7

The arrow heads on \twoheadrightarrow don't look like the arrow heads on \rightarrow and \hookrightarrow. Is there some way of fixing this?

For instance, the code

\documentclass{article}
\usepackage{amssymb}

\begin{document}
\[ \hookrightarrow \twoheadrightarrow \rightarrow \]
\end{document}

produces an output as follows.

Arrow heads

Corentin
  • 9,981
chthonian
  • 173

2 Answers2

9

Note that \twoheadrightarrow comes from amssymb package, while the other two are LaTeX predefined.

If you use the package MnSymbol they all are redefined and look the same.

Try the following code

\documentclass{article}
\usepackage{MnSymbol}

\begin{document}
\[ \hookrightarrow \twoheadrightarrow \rightarrow \]
\end{document}

and see whether they are fine (to me, they look better).

enter image description here

If you still need amssymb package for something else, you can load MnSymbol after it:

\usepackage{amssymb}
\usepackage{MnSymbol}
karlkoeller
  • 124,410
6

You could create your own \rrightarrow:

enter image description here

\documentclass{article}
\usepackage{amssymb}% http://ctan.org/pkg/amssymb
\usepackage{mathtools}% http://ctan.org/pkg/mathtools
\newcommand{\rrightarrow}{\mathrel{\mathrlap{\rightarrow}\mkern1mu\rightarrow}}
\begin{document}
\[ \hookrightarrow \twoheadrightarrow \rrightarrow \rightarrow \]
\end{document}

\rrightarrow is an overlay of \rightarrow with a shifted version of itself. The length is 1mu (one math unit) more than \rightarrow, which shouldn't deter too much from using it. You could also play with the kerning a bit, if needed.

Werner
  • 603,163
  • I think it should be possible to "mask" the extra length off somehow. Possibly with some low level TeX box hackery. – kahen May 28 '13 at 05:07
  • 2
    If someone can figure out this "low level TeX box hackery," I'd definitely like to see how its done! – chthonian May 28 '13 at 08:13