[Xy-pic] loops of different sizes?

[Richard Lewis]

Jürgen Koslowski <koslowj at iti.cs.tu-bs.de> writes:

> Hello,
>
> Here is a little problem that has been bugging me for quite a while, but
> never enough to do something about it.
>
> When drawing loops with the construct \ar@(ul,ur)^a"A";"A", I can
> influence the shape of the loop by varying the arguments in
> parenthesis, but I cannot seem to modify the size of the loop.
> Sometimes, \eg, when drawing automata with circled states, the loops are
> too small.  And now I wish to draw several loops of growing size based at
> the same vertex.  In order to enlarge individual loops I have already used
> auxiliary points, but for several loops this becomes very inconvenient.
>
> Any ideas?

\newgraphescape{L}#1#2{[]!{"#1"*+{}!DL="#1s"}
                       []!{"#2"*+{}!DR="#2t"}
                       "#1s" :@(dl,dr) "#2t"}
\begin{equation}
  \xygraph{ A  :@(dl,dr)"A"            %innermost loop
           []!{"A"*+{}!DL="s"}
           []!{"A"*+{}!DR="t"}
           "s" :@(dl,dr) "t"           %loop 2
           []!Lst                      %loop 3
           []!L{ss}{tt}
           []!L{sss}{ttt}
           []!L{ssss}{tttt}
         }
\end{equation}

Keep adding s and t's to get more loops