使用tidyverse的forcats和ggplot2软件包进行绘图的重新排序因子

Question

首先，感谢tidyverse ^{^ 13} 。 我希望下表中的柱线遵循由forcats::fct_reorder ()重新排序的相同因子水平。 令人惊讶的是，当View ()时，在数据集中看到的级别顺序与在图表中显示时的级别不同（请参见下文）。 该图表应说明在奖励分数之前和之后失败的学生人数（我想根据奖励之前的失败学生人数对条形进行排序）。

微机

  ggplot (df) +
  geom_bar (aes (forcats::fct_reorder (subject, FailNo, .desc= TRUE), FailNo, fill = forcats::fct_rev (Bonus)), position = 'dodge', stat = 'identity') +
  theme (axis.text.x=element_text(angle=45, vjust=1.5, hjust=1.5, size = rel (1.2)))

dput（df）的数据输出

structure(list(subject = structure(c(1L, 2L, 5L, 6L, 3L, 7L,
4L, 9L, 10L, 8L, 12L, 11L, 1L, 2L, 5L, 6L, 3L, 7L, 4L, 9L, 10L,
8L, 12L, 11L), .Label = c("CAB_1", "DEM_1", "SSR_2", "RRG_1",
"TTP_1", "TTP_2", "IMM_1", "RRG_2", "DEM_2", "VRR_2", "PRS_2",
"COM_2", "MEB_2", "PHH_1", "PHH_2"), class = "factor"), Bonus = structure(c(2L,
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L), .Label = c("After", "Before"), class = "factor"),
    FailNo = c(29, 28, 20, 18, 15, 13, 12, 8, 5, 4, 4, 2, 21,
    16, 16, 14, 7, 10, 10, 5, 3, 4, 4, 1)), .Names = c("subject",
"Bonus", "FailNo"), class = c("tbl_df", "tbl", "data.frame"), row.names = c(NA,
-24L))

条形图

问题

根据上表， SSR_2 var应该排在第五位， IMM_1应该IMM_1在第六位，但是在图表中我们看到这两个变量交换了位置。 在这种情况下，如何在tidyverse之后对其进行排序？

Answer 1

x轴具有unique级别的使用factor 。

ggplot (df) + 
 geom_bar (aes(factor(forcats::fct_reorder
 (subject, FailNo, .desc= TRUE), 
 levels=unique(subject)), 
 FailNo, 
 fill = forcats::fct_rev (Bonus)), 
 position = 'dodge', stat = 'identity') + 
 theme(axis.text.x=element_text(angle=45, vjust=1.5, hjust=1.5, size = rel (1.2)))

编辑：@ dotorate评论

Answer 2

奖金前排序不成功

library(dplyr)
df_before_bonus <- df %>% filter(Bonus == "Before") %>% arrange(desc(FailNo))

在奖金前使用FailNo来创建因子

df$subject <- factor(df$subject, levels = df_before_bonus$subject, ordered = TRUE)

更新剧情

ggplot(df) +
    geom_bar(aes (x = subject, y = FailNo, fill = as.factor(Bonus)), 
             position = 'dodge', stat = 'identity') +
    theme (axis.text.x=element_text(angle=45, vjust=1.5, hjust=1.5, size = rel (1.2)))