Python Language Set: Difference between revisions

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s.remove('a')
s.remove('a')
</syntaxhighlight>
</syntaxhighlight>
Does not return anything.
Does not return anything, simply removes the element.
 
If the element does not exist, throws <code>KeyError: 'a'</code>.
 
=Convert to List=
=Convert to List=
<syntaxhighlight lang='py'>
<syntaxhighlight lang='py'>

Revision as of 04:40, 4 February 2023

Internal

TODO

Overview

Sets and the __hash__() Function

Sets and the __hash__() Function

Initialization

Literal initialization:

s = {1, 2, 3}

Set from a tuple:

s = set((1, 2, 3))

Set from a list:

s = set([1, 2, 3])

Set from a string:

s = set('ABC')
print(s)  # {'C', 'B', 'A'}

Shallow Copy

s = set()
s.add('a')
s2 = s.copy()

Remove an Element from a Set

s.remove('a')

Does not return anything, simply removes the element.

If the element does not exist, throws KeyError: 'a'.

Convert to List

s=set()
l=list(s)

frozenset()

The fronzenset() returns an immutable frozenset object initialized with the elements from a given iterable. frozenset objects can be used as dictionary keys.

If the iterable contains duplicate elements, they are ignored (the iterable is handled like a set):

f = frozenset(['a', 'b', 'c'])
f2 = frozenset(['a', 'b', 'c', 'a'])
assert f == f2