Why does my for loop doesn't count correct number of values that are equal to 'Online&#039-CodePudding

I am trying to count the number of people who's status is Online. I hate created a dictionary and also have created a count variable to keep track of people who are online. Below is my code and the error log. In below code, I expect count to be 2.

class Solution(object):

    def getStatus(self, status):
        count = 0

        for k, v in status.items():
            # I even tried to used json.load(status) to parse but it doesn't help

            if status[k].key() == "Online":
                count  = 1
            else:
                pass
        return count


if __name__ == "__main__":
    statuses = {
        "Alice": "online",
        "Bob": "offline",
        "Eve": "online",
    }
    print(Solution().getStatus(statuses))

Below is my error log

  if status[k].key() == "Online":
AttributeError: 'str' object has no attribute 'key'

CodePudding user response：

you want to check the value , you have access to it using variable v

you can use

if v == "online":

instead of

  if status[k].key() == "Online":

why are you getting the error ?

status[k] is the string which is the value in the dict, so you can't call function key() on it. To verify this, just print status[k] in your loop to observe this.

CodePudding user response：

In your loop, k will Alice, Bob, etc and v will be "online" or "offline". There's no key() function to be called.

So for example:

if v == 'online':
    ....

That would work. Note that the evaluation is case-sensitive, and your example has mixed case, so that needs to be consistent.

Having said that, what you should use is operator.countOf, which is much simpler:

>>> statuses = {
...         "Alice": "online",
...         "Bob": "offline",
...         "Eve": "online",
... }
>>> from operator import countOf
>>> countOf(statuses.values(), 'online')
2
>>> countOf(statuses.values(), 'offline')
1