saturn') Venus ('Venus', 'Earth') Traceback (most recent call last): File "/home/gabor/work/slides/python/examples/lists/tuple.py", line 6, in <module> tpl.append("Death Star") AttributeError: 'tuple' object has no attribute 'append'
List
- Elements of a list can be changed via their index or via the list slice notation.
- A list can grow and shrink using append and pop methods or using the slice notation.
- A list is denoted with square brackets: [1, 2, 3]
examples/lists/list.py
planets = ['Mercury', 'Venus', 'Earth', 'Mars', 'Jupiter', 'Saturn'] print(planets) print(planets[1]) print(planets[1:3]) planets.append("Death Star") print(planets)
['Mercury', 'Venus', 'Earth', 'Mars', 'Jupiter', 'Saturn'] Venus ['Venus', 'Earth'] ['Mercury', 'Venus', 'Earth', 'Mars', 'Jupiter', 'Saturn', 'Death Star']
Tuples are rarely used. There are certain places where Python or some module require tuple (instead of list) or return a tuple (instead of a list)
and in each place it will be explained. Otherwise you don't need to use tuples.
e.g. keys of dictionaries can be tuple (but not lists).