22.5: Passing Aggregate Data to Functions

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Even though the previous example involved passing atomic data to a function, you can totally pass aggregate data as well. Suppose we’d like to be able to easily compute the IQR (recall p. 150) of a univariate data set. Writing a function to do that is a snap:

Code \(\PageIndex{1}\) (Python):

def IQR(some_data):

return some_data.quantile(.75) - some_data.quantile(.25)

We can now call it on anything we like, like our examples from p. 150 and p. 159:

Code \(\PageIndex{2}\) (Python):

print("The IQR of the YouTube plays data is {}".format(IQR(num_plays)))

print("The IQR of the NCAA scoring data is {}".format(IQR(pts)))

| The IQR of the YouTube plays data is 412.

| The IQR of the NCAA scoring data is 15.

Again, we named the function’s own argument (some_data) something different than the variables it was called with (num_plays first, and then pts). This is a happy and healthy thing.