bar z-index for ggplot2 geom_bar

Question

我创建了以下图形ggplot

使用以下代码;

p <- ggplot(df, aes(x=100*prop_select, y=(1500-s_meanResponse), fill=product)) + 
  geom_bar(stat='identity', width=2,  alpha=.6, color='#333333') + 
  coord_cartesian(xlim = c(0, 5)) +
  coord_flip()

print(p)

我试图故意重叠这些酒吧。我想知道如何更改每个条的z-index（深度）。我试图通过简单地重新排序确定我的条形的因子列的级别

来做到这一点

# Order by mean response to make sure that bars are layered correctly (does not work!)
# Switching this minus makes no difference to the bar z-index but does reverse legend entries
df <- df[sort.list(-df$s_meanResponse),] 
df$product <- factor(df$product, levels=df$product)

有人知道ggplot2是否可以这样做吗？

编辑：

数据框的结构类似于下面的

df <- data.frame( product=c('a','b','c'), s_meanResponse=c(1120,1421,1320), prop_select=c(.3,.2,.5))

Answer 1

我使用以下df实际重叠：

df <- data.frame(product=c('a','b','c'), 
                 s_meanResponse=c(1120,1421,1320), 
                 prop_select=c(.311,.32,.329))

无论因素水平排序如何，绘图顺序似乎都保持不变，而只是绘制从最低到最高y值的条形图。要实现自定义排序，我们必须执行以下操作，按所需顺序逐个绘制图层：

geom_bars_with_order <- function(vals)
{
  l <- list()
  for (i in vals) 
  {
    l <- c(l, geom_bar(data = df[df$product == i, ], 
                       stat='identity', width=2, alpha=.6, color='#333333'))  
  }
  l
}
# default order
ggplot(NULL, aes(x=100*prop_select, y=(1500-s_meanResponse), fill=product)) + 
  geom_bars_with_order(c("a", "b", "c")) +
  coord_cartesian(xlim = c(0, 5)) +
  coord_flip()

# custom order, "a" on top
ggplot(NULL, aes(x=100*prop_select, y=(1500-s_meanResponse), fill=product)) + 
  geom_bars_with_order(c("b", "c", "a")) +
  coord_cartesian(xlim = c(0, 5)) +
  coord_flip()