Why does this code keep printing out 0? Election Results

Get Help Python
#1

https://www.codecademy.com/courses/intro-statistics-numpy/projects/election-binomial
Whenever I try to write this code for number 3:

percentage_ceballos = total_ceballos/len(survey_responses)

It prints out 0 and I can’t understand why.
Then when I put 100 * in front of it:

percentage_ceballos =100 * total_ceballos/len(survey_responses)

It prints out 47, the desired answer.
Similarly, the answer is this:

percentage_ceballos = total_ceballos/float(len(survey_responses))

Why does that fix the problem as well?

#2

That sounds like Python2 to me where integer division performs floor division. As you noted making one of the values in your expression into a float sorted the issue. *Bounced this into get help-python.

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#3

The 100 * is there to convert the decimal (0.47) to a percentage (47%).

As for the division, that’s strange. As @tgrtim mentioned, it’s what would have happened in Python 2.

#4

Was this course made for Python 2? Because I really don’t get this. I learned Python 3. Also, I’m 99% sure that in Python 3, even if you don’t put the 100* it will give you 0.47.

#5

That particular project would appear to be using Python 2, yes:

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image1280×307 29.9 KB

That would seem to explain the floor division behaviour. :sweat:

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#6

Is there a particular reason why it’s using Python 2?

#7

It’s older content. The pro content is all python 3 I think.

#8

I think it’s just a bit inconsistent with versioning throughout and sometimes you’ll have to test which version is actually running, e.g. import sys; print(sys.version). If it really bothers you, you could always import the relevant bits: from __future__ import division and such though you’d need to copy it into each script so sometimes it’ll just be easier with float().

#9

Yep, this is an older project. It was part of the Data Analytics Intensive that I took in 2017.

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