R 自动缩小以适合所有人？

有没有办法告诉ggplot2缩小以适应绘图的所有元素？例如，我想制作如下情节

我可以通过硬编码

coord_cartesian（xlim=c（-8,8.5））

来创建此图，但我想找到一种方法来自动确定这些值，以便代码可以在任何密度下工作

这是我现在的代码：

wrap_sentence <- function(string, width) {
  words <- unlist(strsplit(string, " "))
  fullsentence <- ""
  checklen <- ""
  for(i in 1:length(words)) {
    checklen <- paste(checklen, words[i])
    if(nchar(checklen)>(width+1)) {
      fullsentence <- paste0(fullsentence, "\n")
      checklen <- ""
    }
    fullsentence <- paste(fullsentence, words[i])
  }
  fullsentence <- sub("^\\s", "", fullsentence)
  fullsentence <- gsub("\n ", "\n", fullsentence)
  return(fullsentence)
}


library(ggplot2)
set.seed(02062017)
cutoff <- 0.75
t.text <- "There is a xx% chance that X improves achivement compared to Y"
c.text <- "There is a xx% chance that Y improves achivement compared to X"


df.plot <- data.frame(y = rnorm(n=100, mean = 0.5, sd = 2))

# Greater
ds <- density(df.plot$y, from = cutoff, to = max(df.plot$y))
ds_data <- data.frame(x = ds$x, y = ds$y)
prob_gt <- scales::percent(mean(df.plot[,"y"] > cutoff))

x_gt_end <- (max(df.plot[,"y"])+cutoff)/4
y_gt_end <- (density(df.plot[,"y"], from=x_gt_end, to=x_gt_end, n=1)$y)*2/3

x_gt_start <- (max(df.plot[,"y"])+cutoff)/2
y_start <-(density(df.plot[,"y"], from=x_gt_end, to=x_gt_end, n=1)$y + y_gt_end)/2

gt_y <- density(df.plot[,"y"], from=x_gt_start, to=x_gt_start, n=1)$y

gt_text <- gsub("xx%", prob_gt, t.text)

gt_text <- wrap_sentence(string = gt_text, width = 24)

# Less than

ds_less <- density(df.plot$y, from = min(df.plot$y), to = cutoff)
ds_data_less <- data.frame(x = ds_less$x, y = ds_less$y)
prob_lt <- scales::percent(1-mean(df.plot[,"y"] > cutoff))

x_lt_end <- (min(df.plot[,"y"])+cutoff)/4
y_lt_end <- (density(df.plot[,"y"], from=x_lt_end, to=x_lt_end, n=1)$y)*2/3

x_lt_start <- (min(df.plot[,"y"])+cutoff)/2
y_lt_start <-(density(df.plot[,"y"], from=x_lt_end, to=x_lt_end, n=1)$y + y_lt_end)/2

lt_text <- gsub("xx%", prob_lt, c.text)

lt_text <- wrap_sentence(string = lt_text, width = 24)

ggplot(df.plot, aes(y)) + geom_density() +
  geom_area(data = ds_data,
            aes(x = x, y = y),
            alpha = 0.5,
            fill = "darkblue") +
  geom_area(data = ds_data_less,
            aes(x = x, y = y),
            alpha = 0.5,
            fill = "darkred") +
  theme_bw() +
  geom_segment(aes(x = x_gt_start, y = y_start, xend = x_gt_end, yend = y_gt_end), 
               arrow = arrow(length=unit(0.30,"cm"), type = "closed"), 
               color="darkblue", alpha = 0.5, size=1) + 
  geom_label(aes(x = x_gt_start, y = y_start), label=gt_text, 
             vjust = "outward", hjust = "outward") + 
  geom_segment(aes(x = x_lt_start, y = y_lt_start, xend = x_lt_end, yend = y_lt_end), 
               arrow = arrow(length=unit(0.30,"cm"), type = "closed"), 
               color="darkred", alpha = 0.5, size=1) + 
  geom_label(aes(x = x_lt_start, y = y_lt_start), label=lt_text, 
             vjust = "outward", hjust = "outward") + 
  coord_cartesian(xlim = c(-8, 8.5))

---

wrap_语句不可能。Ggplot2不会将绘图面板设置为特定大小，而是允许其拉伸以填充设备。因此，无法防止文本对于绘图面板来说太大。但是，您可以根据您的数据和典型设备大小将扩展限制设置为一个好的猜测。我可以获取
geom\u标签
框的坐标并使用该坐标设置
coord\u笛卡尔坐标
？我基本上想象1。打印并保存在对象
p
，2中。检查对象p并从中提取坐标，3<代码>p+coord_笛卡尔坐标

使用（2）中的数据。