How to write over a double-ended arrow

Question

I've come across how to write over a left or right facing arrow but not one that's double-ended. I tried this below (but with \ in front of both [ and ] but for some reason this won't typeset here) but it doesn't work so any help would be greatly appreciated!

\[ a \xleftrightarrow{\text{x}} b \]

Many thanks!

I've tried removing the x after the backslash however this just means the other x isn't above the arrows, simply next to it. — Janitt, Mar 04 '19 at 11:34
Welcome to TeX.SX! Please help us help you by providing a minimal compilable code example (MWE) illustrating the issue. — TeXnician, Mar 04 '19 at 11:40
You can look at the answer to this question, which defines precisely such a command. — Bernard, Mar 04 '19 at 11:56

Raaja_is_at_topanswers.xyz · Accepted Answer · 2019-03-04T11:42:37.733

3

You mean something like this:

\documentclass{article}
\usepackage{amssymb}
\usepackage{stackengine}
%https://tex.stackexchange.com/questions/123219/writing-above-and-below-a-symbol-simultaneously
\newcommand\stackleftrightarrow[1]{%
    \mathrel{{\stackon[4pt]{$\leftrightarrow$}{$\scriptscriptstyle#1$}}}}
\begin{document}
    $   a \stackleftrightarrow{x} b$
\end{document}

to get:

A more generalised approach would be to:

\documentclass{article}
\usepackage{amsmath,amssymb}



\newcommand{\xrightarrowdbl}[2][]{%
    \leftarrow\mathrel{\mkern-14mu}\xrightarrow[#1]{#2}
}
%https://tex.stackexchange.com/questions/260554/two-headed-version-of-xrightarrow
\begin{document}
    $x \xrightarrowdbl{\text{a}} y$\\
    $x \xrightarrowdbl{\text{your text}} y$
\end{document}

to get:

edited Mar 04 '19 at 11:42

answered Mar 04 '19 at 11:36

Raaja_is_at_topanswers.xyz

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That's exactly what I'm looking for, thank you! I'll give that a go when I can access my work again later tonight:) – Janitt Mar 04 '19 at 15:48
@Janitt you are welcome, if you find the answer useful, consider accepting it. – Raaja_is_at_topanswers.xyz Mar 04 '19 at 16:29

How to write over a double-ended arrow

1 Answers1