# Bold arrows in xymatrix

How can I produce a bold arrow in the package \xymatrix? I've tried with \ar@{\bf{->}}[r] and similar alternatives without success.

-
If you use dvips you could use something like \ar@[|(3)]. More info in the pages 27 and 28 of the XY-pic Reference Manual. – Manuel Dec 9 '12 at 22:14
\xymatrix{A \ar@*{[|(3)]}[r] & B} with pdflatex warns that varying the arrow thickness is not implemented. :( – egreg Dec 9 '12 at 23:20
Thanks, I'm using pdflatex, so I would very much appreciate a solution that works there. I'll add the tag. – user17786 Dec 10 '12 at 14:57
@user17786 I'm afraid that you can't receive any better answer than "it's not implemented". Try contacting the maintainers. – egreg Feb 2 '13 at 22:32

If you try compiling this document with pdflatex

\documentclass{article}
\usepackage[all]{xypic}
\begin{document}
\xymatrix{A \ar@*{[|(3)]}[r] & B}
\end{document}


<xymatrix 2x1

Xy-pic Warning: The linewidth 1.19994pt effect is not implemented
with the current driver. [notimpl:4].

Xy-pic Warning: The linewidth 1.19994pt effect is not implemented
with the current driver. [notimpl:4].

Xy-pic Warning: The linewidth 1.19994pt effect is not implemented
with the current driver. [notimpl:4].

44>


This means that the feature is not available with the current implementation of the xypdf driver (version 1.7)

-

This might be considered 'bad latex', but i've made some arrows bold by just putting in a few on top of each other.

\xymatrix{ & A \ar[dl] \ar[dr] & \ B \ar[rr] \ar[rr] \ar[rr] \ar[rr] & & C}

gives

sorry if that isn't the most helpful but at least works as a temporary solution/last resort.

-

This is very easy! Repeat the arrow once with displacement @<0.2mm> and once with @<-0.2mm> or with whatever displacement you find pretty and with as many repetitions of various displacements as you like.

-