如何將多個循環合併爲一個循環？

Question

這是我的代碼

word = ["General William Shelton, said the system", 
     "which will provide more precise positional data", 
     "and that newer technology will provide more", 
     "Commander of the Air Force Space Command", 
     "objects and would become the most accurate metadata"] 

matched_word = ["will", "and", "in", "the", "a", "A"] 

我曾嘗試這樣的代碼：

print word[0] 
for item in matched_word: 
     print item,":",word[0].count(item) 

print word[1] 
for item in matched_word: 
     print item,":",word[1].count(item) 

print word[2] 
for item in matched_word: 
     print item,":",word[2].count(item) 

print word[3] 
for item in matched_word: 
     print item,":",word[3].count(item) 

我得到我想要的輸出，但我不如何創建一個循環這一切的循環。 謝謝

輸出應該是這樣的：

General William Shelton, said the system 
will : 0 
and : 0 
in : 0 
the :1 
a : 3 
A : 0 
which will provide more precise positional data 
will : ! 
and : 0 
in : 0 
the : 0 
a : 3 
A : 0 

...等..

Answer 1

添加外循環：

for w in word: 
    print w 
    for item in matched_word: 
     print item, ":" ,w.count(item) 

Answer 2

另一種做法be

import itertools 
for w, item in itertools.product(word, matched_word): 
    print item, ":", w.count(item) 

itertools.product()給出了給定迭代的所有可能組合。

如果您需要新討論的print w，此解決方案無法正常工作。在這種情況下，這種解決方案是不合適的。

Answer 3

嘗試嵌套列表理解

counts = [(w, i, w.count(i)) for w in word for i in matched_word] 

你會採取這樣的

[('General William Shelton, said the system', 'will', 0), 
('General William Shelton, said the system', 'and', 0), 
('General William Shelton, said the system', 'in', 0), 
('General William Shelton, said the system', 'the', 1), 
('General William Shelton, said the system', 'a', 3), 
('General William Shelton, said the system', 'A', 0), 
('which will provide more precise positional data', 'will', 1), 
('which will provide more precise positional data', 'and', 0), 
('which will provide more precise positional data', 'in', 0), 
('which will provide more precise positional data', 'the', 0), 
('which will provide more precise positional data', 'a', 3), 
('which will provide more precise positional data', 'A', 0), 
('and that newer technology will provide more', 'will', 1), 
('and that newer technology will provide more', 'and', 1), 
('and that newer technology will provide more', 'in', 0), 
('and that newer technology will provide more', 'the', 0), 
('and that newer technology will provide more', 'a', 2), 
('and that newer technology will provide more', 'A', 0), 
('Commander of the Air Force Space Command', 'will', 0), 
('Commander of the Air Force Space Command', 'and', 2), 
('Commander of the Air Force Space Command', 'in', 0), 
('Commander of the Air Force Space Command', 'the', 1), 
('Commander of the Air Force Space Command', 'a', 3), 
('Commander of the Air Force Space Command', 'A', 1), 
('objects and would become the most accurate metadata', 'will', 0), 
('objects and would become the most accurate metadata', 'and', 1), 
('objects and would become the most accurate metadata', 'in', 0), 
('objects and would become the most accurate metadata', 'the', 1), 
('objects and would become the most accurate metadata', 'a', 6), 
('objects and would become the most accurate metadata', 'A', 0)] 

數組那麼你可以使用groupby從itertools

groupped = groupby(counts, lambda i: i[0]) 

最後

for category, items in groupped: 
    print category, '\n', "\n".join([":".join(map(str, j[1:])) for j in list(items)])