tex2image: Transforming LaTeX Code Using ImageMagick or pdf2svg

Description

Transformation of LaTeX code into an image by compiling to PDF and then transforming to PNG (by default) via ImageMagick's convert command or to SVG via pdf2svg.

Usage

tex2image(tex, format = "png", width = NULL, pt = 12, density = 350,
  dir = NULL, tdir = NULL, idir = NULL,
  width.border = 0L, col.border = "white", resize = 650,
  packages = c("amsmath", "amssymb", "amsfonts"),
  header, header2 = NULL, tikz = NULL, Sweave = TRUE, show = FALSE,
  name = "tex2image")

Value

Character vector with path(s) to image(s) generated from the LaTeX code.

Arguments

tex: character vector or list of character vectors. Each character vector is either the name of a LaTeX file or a vector containing LaTeX code directly.
format: character. Suffix for the type of graphic to convert to.
width: numeric. Width of the text in inch. If NULL (or 0), the width is chosen to fit the image in tex.
pt: numeric. Pointsize of the text.
density: numeric. Resolution density of the image.
dir: character specifying the output directory.
tdir: character specifying a temporary directory, by default this is chosen via tempfile.
idir: character specifying the path additional LaTeX inputs required.
width.border: numeric. Width of the framebox border.
col.border: character. Color of framebox border.
resize: numeric. Number of pixels for resizing the image.
packages: character. Names of LaTeX packages to be included.
header: character. LaTeX code to be included in the header of the LaTeX file before the beginning of the document. By default the parindent is set to 0 and sans serif fonts (phv) are used for both text and math.
header2: character. LaTeX code to be included in the header of the LaTeX file after the beginning of the document.
tikz: character. Options to be passed to \usetikzlibrary{}. If set, the tikz package is loaded per default.
Sweave: logical. Should the LaTeX package Sweave.sty be included in the header?
show: logical. Show the resulting image(s) using browseURL.
name: character. Base name of the image file.

Details

tex2image converts LaTeX code to image files, e.g., for inclusion in web pages. It proceeds in the following steps: (1) LaTeX code is embedded into a suitable .tex file. (2) This is compiled to PDF using texi2dvi. (3) The PDF is converted to an image file. By default, conversion is to PNG using R package magick functionalities or alternatively to SVG via pdfcrop followed by pdf2svg.

The LaTeX code is fit into the standalone document class using the tikzpicture environment as a default.

If tex is a list of LaTeX chunks, then these are compiled to separate pages of a single PDF in a single LaTeX run. Each page is subsequently converted to a separate image.

In case of SVG output, the respective image manipulation tools, i.e., pdfcrop/pdf2svg, are assumed to be installed and available in the search path.

Examples

Run this code

if (FALSE) {
## some simple LaTeX
tex <- c("This is \\textbf{bold} and this \\textit{italic}.",
  "Points on the unit circle: $x^2 + y^2 = 1$.")

## default settings: PNG with sans serif fonts
tex2image(tex, show = interactive())

## with fixed widths
tex2image(tex, width = 6, show = interactive())
tex2image(tex, width = 2, show = interactive())

## switch off header (-> LaTeX uses its standard serif fonts)
tex2image(tex, header = NULL, show = interactive())

## SVG output (system requirements: pdfcrop & pdf2svg)
tex2image(tex, format = "svg", show = TRUE)
}