knitr (version 1.52)

hook_plot_html: Default plot hooks for different output formats

Description

These hook functions define how to mark up graphics output in different output formats.

Usage

hook_plot_html(x, options)
hook_plot_asciidoc(x, options)
hook_plot_tex(x, options)
hook_plot_md(x, options)
hook_plot_rst(x, options)
hook_plot_textile(x, options)
hook_plot_typst(x, options)

Value

A character string of code, with plot filenames wrapped.

Arguments

x

Filename for the plot (a character string).

options

A list of the current chunk options.

Details

Depending on the options passed over, hook_plot_tex may return the normal \includegraphics{} command, or \input{} (for tikz files), or \animategraphics{} (for animations); it also takes many other options into consideration to align plots and set figure sizes, etc. Similarly, hook_plot_html, hook_plot_md and hook_plot_rst return character strings which are HTML, Markdown, reST code.

For animations (i.e. when the chunk option fig.show is 'animate'), hook_plot_tex generates \animategraphics{} unless a hook function has been provided via the chunk option animation.hook or the package option animation.fun, in which case that function generates the LaTeX code instead. It is called only once per chunk, with the filename of the last plot. The built-in hooks (e.g. hook_ffmpeg_html()) generate HTML, and are ignored for LaTeX output.

In most cases we do not need to call these hooks explicitly, and they were designed to be used internally. Sometimes we may not be able to record R plots using grDevices::recordPlot(), and we can make use of these hooks to insert graphics output in the output document; see hook_plot_custom() for details.

References

https://yihui.org/knitr/hooks/

See Also

hook_plot_custom()

Examples

# this is what happens for a chunk like this

# <>=
hook_plot_tex("foo-bar-plot.pdf", opts_chunk$merge(list(fig.align = "right")))

# <>=
hook_plot_tex("bar.tikz", opts_chunk$merge(list(dev = "tikz")))

# <>=

# 5 plots are generated in this chunk
hook_plot_tex("foo5.pdf", opts_chunk$merge(list(fig.show = "animate", interval = 0.1,
    fig.cur = 5, fig.num = 5)))