#戒指图
dat=data.frame(count=c(10,60,30),category=c('A',"B","C"))
dat$fraction=dat$count/sum(dat$count)
dat=dat[order(dat$fraction),]
dat$ymax=cumsum(dat$fraction)
dat$ymin=c(0,head(dat$ymax,n=-1))
ggplot(dat,aes(fill=category,ymax=ymax,ymin=ymin,
xmax=5,xmin=3))+ #戒指粗细
geom_rect()+
coord_polar(theta = 'y')+
xlim(c(0,5))+ #此范围要包含(xmin,xmax)
theme(panel.grid = element_blank(),
axis.text = element_blank(),
axis.ticks = element_blank(),
axis.title = element_blank())+
annotate("text",x=0,y=0,label='Ring plot',
color='forestgreen',fontface='bold')+
annotate("text",x=c(4,4,4),y=c(0.05,0.25,0.7),
label=c('A','C','B'))+ #戒指环每部分添加文字
labs(title = '')+
theme(legend.position = 'none')