使用因子变量R手动更改y轴刻度标记

Question

我有以下数据：

id <- rep(1:100)
A <- rep(c(0.12 ,0.25, 0.5, 1, 2), each = 20)
B <- rep(c(0.06, 0.03, 0.015, 0.12), each = 25)
C <- rep(c(0.015, 0.03, 0.06, 0.12, 0.25), each = 20)

df <- data.frame(id,A,B,C,stringsAsFactors = F)

我把A，B和C分成两列。请注意，A，B和C列实际上是因素，我只是避免将它们指定为创建小提琴图的因素。

library(dplyr)

df_edited <- df %>%
  gather(key, value, -id, factor_key = F)

我用这些数据创建了以下图：

library(ggplot2)

factor_breaks <- c(0.015,0.03,0.06,0.12,0.25,0.5,1,2)
factor_levels <- c("0.015","0.03","0.06","0.12","0.25","0.5","1","2")

ggplot(df_edited, aes(key, value))+
  geom_violin()+
  scale_y_continuous(labels = factor_levels, breaks = factor_breaks)

这会创建以下图表：

是否可以使y轴标签安全放置，如下图所示，并确保小提琴图是否正确？

ggplot(df_edited, aes(key, factor(value)))+
  geom_violin()

Answer 1

一种选择是转换y轴的值

ggplot(df_edited, aes(key, value))+
 geom_violin()+
 scale_y_continuous(labels = factor_levels,
                    breaks = factor_breaks,
                    trans = 'log10')

Answer 2

虽然log10也可以在这个例子中使用，但我认为更通用到＆＃34; rescale＆＃34;使用sapply：

的值

df_edited$newValue <- sapply(as.character(df_edited$value), 
                             function(x){which(factor_levels == x)})

这基本上返回factors_levels向量中值的位置。

ggplot(df_edited, aes(key, newValue))+
  geom_violin() + 
  scale_y_continuous(breaks = 1:length(factor_levels), 
                     labels = factor_levels)