filter 和ifilter这两个函数是内置模块itertools 提供的,通过两个例子来了解一下他们的作用
from itertools import *
lst = [3,6,1,4,8,6]
lst2 = filter(lambda x:x>3,lst)
print type(lst2)
print lst2
[6, 4, 8, 6]
from itertools import *
lst = [3,6,1,4,8,6]
lst2 = ifilter(lambda x:x>3,lst)
print type(lst2)
for i in lst2:
print i
6
4
8
6
from itertools import *
lst = [3,6,1,4,8,6]
lst2 = ifilter(lambda x:x>3,lst)
print type(lst2)
for i in lst2:
print i
for i in lst2:
print i