ggplot2:在每个方面重新排序从最高到最低的条形

时间:2017-04-03 04:35:10

标签: r ggplot2 geom-bar

在下面的df中,我想重新排列每个方面中从最高到最低 的条形

我试过

df <- df %>% tidyr::gather("var", "value", 2:4)
ggplot(df, aes (x = reorder(id, -value), y = value, fill = id))+
  geom_bar(stat="identity")+facet_wrap(~var, ncol =3)

它给了我 enter image description here

它没有在每个方面从最高到最低排序。

我想出了另一种获得我想要的方法。我不得不一次绘制每个变量,然后使用grid.arrange()

组合所有绘图
#I got this function from @eipi10's answer
#http://stackoverflow.com/questions/38637261/perfectly-align-several-plots/38640937#38640937  
#Function to extract legend
# https://github.com/hadley/ggplot2/wiki/Share-a-legend-between-two-ggplot2-graphs
g_legend<-function(a.gplot) {
  tmp <- ggplot_gtable(ggplot_build(a.gplot))
  leg <- which(sapply(tmp$grobs, function(x) x$name) == "guide-box")
  legend <- tmp$grobs[[leg]]
  return(legend)
}

p1 <- ggplot(df[df$var== "A", ], aes (x = reorder(id, -value), y = value, fill = id))+
  geom_bar(stat="identity") + facet_wrap(~var, ncol =3)

fin_legend <- g_legend(p1)
p1 <- p1 + guides(fill= F)

p2 <- ggplot(df[df$var== "B", ], aes (x = reorder(id, -value), y = value, fill = id))+
  geom_bar(stat="identity") + facet_wrap(~var, ncol =3)+guides(fill=FALSE) 

p3 <- ggplot(df[df$var== "C", ], aes (x = reorder(id, -value), y = value, fill = id))+
  geom_bar(stat="identity") + facet_wrap(~var, ncol =3)+guides(fill=FALSE) 


grid.arrange(p1, p2, p3, fin_legend, ncol =4, widths = c(1.5, 1.5, 1.5, 0.5))

结果就是我想要的 enter image description here

我想知道是否有一种简单的方法可以帮助我在所有方面从最高到最低的顺序排序,而不必分别绘制每个变量,然后将它们组合起来。任何建议将不胜感激。

数据

df <-  read.table(text = c("
id  A   B   C
site1   10  15  20
site2   20  10  30
site3   30  20  25
site4   40  35  40
site5   50  30  35"), header = T)

2 个答案:

答案 0 :(得分:5)

下面的方法使用专门为x轴设置facet_wrap()的变量,但使用labels参数scale_x_discrete()来显示正确的x轴标签:

准备数据

我在data.table更流利,所以这里使用了这个。随意使用您喜欢的数据包操作。

修改:删除了第二个虚拟变量,只需要ord

library(data.table)   
# reshape from wide to long
molten <- melt(setDT(df), id.vars = "id")
# create dummy var which reflects order when sorted alphabetically
molten[, ord := sprintf("%02i", frank(molten, variable, -value, ties.method = "first"))]

molten
#       id variable value ord
# 1: site1        A    10  05
# 2: site2        A    20  04
# 3: site3        A    30  03
# 4: site4        A    40  02
# 5: site5        A    50  01
# 6: site1        B    15  09
# 7: site2        B    10  10
# 8: site3        B    20  08
# 9: site4        B    35  06
#10: site5        B    30  07
#11: site1        C    20  15
#12: site2        C    30  13
#13: site3        C    25  14
#14: site4        C    40  11
#15: site5        C    35  12

创建情节

library(ggplot2)
# `ord` is plotted on x-axis instead of `id`
ggplot(molten, aes(x = ord, y = value, fill = id)) +
  # geom_col() is replacement for geom_bar(stat = "identity")
  geom_col() +
  # independent x-axis scale in each facet, 
  # drop absent factor levels (not the case here)
  facet_wrap(~ variable, scales = "free_x", drop = TRUE) +
  # use named character vector to replace x-axis labels
  scale_x_discrete(labels = molten[, setNames(as.character(id), ord)]) + 
  # replace x-axis title
  xlab("id")

enter image description here

数据

df <- read.table(text = "
id  A   B   C
site1   10  15  20
site2   20  10  30
site3   30  20  25
site4   40  35  40
site5   50  30  35", header = T)

答案 1 :(得分:1)

如果您愿意丢失X轴标签,可以使用实际y值作为x美学,然后在每个方面删除未使用的因子水平:

ggplot(df, aes (x = factor(-value), y = value, fill = id))+
    geom_bar(stat="identity", na.rm = TRUE)+
    facet_wrap(~var, ncol =3, scales = "free_x", drop = TRUE) +
    theme(
        axis.text.x = element_blank(),
        axis.ticks.x = element_blank()
    )

结果:

enter image description here

x轴标签的丢失在这里可能并不算太糟糕,因为你仍然有颜色可以继续(并且x轴因为它在整个面上不一致而仍然令人困惑)。