Xy-pic User's Guide

2.4 Sliding arrows sideways

It is often desirable to have several parallel arrows between two objects. This can be done by sliding either or both arrows sideways a distance given as a TeX dimension enclosed in @<>s: it specifies how far "sideways" the arrow should be moved, e.g.,

\xymatrix{
 A \ar@<1ex>[dr]^a_{.} \\
   & B \ar@<1ex>[ul]^b \ar@<1ex>[r]^c
     & C \ar@<1ex>[l]^d_{.} }

will typeset

A positive distance will slide the arrow in the "^-direction," e.g., the two arrows above are slid in the direction of the labels a, b, c, and d, respectively; a negative distance in the "_-direction." The distance <@1ex> is often appropriate since it corresponds roughly to the height of letters like "x," in the type size being used.

 

Exercise 10.

Typeset  .

Answer.

 

Xy-pic User's Guide