hpdf_document_base: A basic PDF document output format
In RLesur/weasydoc: Convert R Markdown to PDF Using HTML and CSS

This output format is compatible with the htmltools package.

hpdf_document_base(toc = FALSE, toc_depth = 3, number_sections = FALSE,
  section_divs = TRUE, fig_width = 5, fig_height = 4, fig_retina = 8,
  fig_caption = TRUE, dev = "png", dpi = 96, df_print = NULL,
  notes = c("endnotes", "footnotes"), attach_code = FALSE, smart = TRUE,
  highlight = "default", math_engine = "webtex_svg", template = NULL,
  html_format = c("html4", "html5"), engine = c("weasyprint", "prince"),
  engine_opts = NULL, extra_dependencies = NULL, css = NULL,
  includes = NULL, keep_md = FALSE, keep_html = FALSE,
  self_contained = TRUE, lib_dir = NULL, md_extensions = NULL,
  pandoc_args = NULL, ...)

`toc`	`TRUE` to include a table of contents in the output
`toc_depth`	Depth of headers to include in table of contents
`number_sections`	`TRUE` to number section headings
`section_divs`	Wrap sections in <div> tags (or <section> tags in HTML5), and attach identifiers to the enclosing <div> (or <section>) rather than the header itself.
`fig_width`	Default width (in inches) for figures
`fig_height`	Default width (in inches) for figures
`fig_retina`	Setting this option to a ratio (for example, 2) will change the `dpi` parameter to `dpi * fig.retina`, and `fig_width` to `fig_width * dpi / fig_retina` internally; for example, the physical size of an image is doubled and its display size is halved when `fig_retina = 2`.
`fig_caption`	`TRUE` to render figures with captions
`dev`	Graphics device to use for figure output (defaults to png)
`dpi`	The DPI (dots per inch) for bitmap devices.
`df_print`	Method to be used for printing data frames. Valid values include `"default"`, `"kable"` and `"tibble"`. The `"default"` method uses `print.data.frame`. The `"kable"` method uses the `knitr::kable()` function. The `"tibble"` method uses the tibble::tibble-package to print a summary of the data frame. In addition to the named methods you can also pass an arbitrary function to be used for printing data frames. You can disable the `df_print` behavior entirely by setting the option `rmarkdown.df_print` to `FALSE`.
`notes`	Render notes as endnotes or footnotes. Footnotes are not yet supported by WeasyPrint and are only well rendered with Prince.
`attach_code`	Add the `Rmd` source code as an attachment to the `PDF` document.
`smart`	Produce typographically correct output, converting straight quotes to curly quotes, — to em-dashes, – to en-dashes, and ... to ellipses.
`highlight`	Syntax highlighting style. Supported styles include "default", "tango", "pygments", "kate", "monochrome", "espresso", "zenburn", "haddock", and "textmate". Pass `NULL` to prevent syntax highlighting.
`math_engine`	Method to be used to render `TeX` math. Valid values include `"unicode"`, `"mathjax"`, `"mathml"`, `"webtex_svg"`, `"webtex_png"` and `"katex"`. See the pandoc manual for details.
`template`	`Pandoc` template to use for rendering. Pass `NULL` to use `pandoc`'s built-in template; pass a path to use a custom template that you've created. See the documentation on pandoc online documentation for details on creating custom templates.
`html_format`	HTML format of the intermediate HTML file.
`engine`	A `PDF` engine.
`engine_opts`	A character vector of command-line arguments to be passed to `engine`.
`extra_dependencies`	Additional function arguments to pass to the base R Markdown HTML output formatter `html_document_base`
`css`	One or more css files to include
`includes`	Named list of additional content to include within the document (typically created using the `includes` function).
`keep_md`	Keep the markdown file generated by knitting.
`keep_html`	Keep intermediate `HTML` file.
`self_contained`	Use `self_contained` to indicate if external dependencies are embedded in `HTML` file.
`lib_dir`	Directory to copy dependent HTML libraries (e.g. jquery, bootstrap, etc.) into. By default this will be the name of the document with `_files` appended to it.
`md_extensions`	Markdown extensions to be added or removed from the default definition or R Markdown. See the `rmarkdown_format` for additional details.
`pandoc_args`	Additional command line options to pass to pandoc
`...`	Additional arguments passed to `rmarkdown::html_document_base()`.