The “facet_wrap” Function in R

• Package: ggplot2

• Purpose: To create a multi-panel display of plots based on a categorical variable, wrapping the panels into a grid.

• General Class: Plot Facet

• Required Argument(s):

• facets: A formula specifying the variables to be faceted, separated by a tilde (~).

• Notable Optional Arguments:

• ncol, nrow: Number of columns or rows in the grid of facets.

• scales: Should scales be fixed (“fixed”) or free (“free”) across facets?

• labeller: A function or character vector for custom labeling of facets.

• Example:

• # Example usage
  library(ggplot2)
  
  # Create a data frame
  my_data <- data.frame(
  Category = rep(c("A", "B", "C", "D"), each = 4),
  Value = rnorm(16)
  )
  
  # Create a ggplot object with faceted panels
  my_plot <- ggplot(data = my_data, aes(x = Category, y = Value)) +
  geom_boxplot() +
  facet_wrap(~Category, ncol = 2) +
  labs(title = "Faceted Boxplots by Category", x = "Category", y = "Value")
  
  # Print the faceted plot
  print(my_plot)

• In this example, the facet_wrap function from the ggplot2 package is used to create a multi-panel display of boxplots, with each panel representing a different category. The ncol argument controls the number of columns in the grid of facets. Additional optional arguments customize the facet layout.