在 ggplot 输出上使用 coord_flip() 后添加大括号

Question

我正在尝试在 ggplot 输出的底部水平添加一个下括号，其 x-y 已被翻转（使用 coordin_flip()）。我将使用 mtcars 示例数据进行说明。

library(ggpubr)

data("mtcars")
dfm <- mtcars
# Convert the cyl variable to a factor
dfm$cyl <- as.factor(dfm$cyl)
# Add the name colums
dfm$name <- rownames(dfm)
# Subset the data
head(dfm[, c("name", "wt", "mpg", "cyl")])

# Sort by group and by ascending order

g <- ggbarplot(dfm, x = "name", y = "mpg",
          fill = "cyl",       # change fill color by cyl
         color = "white", # Set bar border colors to white
          palette = "jco",  # jco journal color palett. 
          sort.val = "asc",  # Sort the value in dscending order 
          sort.by.groups = TRUE, # Sort inside each group
          x.text.angle = 90 # Rotate vertically x axis texts
          ) + labs(title="Brand & MPG", y = " ", x = " Brand") + coord_flip()

然后我想在 ggplot 对象的底部添加一个水平花括号，使原始图看起来像这样。

所以我引用了 this post 并调用了 ggbrace 包，通过添加以下行修改代码：

g + geom_brace(aes(x=c(0,-3), y=c(0,35), label = "something"), inherit.data=F, rotate=90, labelsize=5) + coord_cartesian(y=range(dfm$mpg), clip = "off")

# coord_cartesian() is used in order to put the underbrace outside of the plotting area (at the bottom).

但是，Rreturns一个错误信息：

Coordinate system already present. Adding new coordinate system, which will replace the existing one.

关于如何调整 geom_brace() 函数内的参数以通过最少的修改获得所需结果的任何建议？

Answer 1

报错好像是不能同时使用coord_flip和coord_cartesian，所以首先要把coord_cartesian参数全部输入coord_flip.

然后，由于 x 是分类的，因此必须进行一些修改，以便 geom_brace 和 coord_flip 以相同的方式理解输入。

最后，你必须旋转 270 度而不是 90 度。

结果是：

ggbarplot(dfm, x = "name", y = "mpg",
               fill = "cyl",       # change fill color by cyl
               color = "white", # Set bar border colors to white
               palette = "jco",  # jco journal color palett. 
               sort.val = "asc",  # Sort the value in dscending order 
               sort.by.groups = TRUE, # Sort inside each group
               x.text.angle = 90 # Rotate vertically x axis texts
) + labs(title="Brand & MPG", y = " ", x = " Brand") + 
  geom_brace(aes(x=c(-1,0), y = c(0,35), label = "something"), inherit.data=F, rotate=270, labelsize=5) +
  coord_flip(clip="off", expand = FALSE,x=range(seq_along(dfm$name))) +
  theme(plot.margin = unit(c(0., 0., 0.5, 0.), units="lines"))

在 ggplot 输出上使用 coord_flip() 后添加大括号

Adding underbrace after using coord_flip() on ggplot output

r

ggplot2

curly-braces

ggpubr