Suppose that I have a list lst of some objects.
What value of an object is used to perform sorted(lst) if key function is not provided? Is it hash or some id?
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it depends on the object type. This is described in their respective classes (how they implement comparison).Ma0– Ma02018-01-25 09:42:44 +00:00Commented Jan 25, 2018 at 9:42
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2 Answers
when no key is provided, sort uses exclusively the < operator, as demonstrated in this example:
class A:
def __init__(self,a):
self.a = a
def __lt__(self,other):
return self.a < other.a
def __repr__(self):
return str(self.a)
lst = [A(12),A(10),A(44)]
print(sorted(lst))
here I get:
[10, 12, 44]
sort used the defined __lt__ (less than) operator internally, only, not equal not superior. Sorting is only performed with < operator.
(commenting the __lt__ operator leads to TypeError: unorderable types: A() < A())
answered Jan 25, 2018 at 9:47
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Python sort()
This method sorts the list in place, using only < comparisons between items. Exceptions are not suppressed - if any comparison operations fail, the entire sort operation will fail (and the list will likely be left in a partially modified state).
Refer: list.sort()
1 Comment
dsgdfg
lst.sort() equal to [1,11,111,2,3,33,333] awesome sort !