devtools::install_github("abikoushi/ggfloatbar")

library(ggfloatbar)
ggplot(sleep, aes(x=ID, y=extra, colour=group))+
  geom_float()

ggplot(sleep, aes(x=ID, y=extra, colour=group))+
  geom_floatbar(alpha=0.5)+
  geom_float()

ggplot(sleep, aes(x=ID, y=extra, colour=group, fill=group))+
  geom_floatbar(alpha=0.5)+
  geom_float()

ggplot(Orange,aes(x = age, y = circumference)) +
  geom_floatbar(aes(fill = Tree), alpha=0.8)+
  geom_line(aes(color = Tree))