# How to define binary operator [closed]

I'd like to declare a new binary operator. is \DeclareMathOperator appropriate, or is it only for unary operators? Is there a better way than \newcommand{foo}[1]{bar}?

## closed as unclear what you're asking by Mensch, user13907, Stefan Pinnow, Maarten Dhondt, Mike RenfroOct 3 '16 at 13:22

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

• \mathbin{...} – egreg Aug 4 '16 at 19:53
• How about showing us (for example with an image) what operator you want to define? Then it is much more easier to help you. – Mensch Aug 4 '16 at 19:54
• amsmath's \DeclareMathOperator is a (fancy!) "wrapper" for the low-level TeX command \mathop. Not knowing anything specific about the binary operator you have in mind, I'd say that it doesn't seem appropriate to use \mathop for your use case. Insteady, as @egreg has already pointed out, I'd use \mathbin somewhere in the argument of the \newcommand that defines the operator. – Mico Aug 4 '16 at 23:24
• To a first approximation, I'd like to define binary operators that expand to \overset{\sigma}{\cdot} and \overset{\sigma}{\odot}; ultimately I'd like to make the superscript an optional parameter so that I could write A {op1} B to omit the superscript and A op1{\sigma} B to get the3 superscript. – shmuel Aug 8 '16 at 17:00