r - 条形图条走向错误的方向

Question

我是一名正在学习 R 的生物学研究生。我希望有人可以帮助我让条形图在相反的方向水平移动(蓝色部分应该从 0 开始，红色部分应该从 100 开始)。

带有错误方向的条形图

这是数据

my_species <- c('apomict_2-17-17_compreh', 'apomict_2-17-17_compreh', 'apomict_2-17-17_compreh', 'apomict_2-17-17_compreh', 'parthenogen_2-17-17_compreh', 'parthenogen_2-17-17_compreh', 'parthenogen_2-17-17_compreh', 'parthenogen_2-17-17_compreh', 'sexual_2-9-17', 'sexual_2-9-17', 'sexual_2-9-17', 'sexual_2-9-17')
my_species <- factor(my_species)
my_species <- factor(my_species,levels(my_species)[c(length(levels(my_species)):1)]) # reorder your species here just by changing the values in the vector :
my_percentage <- c(36.3, 56.3, 2.6, 4.8, 42.2, 50.6, 2.4, 4.8, 56.0, 19.9, 6.7, 17.4)
my_values <- c(522, 811, 38, 69, 608, 729, 35, 68, 806, 286, 96, 252)
category <- c(rep(c("S","D","F","M"),c(1)))
category <-factor(category)
category = factor(category,levels(category)[c(4,1,2,3)])
df = data.frame(my_species,my_percentage,my_values,category)

代码如下:

# Load the required libraries
library(ggplot2)
library("grid")

# !!! CONFIGURE YOUR PLOT HERE !!! 
# Output
#my_output <- paste("/home/loki/","busco_figure.png",sep="/") 
my_width <- 20
my_height <- 15
my_unit <- "cm"

# Colors
my_colors <- c("#56B4E9", "#3492C7", "#F0E442", "#F04442")
# Bar height ratio
my_bar_height <- 0.75

# Legend
my_title <- "BUSCO Assessment Results"

# Font
my_family <- "sans"
my_size_ratio <- 1


# Code to produce the graph
labsize = 1
if (length(levels(my_species)) > 10){
 labsize = 0.66
}
print("Plotting the figure ...")


figure <- ggplot() +       
  geom_bar(aes(y = my_percentage, x = my_species, fill = category), data = df, stat="identity", width=my_bar_height) + 
  coord_flip() + 
  theme_gray(base_size = 8) + 
  #scale_y_continuous(labels = c("100","80","60","40","20","0"), breaks = c(100,80,60,40,20,0)) + 
  scale_y_continuous(labels = c("100","80","60","40","20","0"), breaks = c(100,80,60,40,20,0)) +
  #scale_y_continuous(labels = c("100","80","60","40","20","0"), breaks = c(0,20,40,60,80,100)) +
  scale_fill_manual(values = my_colors,labels =c(" Complete (C) and single-copy (S)  ",
                                                 " Complete (C) and duplicated (D)",
                                                 " Fragmented (F)  ",
                                                 " Missing (M)")) +   
  ggtitle(my_title) + 
  xlab("") + 
  ylab("\n%BUSCOs") + 

  theme(plot.title = element_text(family=my_family, colour = "black", size = rel(2.2)*my_size_ratio, face = "bold")) + 
  theme(legend.position="top",legend.title = element_blank()) + 
  theme(legend.text = element_text(family=my_family, size = rel(1.2)*my_size_ratio)) + 
  theme(panel.background = element_rect(color="#FFFFFF", fill="white")) + 
  theme(panel.grid.minor = element_blank()) + 
  theme(panel.grid.major = element_blank()) +
  theme(axis.text.y = element_text(family=my_family, colour = "black", size = rel(1.66)*my_size_ratio)) + 
  theme(axis.text.x = element_text(family=my_family, colour = "black", size = rel(1.66)*my_size_ratio)) + 
  theme(axis.line = element_line(size=1*my_size_ratio, colour = "black")) + 
  theme(axis.ticks.length = unit(.85, "cm")) + 
  theme(axis.ticks.y = element_line(colour="white", size = 0)) + 
  theme(axis.ticks.x = element_line(colour="#222222")) + 
  theme(axis.ticks.length = unit(0.4, "cm")) + 
  theme(axis.title.x = element_text(family=my_family, size=rel(1.2)*my_size_ratio)) + 

  guides(fill = guide_legend(override.aes = list(colour = NULL))) +
  guides(fill=guide_legend(nrow=2,byrow=TRUE))

  for(i in rev(c(1:length(levels(my_species))))){
    detailed_values <- my_values[my_species==my_species[my_species==levels(my_species)[i]]]
    total_buscos <- sum(detailed_values)
    figure <- figure + 
    annotate("text", label=paste("C:", detailed_values[1] + detailed_values[2], " [S:", detailed_values[1], ", D:", detailed_values[2], "], F:", detailed_values[3], ", M:", detailed_values[4], ", n:", total_buscos, sep=""), 
             y=3, x = i, size = labsize*4*my_size_ratio, colour = "black", hjust=0, family=my_family)
  }

my_output="~/temp.png"
ggsave(figure, file=my_output, width = my_width, height = my_height, unit = my_unit)
print("Done")

Answer 1

见 ?position_stack:

position_fill() and position_stack() automatically stack values in reverse order of the group aesthetic, which for bar charts is usually defined by the fill aesthetic (the default group aesthetic is formed by the combination of all discrete aesthetics except for x and y). This default ensures that bar colours align with the default legend.

为了改变堆叠方向，你只需要添加position = position_stack(reverse = TRUE)到geom_bar:

figure <- ggplot() +       
    geom_bar(
        aes(y = my_percentage, x = my_species, fill = category),
        data = df, stat="identity", width=my_bar_height,
        position = position_stack(reverse = TRUE)) + 
    coord_flip() + 
...

如果您不想使用 position_stack，则必须更改因子级别，并且您还必须设置填充颜色中断以保持相同的图例顺序。