Project1: ValueError: could not convert string to float: '3.0M'

Q&A DQ Courses
, ,
#1

Screen Link:
https://app.dataquest.io/m/350/guided-project%3A-profitable-app-profiles-for-the-app-store-and-google-play-markets/5/removing-duplicate-entries-part-two

reviews_max = {}


for row in android_dataset[1:]:
    name = row[0]
    n_reviews = float(row[3])
    
    if name in reviews_max and reviews_max[name] < n_reviews:
        reviews_max[name] = n_reviews
        
    elif name not in reviews_max:
        reviews_max[name] = n_reviews
        
print(len(reviews_max))

What I expected to happen: The data set should have 9,659 rows

What actually happened:

ValueError                                Traceback (most recent call last)
<ipython-input-3-17ea9549b95e> in <module>
      4 for row in android_dataset[1:]:
      5     name = row[0]
----> 6     n_reviews = float(row[3])
      7 
      8     if name in reviews_max and reviews_max[name] < n_reviews:

ValueError: could not convert string to float: '3.0M'

I suspect this error comes from using the del function in a previous cell. However, using the kernel tab, I restarted and run all. In the previous cell it correctly shows I am left with 10841 rows.

Any help is appreciated. Thanks!

#2

Hi fso00294

Welcome to the community!

You haven’t deleted the faulty data, that’s why you’re getting this error.
You’ll have to go through Screen 3 and remove the wrong data first.
After deletion you’ll have 10840 rows, then run your code from above. Then, ypu won’t get this error.

Hope this helps.

#3

Thank you very much for the help.

Actually, I found what my error was. In a previous cell I already use the following lines:

…
android_dataset = android_dataset[1:]
…

So, when in the current cell I used the following code lines:
…
for row in android_dataset[1:]:
…

It made me incorrectly select the row numbers in the current cell.

Thanks again!