You don’t necessary need to author an R Markdown document to create a dynamic report. In fact, you can take any R script and compile it into a report that includes commentary, source code, and script output. Reports can be compiled to any output format including HTML, PDF, MS Word, and Markdown.

To compile a report from an R script you simply pass the script to render. For example:

rmarkdown::render("analysis.R", "pdf_document")

The first call to render creates an HTML document, whereas the second creates a PDF document.

If you are using RStudio then you can also create a report using the Compile Report command (Ctrl+Shift+K).


By default the name of the script, username, and current date and time are included in the header of the report You can override this default behavior by including metadata in a specially formatted R comment:

#' ---
#' title: "Crop Analysis Q3 2013"
#' author: "John Smith"
#' date: "May 3rd, 2014"
#' ---

You can also specify the output format within the metadata, for example:

#' ---
#' title: "Crop Analysis Q3 2013"
#' output: pdf_document
#' ---

Markdown Formatting

Note that the R comment used above to add a title, author, and date includes a single-quote as a special prefix character. This is a roxygen2 style comment, and it’s actually possible to include many such comments in an R script, all of which will be converted to markdown content within the compiled report For example:

#' A script comment that includes **markdown** formatting.

Rather than displaying as an R comment in the compiled report any roxygen2 style comment will be treated as markdown and rendered accordingly.

knitr Spin

Including markdown within R comments is possible because rmarkdown::render calls the knitr::spin function to convert the R script to an Rmd file. The spin function also enables you to add knitr chunk options with another special comment prefix (#+). For example:

#+ fig.width=5, fig.height=5

For more information on using spin see:

Note that when using rmarkdown::render the spin function is called automatically under the hood as part of rendering.

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