Finding missing observations
You're an inspector at a nuclear plant and have to validate whether every reactor has received its daily safety check over the course of a full year. The safety check logs are in reactor_df, a data frame with columns date, reactor, and check.
Two vectors, dates and reactors, with all dates of the year and reactors at the plant respectively have been created for you.
You'll use the combination of the expand_grid() and anti_join() functions to find dates where particular reactors were not checked.
The dplyr package has been pre-loaded for you.
Cet exercice fait partie du cours
Reshaping Data with tidyr
Instructions
- Use the
expand_grid()function to create a tibble holding all combinations of the variablesdateandreactor. Use thedatesandreactorsvectors created for you. - Perform an anti-join between
full_dfandreactor_dfon thedateandreactorcolumns.
Exercice interactif pratique
Essayez cet exercice en complétant cet exemple de code.
# Create a tibble with all combinations of dates and reactors
full_df <- ___
# Find the reactor - date combinations not present in reactor_df
full_df %>%
___