Having a hard time remembering shorthand code for python/pandas methods and techniques

Q&A Non-DQ Courses
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#1

I’m currently doing the Intermediate Python and Pandas course, and doing the guided project. I’m on page 3 which required some pandas string methods. It’s towards the last couple tasks:

You likely found that the price and odometer columns are numeric values stored as text. For each column:

  • Remove any non-numeric characters.
  • Convert the column to a numeric dtype.

guided project page: https://app.dataquest.io/m/294/guided-project%3A-exploring-ebay-car-sales-data/3/initial-exploration-and-cleaning

I accomplished the task by doing it sort of ‘long-handed’:

autos["odometer"] = autos["odometer"].str.replace('km','') #works once while data type is a string
autos["odometer"] = autos["odometer"].str.replace(',','') #works once while data type is a string
autos["odometer"] = autos["odometer"].astype(int)

The solution, accomplished it short-hand:

autos["odometer"] = (autos["odometer"]
                         .str.replace("km","")
                         .str.replace(",","")
                         .astype(int)
                         )

solution link: https://nbviewer.jupyter.org/github/dataquestio/solutions/blob/master/Mission294Solutions.ipynb

I’m having a hard time remembering these short hand methods. Does it just come with time by looking at solutions and trying to remember the next time? Perhaps forcing myself to use it for some non-project tasks. Same goes for using shorthand when selecting rows and columns or method chaining. I tend to use intermediate steps. Might just gave to give it time and keep getting reminded but wondering if anyone has tips to speed up the process.

This might just be a rant, thank for listening if you made it this far!

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#2

Honestly I don’t think its necessary to remember the shorthands or syntactic sugar, because often they do not affect the time or space complexity of your code (and I think you will spend more time trying to remember the shorthand as compared with doing it the “longer” way). Rather, you should be looking at how to better optimise your code (e.g. using a list comprehension instead of a for-loop when it is possible), or reducing unnecessary code etc.

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#3

There are endless combinations of shorthands to memorize, so one way to handle that is to extract generally applicable principles that you can transfer to more future scenarios.

In this case what you see is method chaining syntax, where dot is used the chain endless methods.
Then you can think about why or when does this work?
What is it about the return type of the previous method that allows this method chaining?

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