从列表中删除元组会删除一些元组，但不会删除一个元组

Question

我一定错过了一些很明显的东西。你知道吗

我有一个元组列表，它们是（短语，数字）对。我想从我的非索引词列表中删除包含非索引词的短语的整个元组。你知道吗

stopwords = ['for', 'with', 'and', 'in', 'on', 'down']
tup_list = [('faucet', 5185), ('kitchen', 2719), ('faucets', 2628),
            ('kitchen faucet', 1511), ('shower', 1471), ('bathroom', 1131),
            ('handle', 1048), ('for', 1035), ('cheap', 960), ('bronze', 807),
            ('tub', 797), ('sale', 771), ('sink', 762), ('with', 696),
            ('single', 620), ('kitchen faucets', 615), ('stainless faucet', 613),
            ('pull', 603), ('and', 477), ('in', 447), ('single handle', 430),
            ('for sale', 406), ('bathroom faucet', 392), ('on', 369),
            ('down', 363), ('head', 359), ('pull down', 357), ('wall', 351),
            ('faucet with', 350)]

for p,n in tup_list:
    print('p', p, p.split(), any(phrase in stopwords for phrase in p.split()))

print(len(tup_list))
for p,n in tup_list:
    if any(phrase in stopwords for phrase in p.split()):
        tup_list.remove((p,n))
        print('Removing', p)
print(len(tup_list))

print([item for item in tup_list if item[0] == 'in'])

当我运行上述命令时，会得到以下打印结果：

p faucet ['faucet'] False
p kitchen ['kitchen'] False
p faucets ['faucets'] False
p kitchen faucet ['kitchen', 'faucet'] False
p shower ['shower'] False
p bathroom ['bathroom'] False
p handle ['handle'] False
p for ['for'] True
p cheap ['cheap'] False
p bronze ['bronze'] False
p tub ['tub'] False
p sale ['sale'] False
p sink ['sink'] False
p with ['with'] True
p single ['single'] False
p kitchen faucets ['kitchen', 'faucets'] False
p stainless faucet ['stainless', 'faucet'] False
p pull ['pull'] False
p and ['and'] True
p in ['in'] True
p single handle ['single', 'handle'] False
p for sale ['for', 'sale'] True
p bathroom faucet ['bathroom', 'faucet'] False
p on ['on'] True
p down ['down'] True
p head ['head'] False
p pull down ['pull', 'down'] True
p wall ['wall'] False
p faucet with ['faucet', 'with'] True
29
Removing for
Removing with
Removing and
Removing for sale
Removing on
Removing pull down
Removing faucet with
22
[('in', 447)]

我的问题是：为什么不删除包含('in', 447)的元组？打印输出显示p in ['in'] True意思是“in”在非索引词列表中，那么tup_list.remove((p,n))为什么不删除它呢？你知道吗

Answer 1

当您从列表中删除一个项目时，索引会发生变化。当您迭代更改的列表时，您将看到意外的结果。你知道吗

这里有一个解决方案。这不是最有效的，但可能适合你的需要。你知道吗

remove_indices = []

for i, (p, n) in enumerate(tup_list):
    if any(phrase in stopwords for phrase in p.split()):
        remove_indices.append(i)
        print('Removing', p)

tup_list = [i for j, i in enumerate(tup_list) if j not in remove_indices]