render
Render R Markdown
Render the input file to the specified output format using
pandoc. If the input requires knitting then
knit
is called prior to pandoc.
Usage
render(input, output_format = NULL,
output_file = NULL, output_options = NULL,
clean = TRUE, envir = parent.frame(), quiet = FALSE,
encoding = getOption("encoding"))
Arguments
- input
Input file (Rmd or plain markdown)
- output_format
R Markdown output format to convert to. This can be a character vector with the name of a format; e.g.
"html_document"
. Alternatively it can be an output format object; e.g.html_document()
. IfNULL
is passed then the output format is read from the YAML metadata within the input file (defaulting to HTML if no format is specified in metadata).- output_options
List of output options that can override the options specified in metadata (e.g. could be used to force
self_contained
ormathjax = "local"
). Note that this is only valid when the output format is read from metadata (i.e. not a custom format object passed tooutput_format
)- output_file
Output file (if not specified then a default based on the specified output format is chosen)
- clean
TRUE
to clean intermediate files created during rendering.- envir
The environment in which the code chunks are to be evaluated during knitting (can use
new.env()
to guarantee an empty new environment)- quiet
TRUE
to supress printing of the pandoc command line- encoding
the encoding of the input file; see
file
Details
If no output_format
parmaeter is specified then the output
format is read from the YAML front-matter of the input
file. For example, the following YAML would yield a PDF
document:
output: pdf_document
Additional format options can also be specified in metadata. For example:
output: pdf_document: toc: true highlight: zenburn
Multiple formats can be specified in metadata. If no output_format
is passed to render
then the first one defined will be used:
output: pdf_document: toc: true highlight: zenburn html_document: toc: true theme: united
Formats specified in metadata can be any one of the built in formats
(e.g. html_document
,
pdf_document
) or a format defined in another
package (e.g. pkg::custom_format
).
If there is no format defined in the YAML then
html_document
will be used.
Value
The compiled document is written into the output file, and the path of the output file is returned.
R Markdown
R Markdown supports all of the base pandoc markdown
features as well as some optional features for
compatibility with GitHub Flavored Markdown (which
previous versions of R Markdown were based on). See
rmarkdown_format
for details.