Help_for_ShStudent.R

iris_boxplots_no_outliers.R

# https://stackoverflow.com/questions/49880268/ggplot-how-to-remove-the-outliers-from-multiple-boxplots?noredirect=1#49880268
library(tidyverse)

data(iris)

iris_long <- gather(iris, "key", "val", -Species)
    
# with the outliers
ggplot(iris_long, aes(Species, val)) +
    geom_boxplot() +
    facet_wrap(~key, scales = "free")

# build our own without the outliers using the underlying function boxplot.stats()
new_iris <- group_by(iris_long, key, Species) %>%
    nest() %>%
    mutate(stats = map(data, ~ unlist(.) %>%
                           boxplot.stats(x = ., do.out = FALSE) %>%
                           .$stats %>%
                           bind_rows %>%
                           set_names(c("ymin", "lower", "middle", "upper", "ymax"))))

stats <- unnest(new_iris, stats)

# that's better :)
ggplot(stats) +
    geom_boxplot(aes(x = Species, middle = middle, lower = lower, upper = upper, ymin = ymin, ymax = ymax),
                 stat = "identity") +
    facet_wrap(~key, scales = "free")