r - 从函数调用将变量传递给 ggpubr

Question

我希望将以下公式包装到一个函数中以便于最终使用:

df %>% 
  group_by(a, b) %>%
  summarize(avg=mean(c)) %>%
  ggline(x="a", y="avg", color='b')

但是，即使 is.factor(df$b) == TRUE，以下内容也会返回错误“is.factor(x) 中的错误:对象 'b' 未找到”

graph_var <- function(data_source, var) {
  var2 <- enquo(var)
  
  data_source %>% 
    group_by(a, !!var2 )%>% 
    summarize(avg=mean(c)) %>% 
    ggline(x="a", y="avg", color=shQuote(var) )+ grids(linetype = 'dashed')
}

graph_var(df, b)

我确定问题出在 ggpubr 周围的某个地方，在其参数中使用引号，但我无法准确地找到我需要做什么才能使其正常工作。

为了重现性:

library(tidyverse)
library(ggpubr)

set.seed(13)
df <- data.frame(
  a = rep(1:10),
  b = as.factor(rep(LETTERS[24:26], each = 10)),
  c = rnorm(30)
)

#explicit declatation - this works
df %>% 
  group_by(a, b )%>% 
  summarize(avg=mean(c)) %>% 
  ggline(x="a", y="avg", color="b" )+ grids(linetype = 'dashed') #works

#declaired via variable, this also works
test_var <- "b"

df %>% 
  group_by(a, b )%>% 
  summarize(avg=mean(c)) %>% 
  ggline(x="a", y="avg", color=test_var )+ grids(linetype = 'dashed') #also works

#declaited via f(x) - yeilds error "Error in is.factor(x) : object 'b' not found"
graph_var_ex <- function(data_source, var) {
  var2 <- enquo(var)
  
  data_source %>% 
    group_by(a, !!var2 )%>% 
    summarize(avg=mean(c)) %>% 
    ggline(x="a", y="avg", color=shQuote(var) )+ grids(linetype = 'dashed')
}

graph_var_ex(df, b)

Answer 1

尝试as.character(ensym(var)) .

其他说明:

1. 您的职能包括y="c"在 ggline()打电话，但这应该是 y="avg"自 "c"在您的 summarize() 之后不再存在.
2. 您可以使用 {{ embracing operator作为 !!enquo() 的快捷方式经过时var至group_by() .

library(dplyr)
library(ggpubr)

# example data
set.seed(13)
df <- data.frame(
  a = rep(1:10),
  b = rep(LETTERS[24:26], each = 10),
  c = rnorm(30)
)

graph_var <- function(data_source, var) {
  var2 <- as.character(ensym(var))
  
  data_source %>% 
    group_by(a, {{var}})%>% 
    summarize(avg = mean(c)) %>% 
    ggline(x = "a", y = "avg", color = var2) + 
    grids(linetype = "dashed")
}

graph_var(df, b)