how to calculate frequency of word in list

[desul]

Dear, 

 how to  calculate the frequency of the word in the list  if the word is not in the list  just return  word equals to  zero

[wavic]

You can't, if something is not in the list.

[j.crater]

You can use count method of list, here is the documentation page:
https://docs.python.org/3.5/tutorial/dat...tures.html

About returning words equal to zero - a simple if statement that checks result of count method should do.
Give it a go and post the code if you will require further help.

[buran]

You can't, if something is not in the list.

Really?

from collections import Counter
words = ['alpha', 'bravo', 'charlie', 'bravo', 'charlie', 'bravo']
c = Counter(words)
print(c['bravo'])
print(c['echo'])
# another way
print(words.count('alpha'))
print(words.count('echo'))

Output:
3
0
1
0

[wavic]

He is getting sero. This post is related to https://python-forum.io/Thread-how-can-r...below-code 

Why do you slice the list like this: mystr[:1]. Why don't you search for the whole string "domain ontologies"?