Xy-pic User's Guide

2.7 Arrows passing under

Arrows can pass under (or via) any other entry: Just insert 't, i.e., a quote (apostrophe) character followed by a target, for each entry that should be visited except the last, "ordinary & final" entry:

\xymatrix{
 {\circ}
  \ar@{|-->} '[dr] ^a
             '[rr]+D*{\bullet} ^b
              [drrr] ^c
         & {\circ} & {\circ} & {\circ} \\
 {\circ} & {\circ} & {\circ} & {\circ} }

typesets

As you see, labels are set separately on each segment.

 

Exercise 12.

Typeset the "lambda cube"

Hint: "going under" an empty entry leaves a small gap at that location. The compactness is achieved using a trick described in section 3.3.

Answer.

 

Xy-pic User's Guide