[Xy-pic] Bug report

[Ross Moore]

Hi Vadim,

On 09/02/2007, at 1:57 AM, Vadim Yu. Radionov wrote:

> Hello,
>
> I wonder if it is not a bug that compiling
>
> \documentclass{amsart}
> \usepackage[curve,matrix,arrow]{xy}
> \begin{document}
> $\xymatrix{Y \ar@/_1pc/[r]_g & X}$
> \end{document}
>
> works fine but changing X to lower case redirects the arrow head.

Yes.
There seems to be a subtle bug in the curve coding, with
regard to the direction at the end of an arrow.

It doesn't happen always.
The easiest work-around is to twiddle the numbers a bit;
e.g.,

    $\xymatrix{Y \ar@/_1.07pc/[r]_g & x}$

works fine.

>
> (My matrix was more complex, this is just a sample.
> \vphantom X or @1 for one-line matrix helps.)
>
> I'm using XY 3.7 with teTeX-2.0.2_2
>
> Sincerely yours,
>
> Vadim


Thanks for the report.
Tracking this down probably requires a lot of hard tracing work.
It is not likely to be fixed anytime soon.


Hope this helps,

	Ross

------------------------------------------------------------------------
Ross Moore                                         ross at maths.mq.edu.au
Mathematics Department                             office: E7A-419
Macquarie University                               tel: +61 +2 9850 8955
Sydney, Australia  2109                            fax: +61 +2 9850 8114
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