获得介于m和n个字符之间的单词

Question

I am trying to get all names that start with a capital letter and ends with a full-stop on the same line where the number of characters are between 3 and 5

My text is as follows:

 King. Great happinesse

 Rosse. That now Sweno, the Norwayes King,
Craues composition:
Nor would we deigne him buriall of his men,
Till he disbursed, at Saint Colmes ynch,
Ten thousand Dollars, to our generall vse

 King. No more that Thane of Cawdor shall deceiue
Our Bosome interest: Goe pronounce his present death,
And with his former Title greet Macbeth

 Rosse. Ile see it done

 King. What he hath lost, Noble Macbeth hath wonne.

I am testing it out on this link . I am trying to get all words between 3 and 5 but haven't succeeded.

Answer 1

Does this produce your desired output?

import re

re.findall(r'[A-Z].{2,4}\.', text)

When text contains the text in your question it will produce this output:

['King.', 'Rosse.', 'King.', 'Rosse.', 'King.']

The regex pattern matches any sequence of characters following an initial capital letter. You can tighten that up if required, eg using [az] in the pattern [AZ][az]{2,4}\\. would match an upper case character followed by between 2 to 4 lowercase characters followed by a literal dot/period.

If you don't want duplicates you can use a set to get rid of them:

>>> set(re.findall(r'[A-Z].{2,4}\.', text))
set(['Rosse.', 'King.'])

Answer 2

You may have your own reasons for wanting to use regexs here, but Python provides a rich set of string methods and (IMO) it's easier to understand the code using these:

matched_words = []
for line in open('text.txt'):
    words = line.split()
    for word in words:
        if word[0].isupper() and word[-1] == '.' and 3 <= len(word)-1 <=5:
            matched_words.append(word)
print matched_words