我要说的是:
listOfStuff =([a,b], [c,d], [e,f], [f,g])
我想做的是,以类似于以下法典的方式通过中间2部分:
for item in listOfStuff(range(2,3))
print item
最终结果如下:
[c,d]
[e,f]
这项法典目前并不奏效,但我希望你能够理解我正在做些什么。
我要说的是:
listOfStuff =([a,b], [c,d], [e,f], [f,g])
我想做的是,以类似于以下法典的方式通过中间2部分:
for item in listOfStuff(range(2,3))
print item
最终结果如下:
[c,d]
[e,f]
这项法典目前并不奏效,但我希望你能够理解我正在做些什么。
listOfStuff =([a,b], [c,d], [e,f], [f,g])
for item in listOfStuff[1:3]:
print item
你们必须听从你们的传说。 <代码>1是你需要的第一个要素,3
(实际上为2+1)是你不需要的第一个要素。
清单中的要素从0项计算:
listOfStuff =([a,b], [c,d], [e,f], [f,g])
0 1 2 3
<代码>[1:3]包括要素1和2。
更高效的存储方式是使用islice()
,从itertools
上删除。 模块:
from itertools import islice
listOfStuff = ([ a , b ], [ c , d ], [ e , f ], [ g , h ])
for item in islice(listOfStuff, 1, 3):
print(item)
# [ c , d ]
# [ e , f ]
However, this can be relatively inefficient in terms of performance if the start value of the range is a large value since islice
would have to iterate over the first start value-1 items before returning items.
You want to use slicing.
for item in listOfStuff[1:3]:
print item
采用<代码>ter 建设:
l = [1, 2, 3]
# i is the first item.
i = iter(l)
next(i)
for d in i:
print(d)
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