When plots are not generated from R code, there is no way for knitr to
capture plots automatically. In this case, you may generate the images
manually and pass their file paths to this function to include them in the
output. The major advantage of using this function is that it is portable in
the sense that it works for all document formats that knitr supports,
so you do not need to think if you have to use, for example, LaTeX or
Markdown syntax, to embed an external image. Chunk options related to
graphics output that work for normal R plots also work for these images, such
as out.width and out.height.
include_graphics(path, auto_pdf = getOption("knitr.graphics.auto_pdf", FALSE),
dpi = NULL)A character vector of image paths.
Boolean; whether to use PDF images automatically when the output
format is LaTeX. If TRUE, then e.g. foo/bar.png will be replaced by
foo/bar.pdf if the latter exists. This can be useful since normally
PDF images are of higher quality than raster images like PNG, when the
output is LaTeX/PDF.
DPI (dots per inch) value. Used to calculate the output
width (in inches) of the images. This will be their actual width in pixels,
divided by dpi. If not provided, the chunk option dpi is used; if
NA, the output width will not be calculated.
The same as the input character vector path but it is marked
with special internal S3 classes so that knitr will convert the file
paths to proper output code according to the output format.