Data frames and matrices - column selection
All values in a matrix must have the same data type, which has efficiency implications when selecting rows and columns.
Suppose we have two objects, mat (a matrix) and df (a data frame).
This exercise is part of the course
Writing Efficient R Code
Exercise instructions
Using the microbenchmark() function, how long does it take to select the first column from each of these object? In other words, which is faster mat[, 1] or df[, 1]?
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Which is faster, mat[, 1] or df[, 1]?
microbenchmark(___, ___)