4

I would like to dash the upper arrow in amsfonts' \rightrightarrows. Here is what I had in mind:

1]

I've found this similar post here, but I seem to be unable to even find where amsfonts defines \rightrightarrows. Thanks for any help.

Almacomet
  • 361
  • 1
    This is a little harder than the question you link to because \rightrightarrows is just a single glyph (which is declared in amssymb.sty btw). It is not constructed out of two separate arrows. – Circumscribe Nov 14 '18 at 20:01

1 Answers1

4

You could create this symbol by cutting up and reassembling \rightrightarrows using \clipbox (from trimclip.sty, which is part of adjustbox package). It doesn't seem very elegant, but it works. You can tweak the numbers a little if you want longer or shorter dashes or spaces.

\documentclass{article}

\usepackage{amssymb,trimclip}

\newcommand*\rightdashedrightarrows{\mathpalette\rightdashedrightarrowsaux\relax}
\newcommand*\rightdashedrightarrowsaux[2]{%
  \mathrel{%
    \clipbox*{0pt          {-\depth} {0.20\width} {\height}}  {$#1\rightrightarrows$}%
    \clipbox*{{0.20\width} {-\depth} {0.35\width} {.5\height}}{$#1\rightrightarrows$}%
    \clipbox*{{0.35\width} {-\depth} {0.55\width} {\height}}  {$#1\rightrightarrows$}%
    \clipbox*{{0.55\width} {-\depth} {0.70\width} {.5\height}}{$#1\rightrightarrows$}%
    \clipbox*{{0.70\width} {-\depth} {1.00\width} {\height}}  {$#1\rightrightarrows$}%
  }%
}

\begin{document}

\[
    A \rightdashedrightarrows B_{C\rightdashedrightarrows D_{E \rightdashedrightarrows F}}
\]

\[
    A \rightrightarrows B_{C\rightrightarrows D_{E \rightrightarrows F}}
\]

\end{document}

enter image description here

I'm using \mathpalette to make the symbol also work for different math styles. A simpler version of the definition that won't work in sub- or superscripts would be

\newcommand*\rightdashedrightarrows{%
  \mathrel{%
    \clipbox*{0pt          {-\depth} {0.20\width} {\height}}  {$\rightrightarrows$}%
    \clipbox*{{0.20\width} {-\depth} {0.35\width} {.5\height}}{$\rightrightarrows$}%
    \clipbox*{{0.35\width} {-\depth} {0.55\width} {\height}}  {$\rightrightarrows$}%
    \clipbox*{{0.55\width} {-\depth} {0.70\width} {.5\height}}{$\rightrightarrows$}%
    \clipbox*{{0.70\width} {-\depth} {1.00\width} {\height}}  {$\rightrightarrows$}%
  }%
}
Circumscribe
  • 10,856