PDF and LaTeX

Render flextable tables in PDF documents via knitr, configure LaTeX engines, and control float behavior.

When knitting to PDF, knit_print.flextable() automatically generates LaTeX code. No setup is required beyond a working LaTeX installation.

LaTeX engine requirements

The default pdflatex engine does not support custom font families. If your tables use system fonts (set via set_flextable_defaults(font.family = ...)), you must switch to xelatex or lualatex.

Set the engine in the YAML header of your R Markdown or Quarto document:

R Markdown

---
title: "My document"
output:
  pdf_document:
    latex_engine: xelatex
---

Quarto

---
title: "My document"
format:
  pdf:
    pdf-engine: xelatex
---

Alternatively, suppress the font warning and keep using pdflatex by setting:

set_flextable_defaults(fonts_ignore = TRUE)

Required LaTeX packages

flextable automatically loads the following LaTeX packages via knitr metadata:

• fontspec (xelatex/lualatex only)
• multirow, multicol
• colortbl
• ulem
• hhline
• longtable
• array
• hyperref

Adding dependencies manually with add_latex_dep()

When chunk caching is enabled, knitr uses the cached output and skips the chunk that would normally register LaTeX dependencies. Call add_latex_dep() in a non-cached chunk to ensure the dependencies are included:

# In a non-cached setup chunk:
add_latex_dep()

If your tables use float or wrap containers, pass the corresponding arguments:

add_latex_dep(float = TRUE, wrapfig = TRUE)

Chunk options for PDF

Control LaTeX rendering per-chunk or globally:

# Set globally in a setup chunk
knitr::opts_chunk$set(
  ft.tabcolsep = 4,
  ft.arraystretch = 1.8,
  ft.latex.float = "none"
)

Chunk option	Description	Default
ft.tabcolsep	Space (pt) between text and left/right cell border	0
ft.arraystretch	Row height multiplier	1.5
ft.latex.float	Float container type	"none"

These can also be set directly on the table object with set_table_properties():

ft <- set_table_properties(
  ft,
  opts_pdf = list(
    tabcolsep = 4,
    arraystretch = 1.8
  )
)

Float behavior

The ft.latex.float chunk option (or set_table_properties(float = ...)) controls how the LaTeX table is wrapped:

Value	Container	Description
"none"	No container	Table appears inline at its location
"float"	float package	Table floats to optimal position
"wrap-r"	wrapfig package	Text wraps around right side
"wrap-l"	wrapfig package	Text wraps around left side
"wrap-i"	wrapfig package	Inner margin (for two-column)
"wrap-o"	wrapfig package	Outer margin (for two-column)

Example using a float container:

```{r ft.latex.float="float"}
ft <- flextable(head(iris))
ft <- set_caption(ft, caption = "Iris data sample")
ft
```

PDF limitations

The following formatting properties have no effect in PDF output:

• padding.top and padding.bottom
• line_spacing
• Row height
• Justified text alignment (converted to left-aligned)
• Images inside table cells
• Equations (as_equation()) and hyperlinks

Images inside flextable cells are not rendered in PDF/LaTeX output.

Font families

With xelatex or lualatex, flextable loads the fontspec package and applies font families defined on text runs. The font must be installed on your system.

To use the Liberation Sans font (included with the gdtools package):

library(gdtools)
register_liberationsans()
set_flextable_defaults(font.family = "Liberation Sans")

To avoid font-related errors with pdflatex, fall back to LaTeX default fonts:

set_flextable_defaults(fonts_ignore = TRUE)