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Python Regular Expressions in Python Introduction to Regular Expressions Escapes

Posted by ahmedagour
ahmedagour
Courses Plus Student 216 Points

I have wrote a function that returns the first digit in a string I am not sure what is the problem in my code

Not sure what the questions is asking of me

escapes.py 
import re

def first_number(searchstring):
    matchobj = re.match(r'\d', searchstring)
    return matchobj

3 Answers

ahmedagour
PLUS
ahmedagour
Courses Plus Student 216 Points
ahmedagour
ahmedagour
Courses Plus Student 216 Points

but doesn't this r' to tell python it is a string ?

yk7
seal-mask
.a{fill-rule:evenodd;}techdegree
yk7
Full Stack JavaScript Techdegree Student 22,891 Points
yk7
.a{fill-rule:evenodd;}techdegree
yk7
Full Stack JavaScript Techdegree Student 22,891 Points

I tested your code in pycharm , and it's good, the string must start with digit and it returns a re.Match Class. 

import re

def first_number(searchstring) :
    ''' extracting digit from string '''
    a = re.match('\d', searchstring)
    print(type(a))
    print(a)

first_number("4Lives")

and it returns : 

<class 're.Match'>
<re.Match object; span=(0, 1), match='4'>

if you want to grab a digit from a string regardless where it positioned in the string, "live4ever" you need to use findall() instead of match().

you are right , r is for raw. and has no effect here. sorry about before!