I'm trying to tex a diagram of the following form:

enter image description here

Even more preferred, I'd like to both have labels for the trees (like $\mathcal T$ and $\pi\mathcal T$ in the above picture), and also a label on the solid arrow sticking out from the tree.

Can this be done in xymatrix, or do I have to get the big tikz guns out?


(this specific diagram is from John Steel's article "An outline of inner model theory", by the way)

  • Welcome! So what have you tried so far?
    – cfr
    Apr 15, 2016 at 16:17
  • Thanks @cfr! Right now I've only looked through a bunch of tikz examples at texample.net/tikz/examples, with no luck. I know how to use xymatrix, but for one I have no idea how to set an arrow to have multiple styles (dots and solid in this case). Apr 15, 2016 at 16:34

1 Answer 1


This is an examply with tikz-cd. The code for the half dotted arrow is slightly modified from this answer by Ignasi, also including some additions.


enter image description here




    decoration={show path construction, 
      lineto code={
          \draw[dotted,-] (\tikzinputsegmentfirst) --($(\tikzinputsegmentfirst)!.7!(\tikzinputsegmentlast)$) coordinate (a);,
          \draw[-{Latex}] ($(\tikzinputsegmentfirst)!.7!(\tikzinputsegmentlast)$)--(\tikzinputsegmentlast);
          \draw[-] (\tikzinputsegmentfirst) --++ (10:1.6cm) node[midway, above, font=\footnotesize] {#1};
          \draw[-] (\tikzinputsegmentfirst) --++ (-10:1.6cm);,

N \arrow[rr, triple={$\pi T$}]& & N_{\alpha}\\
M \arrow[u, swap, "\pi"] 
\arrow[rr, triple={$T$}]
& & M_{\alpha} \arrow[u, swap, "\pi_{\alpha}"]\\
  • Sorry for the super delayed answer, but suddenly I didn't have time to play around with tex. But thanks for the great answer! Apr 30, 2016 at 6:43

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.