text: Q:
  
  Display a data.frame with mathematical notation in table header R Markdown html output
  
  Say I'd like to display a table of coefficients from several equations in an R Markdown file (html output). 
  I'd like the table to look somewhat like this:
  
  But I can't for the life of me figure out how to tell R Markdown to parse the column names in the table. 
  The closest I've gotten is a hacky solution using cat to print custom table from my data.frame... not ideal.  Is there a better way to do this?
  Here's how I created the image above, saving my file as an .Rmd in RStudio.
  ---
  title: "Math in R Markdown tables"
  output:
    html_notebook: default
    html_document: default
  ---
  
  My fancy table
  
  ```{r, echo=FALSE, include=TRUE, results="asis"}
  # Make data.frame
  mathy.df <- data.frame(site = c("A", "B"), 
                         b0 = c(3, 4), 
                         BA = c(1, 2))
  
  # Do terrible things to print it properly
  cat("Site|$\\beta_0$|$\\beta_A$")
  cat("\n")
  cat("----|---------|---------\n")
  
  for (i in 1:nrow(mathy.df)){
    cat(as.character(mathy.df[i,"site"]), "|", 
        mathy.df[i,"b0"], "|", 
        mathy.df[i,"BA"], 
        "\n", sep = "")
  }
  ```
  
  A:
  
  You can use kable() and its escape option to format math notation (see this answer to a related question). Then you assign your mathy headings as the column names, and there you go:
  ---
  title: "Math in R Markdown tables"
  output:
    html_notebook: default
    html_document: default
  ---
  
  My fancy table
  
  ```{r, echo=FALSE, include=TRUE, results="asis"}
  library(knitr)
  
  mathy.df <- data.frame(site = c("A", "B"), 
                         b0 = c(3, 4), 
                         BA = c(1, 2))
  
  colnames(mathy.df) <- c("Site", "$\\beta_0$", "$\\beta_A$")
  
  kable(mathy.df, escape=FALSE)
  ```
  
  