knit_print.flextable: Render flextable in rmarkdown

Description

Function used to render flextable in knitr/rmarkdown documents.

You should not call this method directly. This function is used by the knitr package to automatically display a flextable in an "R Markdown" document from a chunk. However, it is recommended to read its documentation in order to get familiar with the different options available.

HTML, Word, PowerPoint and PDF outputs are supported.

Table captioning is a flextable feature compatible with R Markdown documents. The feature is available for HTML, PDF and Word documents. Compatibility with the "bookdown" package is also ensured, including the ability to produce captions so that they can be used in cross-referencing.

Usage

# S3 method for flextable
knit_print(x, ...)

Arguments

a flextable object

...

further arguments, not used.

Chunk options

Some features, often specific to an output format, are available to help you configure some global settings relatve to the table output. knitr's chunk options are to be used to change the default settings:

chunk option	property	default value	HTML	docx	PDF	pptx
ft.align	flextable alignment, supported values are 'left', 'center' and 'right'	'center'	yes	yes	yes	no
ft.shadow	HTML option, disable shadow dom (set to `FALSE`) for pagedown.	TRUE	yes	no	no	no
ft.split	Word option 'Allow row to break across pages' can be activated when TRUE.	FALSE	no	yes	no	no
ft.tabcolsep	space between the text and the left/right border of its containing cell	8.0	no	no	yes	no
ft.arraystretch	height of each row relative to its default height	1.5	no	no	yes	no
ft.left	left coordinates in inches	1.0	no	no	no	yes

Table caption

Captions can be defined in two ways.

The first is with the set_caption function. If it is used, the other method will be ignored. The second method is by using knitr chunk option tab.cap.

set_caption(x, caption = "my caption")

If set_caption function is not used, caption identifier will be read from knitr's chunk option tab.id or label if in a bookdown (this is to respect the bookdown standards).

tab.id='my_id' or label='my_id'

Word output provide more options such as ability to choose the prefix for numbering chunk for example. The table below expose these options:

chunk option	purpose	rmarkdown	bookdown
tab.cap.style	(Word only) style name to use for table captions	yes	yes
tab.cap.pre	(Word only) Prefix for numbering chunk (default to "Table")	yes	yes
tab.cap.sep	(Word only) Suffix for numbering chunk (default to ": ")	yes	yes
tab.cap	Caption label	yes	yes
tab.id	Caption reference unique identifier	yes	no

HTML output

HTML output is using shadow dom to encapsule the table into an isolated part of the page so that no clash happens with styles. Some output may not support this feature. To our knowledge, only the pagedown output is concerned. Use knitr chunk option ft.shadow=FALSE to disable shadow dom.

PDF output

Some features are not implemented in PDF due to technical infeasibility. These are the padding, line_spacing and height properties.

PowerPoint output

Auto-adjust Layout is not available for PowerPoint.

Also images cannot be integrated into tables with the PowerPoint format.

Examples

Run this code

# NOT RUN {
# simple examples -----
demo_docx <- system.file(package = "flextable", "examples/rmd", "demo.Rmd")
rmd_file <- tempfile(fileext = ".Rmd")
file.copy(demo_docx, to = rmd_file, overwrite = TRUE)
rmd_file # R Markdown document used for demo
if(require("rmarkdown", quietly = TRUE)){
#  knitr::opts_chunk$set(webshot = "webshot2")
#  render(input = rmd_file, output_format = "word_document", output_file = "doc.docx")
#  render(input = rmd_file, output_format = "pdf_document", output_file = "doc.pdf")
#  render(input = rmd_file, output_format = "html_document", output_file = "doc.html")
#  render(input = rmd_file, output_format = "powerpoint_presentation", output_file = "pres.pptx")
#  render(input = rmd_file, output_format = "slidy_presentation", output_file = "slidy.html")
#  render(input = rmd_file, output_format = "beamer_presentation", output_file = "beamer.pdf")
#  render(input = rmd_file, output_format = "pagedown::html_paged", output_file = "paged.html")
}


## bookdown examples wth captions and cross ref -----
# captions_example <- system.file(
#   package = "flextable",
#   "examples/rmd", "captions_example.Rmd")
#
# dir_tmp <- tempfile(pattern = "dir")
# dir.create(dir_tmp, showWarnings = FALSE, recursive = TRUE)
# file.copy(captions_example, dir_tmp)
# rmd_file <- file.path(dir_tmp, basename(captions_example))
#
# file.copy(captions_example, to = rmd_file, overwrite = TRUE)
#
# if(require("rmarkdown", quietly = TRUE)){
#   render(input = rmd_file,
#          output_format = word_document(),
#          output_file = "doc.docx")
#   render(input = rmd_file,
#          output_format = pdf_document(latex_engine = "xelatex"),
#          output_file = "doc.pdf")
#   render(input = rmd_file,
#          output_format = html_document(),
#          output_file = "doc.html")
#
#   # bookdown ----
#   if(require("bookdown", quietly = TRUE)){
#     render(input = rmd_file, output_format = word_document2(),
#            output_file = "book.docx")
#     render(input = rmd_file,
#            output_format = pdf_document2(latex_engine = "xelatex"),
#            output_file = "book.pdf")
#     render(input = rmd_file,
#            output_format = html_document2(),
#            output_file = "book.html")
#
#     # officedown ----
#     if(require("officedown", quietly = TRUE)){
#       render(input = rmd_file,
#              output_format = markdown_document2(base_format=rdocx_document),
#              output_file = "officedown.docx")
#     }
#   }
# }
# browseURL(dirname(rmd_file))


# }

Run the code above in your browser using DataLab

Data Engineering and BI courses are free this week!