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Python Regular Expressions in Python Introduction to Regular Expressions Word Length

Posted by Kathryn Klarich
Kathryn Klarich
4,622 Points

How to include a variable in regular expression character matching?

Hello,

How do you incorporate a variable passed to the function into a regex expression? (see code attached) for example, if i want to look for 3+ characters i would type \w{3,}. however, if i want to be able to specify the '3' as a variable passed to a function, for example {count,} where count = 3, i get an empty list. Could someone explain how to make this work?

Thanks!

Kathryn

word_length.py 
import re

def find_words(count, string1):

    retrun re.findall(r'\w{count,}', string1)


find_words(3, 'boy, girl, to, from, by, bye')

2 Answers

Cheo R
Cheo R
37,150 Points
Cheo R
Cheo R
37,150 Points

You need to convert your count variable into a string. 

    a = "a"
    a + 1
    Traceback (most recent call last):
    File "python", line 1, in <module>
    TypeError: Can't convert 'int' object to str implicitly

    a = "a"
    a + str(1)
    'a1'
Kathryn Klarich
Kathryn Klarich
4,622 Points
Kathryn Klarich
Kathryn Klarich
4,622 Points

Thanks so much!