How to disable automatically insert linebreak in need?

Question

I have install a plugin named latex for wordpress, which use mathjax to render the latex mathematical symbols.

An matrix example

$$\mathbf{P} = \left[ \begin{matrix} x\ y\ \end{matrix} \right],\mathbf{P'} = \left[ \begin{matrix} x\ y\ \end{matrix} \right],\mathbf{T} = \left[ \begin{matrix} t_{x}\ t_{y}\ \end{matrix} \right] $$

The problem is I could not break the statement into multiple lines when the statement become too long in a single line. Because wordpress would automatically insert <br> to the equation.

So I need to disable automatically generation of <br> in and only in this circumstances.

Could I do this with some extra tags?

Answer 1

Assuming, you're using a latex shortcode, the following should do what you've asked for:

function leave_latex_alone($content) {
    $new_content = '';
    $pattern_full = '{(\[latex\].*?\[/latex\])}is';
    $pattern_contents = '{\[latex\](.*?)\[/latex\]}is';
    $pieces = preg_split($pattern_full, $content, -1, PREG_SPLIT_DELIM_CAPTURE);

    foreach ($pieces as $piece)
        if (preg_match($pattern_contents, $piece, $matches)) $new_content .= $matches[1];
        else $new_content .= wptexturize(wpautop($piece));

    return $new_content;
}

remove_filter('the_content', 'wpautop');
remove_filter('the_content', 'wptexturize');

add_filter('the_content', 'leave_latex_alone', 99);

This is an adapted version of some code found here. However, I did not test the code.