Exercise

Failing to simplify

For interactive use, sapply() is great. It guesses the output type so that it can simplify, and normally that is fine. However, sapply() is not a safe option to be used when writing functions. If sapply() cannot simplify your output, then it will default to returning a list just like lapply(). This can be dangerous and break custom functions if you wrote them expecting sapply() to return a simplified vector.

Let's look at an exercise using a list containing information about the stock market crash of 2008.

Instructions

100 XP

The list market_crash has been created for you.

  • Use sapply() to get the class() of each element in market_crash.


A new list, market_crash2 has been created. The difference is in the creation of the date!

  • Use lapply() to get the class() of each element in market_crash2.
  • Use sapply() to get the class() of each element in market_crash2.


date in market_crash2 has multiple classes. Why couldn't sapply() simplify this?