r - ggplot2:显示x轴标签的类别和子类别

Question

big_theme <- theme(
  panel.background = element_rect(fill = "black"),
  plot.background = element_rect(fill = "black", colour = NA),
  plot.title = element_text(hjust = 0.5, size = 15, color = "white"),
  axis.text.y = element_text(colour = "white", size = 14),
  axis.title.x = element_text(colour = "white", size = 14),
  axis.title.y = element_text(colour = "white", size = 14),
  axis.text.x = element_text(vjust = 1, angle = 45, color = "white", size = 14, hjust=1),
  strip.background = element_rect(fill = "black"),
  strip.text = element_text(colour = 'white'),
  strip.text.y = element_text(angle = 0), 
  legend.position = "top"
)

theme2 = theme(panel.background = element_rect(fill = 'black'),
  legend.background=element_rect(fill = "black"),
  legend.text = element_text(colour = "white", size = 14), 
  legend.justification = "right",
  legend.key.height = unit(1, "line"),
  legend.key = element_rect(color = "black", fill = "black"))

theme3 = theme(plot.background = element_rect(fill = 'black'))

plot1 <- ggplot(sample_data) + big_theme + theme2 + theme3
plot1 + 
  geom_col(position = "identity", 
           aes(x = category, y = value,
               fill = forcats::fct_relevel(variable, c("z", "x", "y")),
               color = forcats::fct_relevel(variable, c("z", "x", "y")))) + 
  scale_fill_manual(values = c("#000000","#D3667C","#53AC79")) + 
  scale_color_manual(values = c("#00A2EF","#D3667C","#53AC79")) + 
  geom_text(aes(label = big_category, x = big_category, y = 0), vjust = 0, 
            size = 3, color = "white", position = position_dodge(width = 1)) +  
  scale_y_continuous(limits = c(0, 2.4), expand = c(0, 0)) 

我有一个数据集，看起来像:

big_category category   variable    value
a     aa    x   1.2
a     ba    x   1.05
a     ca    x   1.11
a     aa    y   1.43
a     ba    y   1.09
a     ca    y   0.97
a     aa    z   1.12
a     ba    z   1.46
a     ca    z   1.32

b     ab    x   1.2
b     bb    x   1.05
b     cb    x   1.11
b     ab    y   1.43
b     bb    y   1.09
b     cb    y   0.97
b     ab    z   1.12
b     bb    z   1.46
b     cb    z   1.32
c     ac    x   1.2
c     ac    y   1.05
c     ac    z   1.11

我希望x轴按类别标记，而在下面我希望big_category标记。例如，我想要aa，ba和ca的轴标签，然后在ggplot中的big_category a下方的标签。我不希望它与类别标签混在一起，我也希望它在水平显示的x轴标签下面。

我也尝试过facet_grid，但这给我带来了一个问题，因为条的尺寸不均匀。像big_category a具有3个类别，而big_category c仅具有1个类别。我希望所有它们都具有相同的宽度，并且我想要一个连续的图。

更新资料

big_category category variable value
a aa111111111 x 1.2
a ba111111111 x 1.05
a ca111111111 x 1.11
a aa111111111 y 1.43
a ba111111111 y 1.09
a ca111111111 y 0.97
a aa111111111 z 1.12
a ba111111111 z 1.46
a ca111111111 z 1.32
b ab111111111 x 1.2
b ab111111111 y 1.05
b ab111111111 z 1.11
c ac111111111 x 1.2
c bc111111111 x 1.05
c cc111111111 x 1.11
c ac111111111 y 1.43
c bc111111111 y 1.09
c cc111111111 y 0.97
c ac111111111 z 1.12
c bc111111111 z 1.46
c cc111111111 z 1.32

码:

big_theme <- theme(
panel.background = element_rect(fill = "black"),
plot.background = element_rect(fill = "black", colour = NA),
plot.title = element_text(hjust = 0.5, size = 15, color = "white"),
axis.text.y = element_text(colour = "white", size = 14),
axis.title.x = element_text(colour = "white", size = 14),
axis.title.y = element_text(colour = "white", size = 14),
axis.text.x = element_text(vjust = 1, angle = 45, color = "white", size = 14, hjust=1),
strip.background = element_rect(fill = "black"),
strip.text = element_text(colour = 'white'),
strip.text.y = element_text(angle = 0),
legend.position = "top"
)

theme2 = theme(panel.background = element_rect(fill = 'black'),
legend.background=element_rect(fill = "black"),
legend.text = element_text(colour = "white", size = 14),
legend.justification = "right",
legend.key.height = unit(1, "line"),
legend.key = element_rect(color = "black", fill = "black"))

theme3 = theme(plot.background = element_rect(fill = 'black'))

ggplot(sample_data %>% mutate(variable=fct_relevel(variable, c("z","x","y")))) +
geom_col(position = "identity",
aes(x = category, y = value, fill = variable, color = variable)) +
facet_grid(. ~ big_category, space="free_x", scales="free_x", switch="x") +
big_theme + theme2 + theme3 +
theme(strip.placement = "outside",
strip.background = element_rect(fill=NA,colour="white"),
panel.spacing.x=unit(0,"cm"),
strip.text = element_text(hjust=0, face="bold", size=12))

