iOS Python equivalent of Swift's array.count method

[patent10021]

I'm looking for the Python equivalent of Swift's count method. array.count.

If the dataset has 9,000 data points I want to be able to find the average rating by dividing by the number of items (rows). Naturally I want to divide by items.count. How is this done in Python?

row_1 = ['Facebook', 0.0, 'USD', 2974676, 3.5]
row_2 = ['Instagram', 0.0, 'USD', 2161558, 4.5]
row_3 = ['WeChat', 0.0, 'USD', 2130805, 4.5]
row_4 = ['Line', 0.0, 'USD', 1724546, 4.5]
row_5 = ['WhatsApp', 0.0, 'USD', 1126879, 4.0]

app_data_set = [row_1, row_2, row_3, row_4, row_5]

rating_sum = 0
    for item in app_data_set:
    rating = item[-1]
    rating_sum += rating

items_count = item[-1].count() // python doesn't like this nor does it like count(item[-1])
average_rating = rating_sum / items_count
print(average_rating)

I know Python also has enumerate with a counter variable like idx. You can then use idx count value for other things like boolean tests.

    for idx, item in enumerate(app_data_set):

In Swift we can easily do what I'm trying to do just by using dot syntax and the count method but I cannot figure it out in Python.

 

[chown33]

Here's an article on Stack Overflow:
https://stackoverflow.com/questions/1712227/how-do-i-get-the-number-of-elements-in-a-list

It links to the Python reference docs at python.org for the len() function. It might be worthwhile to bookmark the URL for the root node of the docs, for the Python version you're using.

I found that article, and many others, by googling search terms: python array count

 

[patent10021]

Thanks chown33, Thant worked a treat. I previously used the len() function to get the row count of a dataset, but thought I could use count() for lists since it actually does do counting. Problem is, count() only counts occurrences.

For anyone else who's interested, here's how len() works for arrays/lists just like Swift's count method.

for item in app_data_set:
    rating = item[-1]
    rating_sum += rating

ratings_count = len(app_data_set)
average_rating = rating_sum / ratings_count
print(average_rating)