# Xy-pic User's Guide

Kristoffer H. Rose <kris@diku.dk>

This document is a hypertext version of a document obtainable in several printable formats through the Xy-pic home page. It was generated using LaTeX2HTML.

### Abstract:

Xy-pic is a package for typesetting graphs and diagrams using Knuth's TeX typesetting system. Xy-pic works with most of the many formats available, e.g., plain TeX, LaTeX, and AMS-TeX. Several styles of input for various diagram types are supported; they all share a mnemonic notation based on the logical composition of visual components. This guide concentrates on how to typeset matrix-like' diagrams, such as commutative diagrams, in the following style:

was typeset by the Xy-pic input lines

\xymatrix{
U \ar@/_/[ddr]_y \ar@/^/[drr]^x
\ar@{.>}[dr]|-{(x,y)}            \\
& X \times_Z Y \ar[d]^q \ar[r]_p
& X \ar[d]_f       \\
& Y \ar[r]^g   & Z                }

Such diagrams have the following characteristics:
• Specified as a matrix of entries that are automatically aligned in rows and columns.
• Any entry may be connected to any other entry using a variety of arrow styles all rotated and stretched as required.
• Arrows may be decorated with labels that are tied to a specified point along the arrow and extend in a particular direction; and arrows may be paired, cross, and visit/bend around other entries on the way'.
Several other styles of input are supported; a short survey of the possibilities is included last at the end along with information on how Xy-pic can be obtained.