Python 类型错误：“生成器”对象没有属性“__getitem__”
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TypeError: 'generator' object has no attribute '__getitem__'
提问by MAS
I have written a generating function that should return a dictionary. however when I try to print a field I get the following error
我写了一个应该返回字典的生成函数。但是，当我尝试打印字段时，出现以下错误
print row2['SearchDate']
TypeError: 'generator' object has no attribute '__getitem__'
This is my code
这是我的代码
from csv import DictReader
import pandas as pd
import numpy as np
def genSearch(SearchInfo):
for row2 in DictReader(open(SearchInfo)):
yield row2
train = 'minitrain.csv'
SearchInfo = 'SearchInfo.csv'
row2 = {'SearchID': -1}
for row1 in DictReader(open(train)):
if 'SearchID' in row1 and 'SearchID' in row2 and row1['SearchID'] == row2['SearchID']:
x = deepcopy( row1 )
#x['SearchDate'] = row2['percent']
x.update(row2)
print 'new'
print x
else:
#call your generator
row2 = genSearch(SearchInfo)
print row2['SearchDate']
采纳答案by hspandher
Generator returns an iterator, you explicitly needs to call next on it.
Generator 返回一个迭代器，你需要明确地调用 next 。
Your last line of code should be something like -
你的最后一行代码应该是这样的 -
rows_generator = genSearch(SearchInfo)
row2 = next(rows_generator, None)
print row2['SearchDate']
Ideally, we use iterators in a loop, which automatically does the same for us.
理想情况下，我们在循环中使用迭代器，它会自动为我们做同样的事情。
回答by Reza Saidafkan
Generators are necessarily iterators, not iterables. Iterables contain
__item__()and __getitem__()methods, whilst iterators contain next()/ __next__()method (python version 2.x/3.x).
生成器必然是迭代器，而不是迭代器。迭代器包含
__item__()和__getitem__()方法，而迭代器包含next()/__next__()方法（python 版本 2.x/3.x）。