Answer 1

下面是一个使用示例数据的示例，说明如何在category中包含big_category。为了简单起见，我仅包含必要的绘图元素。当然，您可以将特定的主题，颜色和其他元素添加到下面的基本图中。

library(tidyverse)

ggplot(sample_data %>% mutate(variable=fct_relevel(variable, c("z","x","y")))) +
  geom_col(position = "identity", 
           aes(x = category, y = value, fill = variable, color = variable)) + 
  facet_grid(. ~ big_category, space="free_x", scales="free_x", switch="x") +
  theme_classic() +
  theme(strip.placement = "outside",
        strip.background = element_rect(fill=NA, colour="grey50"),
        panel.spacing.x=unit(0,"cm"))

更新:如果我理解您的评论，请使用以下更新的代码对带状文本进行左对齐并删除带状边框。我不知道在 strip 之间只有垂直线的方法(无需在ggplot之外破解底层图形对象)。但是，我在面板之间添加了一些空间，并添加了面板边框来描绘 big_category级别。

ggplot(sample_data %>% mutate(variable=fct_relevel(variable, c("z","x","y")))) +
  geom_col(position = "identity", 
           aes(x = category, y = value, fill = variable, color = variable)) + 
  facet_grid(. ~ big_category, space="free_x", scales="free_x", switch="x") +
  theme_bw() +
  theme(strip.placement = "outside",
        strip.background = element_rect(fill=NA,colour=NA),
        panel.spacing.x=unit(0.15,"cm"), 
        strip.text = element_text(hjust=0, face="bold", size=12))

更新2:我创建了一个图，但作了以下更改:(1)x轴标签左端的 big_category标签，以及(2) big_category的唯一级别少于3个时，空白 category标签。为了用空白标签保持相同的方面“中断”，我们为每个以前的 big_category值创建了一个唯一的空格字符串(通过改变字符串的长度)。

我认为该图看起来不是很好(实际上，我认为在标准位置顶部的 big_category小平面条以及文本居中的情况下，效果会更好)，但是也许您可以尝试一下并获得满足您要求的内容需要。我已经注释了代码以解释其功能，但是如果有任何不清楚的地方请通知我。

我们将使用您发布的新 sample_data，但将第四级添加到 big_category:

sample_data = sample_data %>% 
  bind_rows(data_frame(big_category="d",
                       category=c("da1111111111", "db111111"),
                       variable=c("z","x"), value=c(1.1,0.6)))

现在，我们将对 sample_data进行一些转换，以对其进行设置以进行绘图并将调整后的数据帧直接传输到ggplot中:

sample_data %>% 
  mutate(variable=fct_relevel(variable, c("z","x","y"))) %>% 
  # Create grouping column (called short_cat) to mark levels of big_category 
  #  with two or fewer unique levels of category
  group_by(big_category) %>% 
  mutate(short_cat = length(unique(category)) <= 2) %>% 
  ungroup %>% 
  # Create a unique white-space string for each unique value of grp
  mutate(grp = c(0, cumsum(diff(short_cat) != 0)),
         grp = sapply(grp, function(g) paste(rep(" ", g), collapse="")),
         # Assign white-space strings to each level of big_category for which short_cat 
         # is TRUE
         big_category=replace(big_category, short_cat, grp[short_cat]),
         # Set factor order for big_category so new levels will stay in same order 
         #  as original levels
         big_category=factor(big_category, levels=unique(big_category))) %>%
  ggplot() +
    geom_col(position = "identity", width=0.8, 
             aes(x = category, y = value, fill = variable, color = variable)) + 
    facet_grid(. ~ big_category, space="free_x", scales="free_x", switch="x") +
    theme_bw() +
    theme(axis.text.x=element_text(angle=45, vjust=1, hjust=1),
          strip.placement = "outside",
          strip.background = element_rect(fill=NA,colour=NA),
          panel.spacing.x=unit(0.15,"cm"), 
          # Left justify big_category labels
          strip.text = element_text(hjust=0, face="bold", size=12)) +
    # Expand left side of x-axis so that big_category labels will be under left 
    #  end of x-axis labels
    expand_limits(x=-0.5)