# Breaking long formula at specific characters

I have some rather long formulas that are not equations, and I would like LaTeX to break them automatically whenever necessary, preferably at the \vee symbol. I currently use the breqn package and the dmath environment, but that insists on breaking my lines on < and =, which is absolutely not what I want.

\begin{dmath}[number={$S_{1,19}$}] p_{19,a} < p_{1,a} \myvee p_{19,a} + p_{19,b} < p_{1,a} + p_{1,b} \myvee p_{19,a} = p_{1,a} \wedge p_{19,a} + p_{19,b} = p_{1,a} + p_{1,b}\end{dmath}

Can I get breqn to stop treating =, < and \leq as special symbols? Can I get it to treat \myvee like a = instead` If not, what other options are there?

I tried the compact option of breqn, but that still prefers = etc. to other breaking points, and, additionally, it makes the formula overlap with its own tag (i.e. the number I specify), which is unacceptable.

I don't mind inserting ‘you may break the line here’ marks, but I'd like to avoid inserting ‘hard’ breaks manually because I have a lot of these formulas.

breqn will break at all non hidden relation symbols.

\documentclass{article}
\usepackage{breqn}

\DeclareFlexSymbol{\mywedge}{Rel}{bin}{5E}
\DeclareFlexSymbol{\myvee}{Rel}{bin}{5F}

\begin{document}

\begin{dmath}[number={$S_{1,19}$}]
p_{19,a} \hiderel{<} p_{1,a}
\myvee
p_{19,a} + p_{19,b} \hiderel{<} p_{1,a} + p_{1,b}
\myvee
p_{19,a} \hiderel{=} p_{1,a} \hiderel{\mywedge} p_{19,a} + p_{19,b} \hiderel{=} p_{1,a} + p_{1,b}
\end{dmath}

\end{document}

• Thanks, that was pretty much exactly what I was looking for! However, do you have any idea how I could get breqn to not align the \myvees in the next line, but just indent by a fixed amount? Apr 21, 2016 at 10:13
• @ManuelEberl I don't know; I find breqn more difficult to manage than manual breaking Apr 21, 2016 at 10:26