柱状图

library(ggplot2)

ggplot(iris, aes(x = Species, y = Sepal.Length)) + 
  stat_summary(fun.data = "mean_se", geom = "bar")

ggplot(iris, aes(x = Species, y = Sepal.Length, fill = Species)) + 
  stat_summary(fun.data = "mean_se", geom = "bar", width = 0.3) + 
  scale_fill_manual(values = c("steelblue", "orange", "firebrick")) + 
  theme_bw()