Retrieving Multiple list elemets

how am I supposed to know to use positive or negative indexing?

in the fb_rating_data , insta_rating_data , and `pandora_rating_data’. Wouldn’t the same number be in the answer for the the name of the app, the rating count, and the user rating

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Using either positive or negative indexing retrieves the same value:

In our solution we’ve used both to show both techniques, but if you use one or the other consistently your answer will be marked as correct.

I hope this helps,

Thank you

Heres’ my other question, when you count the indexes on the graph from track name 3 lands on price and then 4 (or -1) lands on rating_count am I supposed to skip Price when counting the indexes for some reason?
Apple Store.csv dataquest|689x245](upload://4yHtAjQe7XYy7lKLbjUKV5pAe2e.png)

If you look at the exercise, you’ll see that the lists are defined in the initial code, and don’t use the AppleStore.csv data set.

Why did they write this?
Why did they use 2???
Pls explain in detail and simply

The fb_rating_data list was built by indexing 3 elements - the name, the number of the ratings, and the rating itself. By doing fb_rating_data[2], you’re indexing the 3rd element of the fb_rating_data list, which is where the rating is kept.

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So we don’t have to index the other elements that we used ? And can we choose to index any of the elements that we used ?

I received an error message “avg_rating is greater than what we expected.”
Can’t I use negative indexing instead of positive indexing?

sum = fb_rating_data[-1] + insta_rating_data[-1] + pandora_rating_data[-1]
avg_rating = sum / 3

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Hi @SweetLuvOfMine,

You can use negative indexing like this:

row_1 = ['Facebook', 0.0, 'USD', 2974676, 3.5]
row_2 = ['Instagram', 0.0, 'USD', 2161558, 4.5]
row_3 = ['Clash of Clans', 0.0, 'USD', 2130805, 4.5]
row_4 = ['Temple Run', 0.0, 'USD', 1724546, 4.5]
row_5 = ['Pandora - Music & Radio', 0.0, 'USD', 1126879, 4.0]

fb_rating_data = [row_1[0], row_1[3], row_1[-1]]
insta_rating_data = [row_2[0], row_2[3], row_2[4]]
pandora_rating_data = [row_5[0], row_5[3], row_5[4]]

avg_rating = (fb_rating_data[-1] + insta_rating_data[-1] + pandora_rating_data[-1]) / 3

In your case, either this is due to a platform issue or the values for these lists might be incorrect:

fb_rating_data = [row_1[0], row_1[3], row_1[-1]]
insta_rating_data = [row_2[0], row_2[3], row_2[4]]
pandora_rating_data = [row_5[0], row_5[3], row_5[4]]


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Thanks Sahil! You’re right. I was using row_3 (‘Clash of Clans’) instead of row_5 (‘Pandora - Music and Radio’).

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