如何减少R中分段图的空白?

似乎至少有两种不同的方法可以实现这一点:

scale_y_discrete ,正如@WaltS在评论中建议的那样:

ggplot(df, aes(color = step))+
    geom_segment(aes(x=start, xend=end, y=person, yend=person), 
                 size = 3)+
    xlab("duration")+
    scale_y_discrete(expand = expand_scale(mult = 0.1))

另一个使用 coord_cartesian

ggplot(df, aes(color = step))+
  geom_segment(aes(x=start, xend=end, y=person, yend=person), 
               size = 3)+
  xlab("duration")+
  coord_cartesian(expand = FALSE, #use no expansion
                  ylim = c(0.8,2.2), #set manually the limits in y
                  xlim = c(-1,12))  # set manually limits in x (or expand = F will make it tight!)