Xy-pic User's Guide

## 3.2 Extra entries outside the matrix

It is possible to put extra entries in your diagrams that are not part of any "entry" of the matrix created by `&` and `\\`. This is done with the excursion command

`\save` t `\restore`

where t should be a target in one of the formats described in sections 2.5-2.6. t can do any kind of typesetting desired, for example,

>     \xymatrix{
>      A \ar@{-}[dr]
>      &{}\save[]+<3cm,0cm>*\txt<8pc>{%
>          This is a very big commentary
>          but it does not otherwise affect
>          the diagram.}
>          \ar[l] \ar[d] \restore \\
>      & B \ar@{-}[r] & C \ar@{-}[r] & D
>     }

will typeset

It illustrates how a "down" arrow does not necessarily have to point particularly straight down - in this case because it is based in the displaced pseudo entry.

Xy-pic User's Guide