i dont know how to get the value of the number of times a word appears in a string...

Question

please help out
```wordcount.py
E.g. word_count("I do not like it Sam I Am") gets back a dictionary like:
{'i': 2, 'do': 1, 'it': 1, 'sam': 1, 'like': 1, 'not': 1, 'am': 1}
Lowercase the string to make it easier.
def word_count(words):
    dictionary = {}
    sentence = []
    for word in words:
        sentence.append(word)
    dictionary.update({word:
```

Alex Koumparos · Accepted Answer

Hi Nikhil,
First, think carefully about what Treehouse is giving you as an input to your function. You are calling it 'words' but you are being told that the thing you are getting is:
It should accept a single argument which will be a string. 
So this is really one long 'word' that you need to break into the constituent words. The typical string method you would use for this is 'split (https://docs.python.org/3/library/stdtypes.html#str.split)'.
It looks like you might think that your for word in words is doing the splitting for you, after all, the code is valid syntactically so it must be iterating over something, right? True, it is iterating over something but in this case it is individual characters (remember that strings behave like lists of characters) not words.
Next you are manually incrementing an index to get through your iterable. But remember that you don't manually iterate for in (you have to set the iterator in old C-style for loops, and while loops) but in a for in loop, Python will automatically work through each element in the iterable.
Next you are comparing sen to itself, which will always be True (if sen == sen). I'm not sure exactly what you are trying to do with this conditional. I think maybe you are trying to check if sen is in the dictionary. With your variable names, you could do this by writing:
Python
if sen in dictionary:

Which will check if sen is a key in dictionary.
Having established that sen is a key in dictionary we can use the basic syntax to update the value:
Python
dictionary[key] = dictionary[key] + 1  # we can make this shorter by using the `+=` operator

Remember that you also have to handle the case where sen isn't in dictionary (i.e., the first time sen appears in your loop). In that case you can update the dictionary using the same syntax but instead of giving it the the oldValue plus a difference, you just give it the initial value of 1.
Be careful with what types you are giving your dictionary. In your last line you are turning your number into a string, which you don't want to do.
Lastly, remember that your function needs to return something.
Cheers
Alex

Alex Koumparos · Answer

Hi Nikhil,
Instead of thinking in terms of counting the number of times a substring appears in a string, think about whether you can do each of the following:
1. split a string into words;
2. check if a key exists in a dictionary
3. add 1 to a value to a in a dictionary
If you can do the above, you can achieve the effect of counting the number of times a substring appears in a string.
Hope that gives you the necessary pointers
Cheers
Alex

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Nikhil Alexander

Nikhil Alexander

i dont know how to get the value of the number of times a word appears in a string...

2 Answers

Alex Koumparos

Alex Koumparos

Nikhil Alexander

Nikhil Alexander

Alex Koumparos

Alex Koumparos

Nikhil Alexander

Nikhil Alexander