Count function solution

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,
#1

Screen Link:
https://app.dataquest.io/m/1018/lists/9/counting-occurrences

My Code: 

def count(list1,obj):
    for val in list1[val]:
        if list1[val]=obj: 
            val+=1
    return val

What I expected to happen:

What actually happened:

  File "<ipython-input-1-5b7fc889f5dd>", line 3
    if list1[val]=obj:
                 ^
SyntaxError: invalid syntax

Why is this answer incorrect, please.

#2

missed adding ‘return val’ statement inside function
same error is returned though

#3

Hi @piya,

The error that you are getting is because you are comparing list1[val] and obj using =. The single equality sign is used to assign a value to a variable.

To compare two variables, you need to use a double equality sign: ==.

In your case, it would be:

def count(list1,obj):
    for val in list1[val]:
        if list1[val]==obj: 
            val+=1
    return val

Best,
François

2 Likes
#4

Thanks so much Francois. I’m finding this community so helpful.

I re-wrote the function this way:It works but I’m intrigued that i is printed 0,1,2,3,4 then again 3.
Why would i go back 1 in the end please?

def count(list1,obj):
    val=0
    for i in range(len(list1)):       
        if list1[i]==obj: 
            val+=1            
            print(i)
        else:
            print(str(i) +'else')           
    return val

count(['a','b','c','a','a'],'a')
#5

It does not go back 1. The 3 that you see is the result of count(['a','b','c','a','a'],'a'). In a Python script, if the last line results in a value that is not stored anywhere, this value gets printed.

If you replace the last line by result = count(['a','b','c','a','a'],'a') then the 3 will be stored in result instead of being printed.

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