More iteration with for loops
Iteration isn't just for reading in files though; iteration can be used to perform other actions on objects. First, you will try iterating with a for loop.
You're going to change each element of a list into a numeric data type and then put it back into the same element in the same list.
For this exercise, you will iterate using a for loop that takes list_of_df
, which is a list of character vector, but the characters are actually numbers! You need to change the character vectors to numeric so that you can perform mathematical operations on them; you can use the base R function, as.numeric()
to do that.
This exercise is part of the course
Foundations of Functional Programming with purrr
Exercise instructions
- Check the class type of the first element of
list_of_df
. - Build a for loop that takes each element of
list_of_df
, changes it into numeric data withas.numeric()
, and adds it back into the same element oflist_of_df
. - Check the class type of the first element of
list_of_df
. - Print
list_of_df
.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Check the class type of the first element
class(___[[___]])
# Change each element from a character to a number
for(i in seq_along(list_of_df)){
___[[___]] <- as.numeric(___[[___]])
}
# Check the class type of the first element
class(___[[___]])
# Print out the list
___