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在python中读取文本文件并将其拆分为单个单词

[英]Reading a text file and splitting it into single words in python

我有这个由数字和单词组成的文本文件,例如这样 - 09807754 18 n 03 aristocrat 0 blue_blood 0 patrician我想拆分它,以便每个单词或数字都作为一个新行出现。

空格分隔符是理想的,因为我希望带破折号的单词保持连接。

这是我到目前为止:

f = open('words.txt', 'r')
for word in f:
    print(word)

不太确定如何从这里开始,我希望这是输出:

09807754
18
n
3
aristocrat
...

鉴于此文件:

$ cat words.txt
line1 word1 word2
line2 word3 word4
line3 word5 word6

如果您一次只想要一个单词(忽略文件中空格与换行符的含义):

with open('words.txt','r') as f:
    for line in f:
        for word in line.split():
           print(word)    

印刷:

line1
word1
word2
line2
...
word6 

同样,如果您想拼合文件到文件中的单词一个平面列表,你可以做这样的事情:

with open('words.txt') as f:
    flat_list=[word for line in f for word in line.split()]

>>> flat_list
['line1', 'word1', 'word2', 'line2', 'word3', 'word4', 'line3', 'word5', 'word6']

它可以使用print '\\n'.join(flat_list) ... 创建与第一个示例相同的输出。

或者,如果您想要文件每一行中单词的嵌套列表(例如,从文件创建行和列的矩阵):

with open('words.txt') as f:
    matrix=[line.split() for line in f]

>>> matrix
[['line1', 'word1', 'word2'], ['line2', 'word3', 'word4'], ['line3', 'word5', 'word6']]

如果您想要一个正则表达式解决方案,它将允许您在示例文件中过滤wordNlineN类型的单词:

import re
with open("words.txt") as f:
    for line in f:
        for word in re.findall(r'\bword\d+', line):
            # wordN by wordN with no lineN

或者,如果您希望它成为带有正则表达式的逐行生成器:

 with open("words.txt") as f:
     (word for line in f for word in re.findall(r'\w+', line))
f = open('words.txt')
for word in f.read().split():
    print(word)

作为补充,如果您正在读取一个非常大的文件,并且您不想一次将所有内容读入内存,您可以考虑使用buffer ,然后通过 yield 返回每个单词:

def read_words(inputfile):
    with open(inputfile, 'r') as f:
        while True:
            buf = f.read(10240)
            if not buf:
                break

            # make sure we end on a space (word boundary)
            while not str.isspace(buf[-1]):
                ch = f.read(1)
                if not ch:
                    break
                buf += ch

            words = buf.split()
            for word in words:
                yield word
        yield '' #handle the scene that the file is empty

if __name__ == "__main__":
    for word in read_words('./very_large_file.txt'):
        process(word)

你可以做的是使用 nltk 来标记单词,然后将所有单词存储在一个列表中,这就是我所做的。 如果你不知道 nltk; 它代表自然语言工具包,用于处理自然语言。 如果你想开始,这里有一些资源 [ http://www.nltk.org/book/]

import nltk 
from nltk.tokenize import word_tokenize 
file = open("abc.txt",newline='')
result = file.read()
words = word_tokenize(result)
for i in words:
       print(i)

输出将是这样的:

09807754
18
n
03
aristocrat
0
blue_blood
0
patrician
with open(filename) as file:
    words = file.read().split()

它是文件中所有单词的列表。

import re
with open(filename) as file:
    words = re.findall(r"([a-zA-Z\-]+)", file.read())

这是我完全实用的方法,它避免了阅读和拆分行。 它使用了itertools模块:

注意 python 3,用map替换itertools.imap

import itertools

def readwords(mfile):
    byte_stream = itertools.groupby(
        itertools.takewhile(lambda c: bool(c),
            itertools.imap(mfile.read,
                itertools.repeat(1))), str.isspace)

    return ("".join(group) for pred, group in byte_stream if not pred)

示例用法:

>>> import sys
>>> for w in readwords(sys.stdin):
...     print (w)
... 
I really love this new method of reading words in python
I
really
love
this
new
method
of
reading
words
in
python
           
It's soo very Functional!
It's
soo
very
Functional!
>>>

我想在你的情况下,这将是使用该功能的方式:

with open('words.txt', 'r') as f:
    for word in readwords(f):
        print(word)

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