Finding the problem areas
When you are working with a small list, it might not seem like a lot of work to go through things manually and figure out what element has an issue. But if you have a list with hundreds or thousands of elements, you want to automate that process.
Now you'll look at a situation with a larger list, where you can see how the error message can be useful to check through the entire list for issues.
Deze oefening maakt deel uit van de cursus
Foundations of Functional Programming with purrr
Oefeninstructies
map()oversw_peopleand pull out the "height" element.map()oversafely()to convert the heights from centimeters into feet.- Set
quiet = FALSEso that errors are printed. - Pipe into
transpose(), to print the results first.
Praktische interactieve oefening
Probeer deze oefening eens door deze voorbeeldcode in te vullen.
# Map over sw_people and pull out the height element
height_ft <- map(___ , ___) %>%
map(safely(function(___){
___ * 0.0328084
}, quiet = ___)) %>%
___
# Print your list, the result element, and the error element
height_ft
height_ft[["result"]]
height_ft[["error"]]