将col名称和标题（上图）设置为具有knitr，kableExtra和Latex in R markdown的表格的奇怪字符

Question

我试图根据钻石数据集在Rmarkdown（for pdf）中创建一个表格，我想在列名称上面更改一些列名和标题，我想知道如何设置一些标题以斜体或粗体显示，某些标题应为符号（如部分eta平方的符号）或完整的公式。我已将我的R代码（我已经安装了Latex）与表格作为图片（尚未调整）。

```{r setup, include=FALSE}

setwd("~/Desktop/Tables") 
knitr::opts_chunk$set(echo = FALSE)
# global options
options(knitr.table.format = "latex") 
# show space instead of NA in tables
options(knitr.kable.NA = '')
library(tidyverse)
library(knitr)
library(kableExtra)
df = diamonds

```

```{r message=FALSE, warning=FALSE}

df_table = df %>% 
  summarise(avg = round(mean(price), 2),
            sd = round(sd(price), 2),
            n = n(),
            range = round(max(price), 2)) %>% 
  mutate(grouping = "Total") %>% 
  select(grouping, avg, sd, n, range) %>% 
  bind_rows(df %>% 
              group_by(cut) %>% 
              summarise(avg = round(mean(price), 2),
              sd = round(sd(price), 2),
              n = n(),
              range = round(max(price), 2)) %>% 
              mutate(grouping = as.character(cut)) %>% 
              select(grouping, avg, sd, n, range))

kable(df_table,
      booktabs = TRUE,
      linesep = "",
      col.names = c("Grouping", "M in italic", "SD in italic", "N not 
italic", "some weird formula for the range" )) %>%
  kable_styling(latex_options = c("HOLD_position", "scale_down")) %>% 
  add_header_above(c(" " = 1, "the formula for the variance" = 4))

```

Answer 1

在致电escape = FALSE和kable时设置add_header_above，并在列标题中使用LaTeX。我应该承认，对我来说，确切地说应该添加多少反斜杠以获得理想的结果是个谜。

kable(df_table,
      booktabs = TRUE,
      linesep = "",
      col.names = c("Grouping", "$M$", "$SD$", "N", "$\\eta$"), escape = FALSE) %>%
  kable_styling(latex_options = c("HOLD_position", "scale_down")) %>% 
  add_header_above(c(" " = 1, "$\\\\operatorname{Var}[X]$" = 4), escape = FALSE)