Math operations with variables

As part of a data wrangling process, there will be tasks involving mathematical operations with variables, where there will be a need to add, multiply, or even calculate the log of numbers, for example. Ergo, working with a data frame or a Tibble object is recommended, due to the facilities to perform those operations with variables.

The most common math operators in R are as follows:

Figure 5.5 – A table with the R language’s math operators

If we still use the data frame with names and grades, just created for the last exercise, let’s imagine that the professor offered one extra point for those who wrote a paper. Let’s suppose everyone delivered it; here is how we can add a new column with the extra point:

# Extra point
# Scenario: everyone delivered
df$new_grade = df$grade + 1

Figure 5.6 – One point added to all the students

If the professor wants to normalize...