以下コード.
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import random | |
def sort_test(): | |
a = [random.random() for i in range(100)] | |
b = [random.random() for i in range(100)] | |
c = dict(zip(a, b)) | |
sorted(c, key=c.get) |
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import random | |
import operator | |
def sort_test(): | |
a = [random.random() for i in range(100)] | |
b = [random.random() for i in range(100)] | |
c = dict(zip(a, b)) | |
sorted(c.iteritems(), key=operator.itemgetter(1)) |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
import random | |
def sort_test(): | |
a = [random.random() for i in range(100)] | |
b = [random.random() for i in range(100)] | |
c = dict(zip(a, b)) | |
sorted(c.items(), key=lambda x:x[1]) |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
import random | |
def sort_test(): | |
a = [random.random() for i in range(100)] | |
b = [random.random() for i in range(100)] | |
c = dict(zip(a, b)) | |
d = zip(c.values(), c.keys()) | |
sorted(d) |
timeitで計測.
>>> import timeit
>>> timeit.timeit(stmt='get.sort_test()', setup='import get', number=10000)
0.6642911434173584
>>> timeit.timeit(stmt='itemgetter.sort_test()', setup='import itemgetter', number=10000)
0.6961650848388672
>>> timeit.timeit(stmt='zip.sort_test()', setup='import zip', number=10000)
0.6995840072631836
>>> timeit.timeit(stmt='lamb.sort_test()', setup='import lamb', number=10000)
0.7502970695495605
ただし
- zipの場合(value, key)のリストになる
- getの場合keyのリストになる(value値は返さない)
よく見かけるのはlambdaを使うものだが,同じ結果を得たかったらoperator.itemgetterを使うほうが少し早い.上位だけ取ってきたいときはgetが早いかも.
他にもやり方があるだろうか.