Example on a ggplot2 image
library(ggplot2)
#> Error in get(paste0(generic, ".", class), envir = get_method_env()) :
#> objeto 'type_sum.accel' no encontrado
# counts (or sums of weights)
g <- ggplot(mpg, aes(class))
# Number of cars in each class:
g + geom_bar()
A ggplot2 image