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Python Introduction to Data Visualization with Matplotlib Chart Toppers Scatter Plot

Pete P
Pete P
7,613 Points
Posted by Pete P
Pete P
7,613 Points

Why .pop() the last entry in the list of irises?

I'm just curious as to why there was an empty list at the end of the irises list that we had to pop off. Is there always an empty list as the last entry after reading a csv file?

Thanks for the help!

2 Answers

Ken Alger
STAFF
Ken Alger
Treehouse Teacher
Ken Alger
Ken Alger
Treehouse Teacher

Pete -

Great question. There isn't always an extra entry, but in this particular instance, there was. Although this course wasn't about, nor did we go into, data cleansing, you will often find cases in which doing some minor cleansing is needed.

Hope it helps and post back with any other questions.

Happy coding,
Ken

Pete P
Pete P
7,613 Points
Pete P
Pete P
7,613 Points

Many thanks!

Stephen Hanlon
Stephen Hanlon
11,845 Points
Stephen Hanlon
Stephen Hanlon
11,845 Points

In this part of the code, if you print(irises) you'll see the empty list at the end.

with open(input_file, 'r') as iris_data:
    irises = list(csv.reader(iris_data)) 
print(irises)