HTML output with kable

The knitr package has good functionality (via kable) for printing HTML tables. The basic format is

kable(x, format = 'html')

Most of the good parts of this format come with the kableExtra package, however. You can use the kable_styling function to customize the look of your table.

library(kableExtra)
head(iris) %>%
  kable() %>%
  kable_styling(bootstrap_options = "striped",
                full_width = FALSE,
                position = "center")

PDF output with xtable

For a PDF document, typically a nice LaTeX table will be a good fit, which you can create with xtable.

library(xtable)
data(tli)
print(xtable(head(tli)), type = "latex", booktabs = TRUE)

This table specifically is an image from a knitted PDF version - if you use xtable with an HTML output, the resulting table will not format as nicely.

To use xtable in an R markdown chunk, add the option results = 'asis' to your chunk. One nice table style uses the booktabs setting, which you can invoke by adding the following line to the YAML header of your Markdown file:

header-includes:
   - \usepackage{booktabs}

The above code makes sure your file can access the LaTeX package bookdown when it knits. (This is important because bookdown contains instructions for creating that style.)