如何从txt文件中搜索单词到python

Question

How can I show words which length are 20 in a text file?

To show how to list all the word, I know I can use the following code:

#Program for searching words is in 20 words length in words.txt file
def main():
    file = open("words.txt","r")
    lines = file.readlines()
    file.close()
    for line in lines:
        print (line)
    return

main()

But I not sure how to focus and show all the words with 20 letters.

Big thanks

Answer 1

If your lines have lines of text and not just a single word per line, you would first have to split them, which returns a list of the words:

words = line.split(' ')

Then you can iterate over each word in this list and check whether its length is 20.

for word in words:
    if len(word) == 20:
        # Do what you want to do here

If each line has a single word, you can just operate on line directly and skip the for loop. You may need to strip the trailing end-of-line character though, word = line.strip('\\n') . If you just want to collect them all, you can do this:

words_longer_than_20 = []    
for word in words:
        if len(word) > 20:
            words_longer_than_20.append(word)

Answer 2

If your file has one word only per line, and you want only the words with 20 letters you can simply use:

     with open("words.txt", "r") as f:
         words = f.read().splitlines()
         found = [x for x in words if len(x) == 20]

you can then print the list or print each word seperately

Answer 3

You can try this:

f = open('file.txt')
new_file = f.read().splitlines()

words = [i for i in f if len(i) == 20]

f.close()