字符串指數分裂在Python

Question

我找Python的方式來分割句子譯成話，還可以對所有詞的索引信息存儲在一個句子例如現在

a = "This is a sentence" 
b = a.split() # ["This", "is", "a", "sentence"] 

，我也想存儲所有的話

c = a.splitWithIndices() #[(0,3), (5,6), (8,8), (10,17)] 

什麼是實現splitWithIndices（最好的方式）的索引信息，確實蟒蛇有我可以用任何方法庫。任何幫助我計算單詞索引的方法都會很棒。

Answer 1

我覺得它更自然返回相應拼接的開始和結束。例如（0,4）而不是（0,3）

>>> from itertools import groupby 
>>> def splitWithIndices(s, c=' '): 
... p = 0 
... for k, g in groupby(s, lambda x:x==c): 
... q = p + sum(1 for i in g) 
... if not k: 
... yield p, q # or p, q-1 if you are really sure you want that 
... p = q 
... 
>>> a = "This is a sentence" 
>>> list(splitWithIndices(a)) 
[(0, 4), (5, 7), (8, 9), (10, 18)] 

>>> a[0:4] 
'This' 
>>> a[5:7] 
'is' 
>>> a[8:9] 
'a' 
>>> a[10:18] 
'sentence' 

Answer 2

這裏有一個方法使用正則表達式：

>>> import re 
>>> a = "This is a sentence" 
>>> matches = [(m.group(0), (m.start(), m.end()-1)) for m in re.finditer(r'\S+', a)] 
>>> matches 
[('This', (0, 3)), ('is', (5, 6)), ('a', (8, 8)), ('sentence', (10, 17))] 
>>> b, c = zip(*matches) 
>>> b 
('This', 'is', 'a', 'sentence') 
>>> c 
((0, 3), (5, 6), (8, 8), (10, 17)) 

作爲一個班輪：

b, c = zip(*[(m.group(0), (m.start(), m.end()-1)) for m in re.finditer(r'\S+', a)]) 

如果你只是想索引：

c = [(m.start(), m.end()-1) for m in re.finditer(r'\S+', a)]