Render the input file to the specified output format using pandoc. If the
input requires knitting then knit
is called prior
to pandoc.
render(input, output_format = NULL, output_file = NULL,
output_dir = NULL, output_options = NULL, intermediates_dir = NULL,
knit_root_dir = NULL, runtime = c("auto", "static", "shiny",
"shiny_prerendered"), clean = TRUE, params = NULL,
knit_meta = NULL, envir = parent.frame(), run_pandoc = TRUE,
quiet = FALSE, encoding = "UTF-8")
The input file to be rendered. This can be an R script (.R), an R Markdown document (.Rmd), or a plain markdown document.
The R Markdown output format to convert to. The option
"all"
will render all formats defined within the file. The option can
be the name of a format (e.g. "html_document"
) and that will render
the document to that single format. One can also use a vector of format
names to render to multiple formats. Alternatively, you can pass an output
format object (e.g. html_document()
). If using NULL
then the
output format is the first one defined in the YAML frontmatter in the input
file (this defaults to HTML if no format is specified there).
The name of the output file. If using NULL
then the
output filename will be based on filename for the input file. If a filename
is provided, a path to the output file can also be provided. Note that the
output_dir
option allows for specifying the output file path as well,
however, if also specifying the path, the directory must exist. If
output_file
is specified but does not have a file extension, an
extension will be automatically added according to the output format. To
avoid the automatic file extension, put the output_file
value in
I()
, e.g., I('my-output')
.
The output directory for the rendered output_file
.
This allows for a choice of an alternate directory to which the output file
should be written (the default output directory of that of the input file).
If a path is provided with a filename in output_file
the directory
specified here will take precedence. Please note that any directory path
provided will create any necessary directories if they do not exist.
List of output options that can override the options
specified in metadata (e.g. could be used to force self_contained
or
mathjax = "local"
). Note that this is only valid when the output
format is read from metadata (i.e. not a custom format object passed to
output_format
).
Intermediate files directory. If a path is specified
then intermediate files will be written to that path. If NULL
,
intermediate files are written to the same directory as the input file.
The working directory in which to knit the document;
uses knitr's root.dir
knit option. If NULL
then the behavior
will follow the knitr default, which is to use the parent directory of the
document.
The runtime target for rendering. The static
option
produces output intended for static files; shiny
produces output
suitable for use in a Shiny document (see run
). The default,
auto
, allows the runtime
target specified in the YAML metadata
to take precedence, and renders for a static
runtime target otherwise.
Using TRUE
will clean intermediate files that are created
during rendering.
A list of named parameters that override custom params
specified within the YAML front-matter (e.g. specifying a dataset to read or
a date range to confine output to). Pass "ask"
to start an
application that helps guide parameter configuration.
(This option is reserved for expert use.) Metadata generated by knitr.
The environment in which the code chunks are to be evaluated
during knitting (can use new.env()
to guarantee an empty new
environment).
An option for whether to run pandoc to convert Markdown output.
An option to suppress printing of the pandoc command line.
The encoding of the input file. See file
for
more information.
When run_pandoc = TRUE
, the compiled document is written into
the output file, and the path of the output file is returned. When
run_pandoc = FALSE
, the path of the Markdown output file, with
attributes knit_meta
(the knitr meta data collected from code
chunks) and intermediates
(the intermediate files/directories
generated by render()
).
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.
Note that the knitr error
option is set to FALSE
during
rendering (which is different from the knitr default value of
TRUE
).
For additional details on rendering R scripts see Compiling R scripts to a notebook.
If no output_format
parameter 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.
# NOT RUN {
library(rmarkdown)
# Render the default (first) format defined in the file
render("input.Rmd")
# Render all formats defined in the file
render("input.Rmd", "all")
# Render a single format
render("input.Rmd", "html_document")
# Render multiple formats
render("input.Rmd", c("html_document", "pdf_document"))
# }
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