11.3 LaTeX fragments

With symbols, sub- and superscripts, HTML is pretty much at its end when it comes to representing mathematical formulas¹. More complex expressions need a dedicated formula processor. To this end, Org mode can contain arbitrary LaTeX fragments. It provides commands to preview the typeset result of these fragments, and upon export to HTML, all fragments will be converted to images and inlined into the HTML document². For this to work you need to be on a system with a working LaTeX installation. You also need the dvipng program, available at http://sourceforge.net/projects/dvipng/. The LaTeX header that will be used when processing a fragment can be configured with the variable org-format-latex-header.

LaTeX fragments don't need any special marking at all. The following snippets will be identified as LaTeX source code:

• Environments of any kind. The only requirement is that the \begin statement appears on a new line, preceded by only whitespace.
• Text within the usual LaTeX math delimiters. To avoid conflicts with currency specifications, single `$' characters are only recognized as math delimiters if the enclosed text contains at most two line breaks, is directly attached to the `$' characters with no whitespace in between, and if the closing `$' is followed by whitespace or punctuation. For the other delimiters, there is no such restriction, so when in doubt, use `\(...\)' as inline math delimiters.

For example:

     \begin{equation}                          % arbitrary environments,
     x=\sqrt{b}                                % even tables, figures
     \end{equation}                            % etc
     
     If $a^2=b$ and \( b=2 \), then the solution must be
     either $$ a=+\sqrt{2} $$ or \[ a=-\sqrt{2} \].

If you need any of the delimiter ASCII sequences for other purposes, you can configure the option org-format-latex-options to deselect the ones you do not wish to have interpreted by the LaTeX converter.