ggplot2 自动调整数据点的 ylim。有什么方法可以调整 stat_summary 的 ylim 吗？

df <- structure(list(Varieties = structure(c(2L, 3L, 4L, 1L, 2L, 3L, 
4L, 1L, 2L, 3L, 4L, 1L, 2L, 3L, 4L, 1L, 2L, 3L, 4L, 1L, 2L, 3L, 
4L, 1L, 2L, 3L, 4L, 1L, 2L, 3L, 4L, 1L, 2L, 3L, 4L, 1L, 2L, 3L, 
4L, 1L, 2L, 3L, 4L, 1L, 2L, 3L, 4L, 1L, 2L, 3L, 4L, 1L, 2L, 3L, 
4L, 1L, 2L, 3L, 4L, 1L), .Label = c("F9917", "Hegari", "JS263", 
"JS2002"), class = "factor"), Priming = structure(c(2L, 2L, 2L, 
2L, 5L, 5L, 5L, 5L, 3L, 3L, 3L, 3L, 1L, 1L, 1L, 1L, 4L, 4L, 4L, 
4L, 2L, 2L, 2L, 2L, 5L, 5L, 5L, 5L, 3L, 3L, 3L, 3L, 1L, 1L, 1L, 
1L, 4L, 4L, 4L, 4L, 2L, 2L, 2L, 2L, 5L, 5L, 5L, 5L, 3L, 3L, 3L, 
3L, 1L, 1L, 1L, 1L, 4L, 4L, 4L, 4L), .Label = c("CaCl2", "Dry", 
"Hydropriming", "KNO3", "OnFarmpriming"), class = "factor"), 
    PH = c(225.8, 224.26, 228.9, 215.82, 230.3, 227.7, 232.8, 
    221.1, 260.2, 230.8, 236.75, 230.5, 250.56, 230.74, 240.64, 
    226.7, 268.4, 233.4, 243.33, 232.7, 252.04, 233.1, 237.14, 
    220.6, 265.55, 234.93, 240.04, 218.21, 300.55, 245, 243.5, 
    234.65, 253.3, 233.5, 238.62, 225.93, 255.74, 233.64, 238.1, 
    230.93, 246, 240.33, 246.08, 221.7, 250.54, 242.87, 251, 
    225.32, 251.47, 245.4, 266.74, 227.73, 290.62, 246.68, 256.4, 
    225.83, 282.67, 240.58, 258.35, 235.87)), .Names = c("Varieties", 
"Priming", "PH"), class = "data.frame", row.names = c(NA, 60L 
)) 
 
p1 <- ggplot(data=df, aes(x=Varieties, y=PH, group=Priming, shape=Priming, colour=Priming))+ 
     stat_summary(fun.y=mean, geom="point", size=2, aes(group=Priming, shape=Priming, colour=Priming))+ 
     theme_bw() 
p1 <- p1 + stat_summary(fun.y=mean, geom="line", aes(group=Priming, shape=Priming, colour=Priming)) 
print(p1) 

查看 ylim 中的额外空间以获得 stat_summary 值。预先感谢您的帮助和时间。

请您参考如下方法:

这是一种方法，使用 plyr 在绘图前准备数据

df <- ddply(df, .(Varieties, Priming), transform, meanPH = mean(PH)) 
ggplot(df, aes(Varieties, meanPH)) +  
  geom_point() + 
  geom_line(aes(group = Priming, color = Priming))