with in
: substring in string
:
>>> substring = "please help me out"
>>> string = "please help me out so that I could solve this"
>>> substring in string
True
def find_substring():
s = 'bobobnnnnbobmmmbosssbob'
cnt = 0
for i in range(len(s)):
if s[i:i+3] == 'bob':
cnt += 1
print 'bob found: ' + str(cnt)
return cnt
def main():
print(find_substring())
main()
Can also use this method
if substring in string:
print(string + '\n Yes located at:'.format(string.find(substring)))
Thought I would add this in case you are looking at how to do this for a technical interview where they don't want you to use Python's built-in function in
or find
, which is horrible, but does happen:
string = "Samantha"
word = "man"
def find_sub_string(word, string):
len_word = len(word) #returns 3
for i in range(len(string)-1):
if string[i: i + len_word] == word:
return True
else:
return False
People mentioned string.find()
, string.index()
, and string.indexOf()
in the comments, and I summarize them here (according to the Python Documentation):
First of all there is not a string.indexOf()
method. The link posted by Deviljho shows this is a JavaScript function.
Second the string.find()
and string.index()
actually return the index of a substring. The only difference is how they handle the substring not found situation: string.find()
returns -1
while string.index()
raises an ValueError
.
In [7]: substring = "please help me out"
In [8]: string = "please help me out so that I could solve this"
In [9]: substring in string
Out[9]: True
foo = "blahblahblah"
bar = "somethingblahblahblahmeep"
if foo in bar:
# do something
(By the way - try to not name a variable string
, since there's a Python standard library with the same name. You might confuse people if you do that in a large project, so avoiding collisions like that is a good habit to get into.)
You can also try find() method. It determines if string str occurs in string, or in a substring of string.
str1 = "please help me out so that I could solve this"
str2 = "please help me out"
if (str1.find(str2)>=0):
print("True")
else:
print ("False")
If you're looking for more than a True/False, you'd be best suited to use the re module, like:
import re
search="please help me out"
fullstring="please help me out so that I could solve this"
s = re.search(search,fullstring)
print(s.group())
s.group()
will return the string "please help me out".
Source: Stackoverflow.com