R-knitr:kable-删除单个标题并在多个列上添加单个标题

R标记文件中的R代码：

col1 <- c("dummydata","dummydata","dummydata")
col2 <- c("dummydata","dummydata","dummydata")  
col3 <- c("dummydata","dummydata","dummydata")
col4 <- c("dummydata","dummydata","dummydata")
col5 <- c("dummydata","dummydata","dummydata")
col6 <- c("dummydata","dummydata","dummydata")
col7 <- c("dummydata","dummydata","dummydata")
col8 <- c("dummydata","dummydata","dummydata")

df1 <- data.frame(col1,col2,col3,col4,col5,col6,col7,col8)

kable(df1, format="html",table.attr='class="myTable"') %>%
kable_styling(bootstrap_options = c("striped", "hover", "condensed", "responsive")) %>%
add_header_above(c("Group1" = 2, "Group2" = 2,"Group3" = 2, "Group4" = 2))

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col1如果您经常遇到此类问题，您应该熟悉正则表达式和gsub函数

这里有一个解决方案，第一行是您的最后一行代码，通过“x谢谢。我实际上知道正则表达式（基础）。我正在努力解决的是Rmd文件生成html文件。您正在使用该html文件来应用正则表达式，对吗？是的，这基本上就是它的工作方式，取决于您想要什么和如何执行。
x <- kable(df1, format="html",table.attr='class="myTable"') %>%
kable_styling(bootstrap_options = c("striped", "hover", "condensed", "responsive")) %>%
add_header_above(c("Group1" = 2, "Group2" = 2,"Group3" = 2, "Group4" = 2))

gsub("</th></tr><tr>.*</thead>","</thead>",x)