本文实例讲述了Python中map和列表推导效率比较。分享给大家供大家参考。具体分析如下:
直接来测试代码吧:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
|
#!/usr/bin/env python # -*- coding: utf-8 -*- # list comprehension and map import time def test(f, name): st = time.time() f() print '%s %ss' % (name, time.time() - st) TIMES = 1000 ARR = range ( 10000 ) def tmap(): i = 0 while (i<TIMES): map ( lambda x:x, ARR) i = i + 1 def tlst(): i = 0 while (i<TIMES): [x for x in ARR] i = i + 1 test(tmap, "map" ) test(tlst, "lst" ) |
在我电脑上的测试结果:
1
2
|
map 1.06299996376s lst 0.296000003815s |
很明显列表推导比map操作会快很多,都三倍速度了
希望本文所述对大家的Python程序设计有所帮助。