ggplot2-geom_convexhull()函数绘制点集凸

1.Prepare data

library(ggplot2);library(dplyr)
dat <- rbind(data.frame(x = rnorm(50,1,sd = .8),y = rnorm(50,1,sd = .5),groups = "a"),
             data.frame(x = rnorm(60,3,sd = .5),y = rnorm(60,5,sd = .3),groups = "b"),
             data.frame(x = rnorm(90,4,sd = 1.),y = rnorm(90,1,sd = .6),groups = "c"))
-------------------------------------------------------
              x           y group
1   -0.91868184  0.67446740     a
2    0.28066967  0.97873870     a
52   3.22960282  4.75726027     b
53   2.49711939  5.78070916     b
54   2.99912717  5.33394315     b
141  3.64351920  1.56362945     c
142  4.67163828  0.86267089     c
...

2.Draw HULL

ggplot(dat , aes(x = x,y = y)) + geom_point(aes(color = groups),show.legend = F) + 
    geom_label(data = dat %>% group_by(groups) %>% summarise(x= mean(x),y = mean(y)),
               aes(x = x,y = y,label = groups,fill = groups),
               fontface = "bold",colour = "white",size = 8,show.legend = F) +
    coord_equal(xlim = c(-1,6),ylim = c(-1,6)) +
    ggConvexHull::geom_convexhull(aes(color = groups),fill = NA,show.legend = F) +
    theme_bw() + theme(panel.grid = element_blank())
-------------------------------------------------------