I'm interested in making a type diagram:

enter image description here

I have the following commands:

\A \ar[r]^-{f} \ar[d]_-{g} & B \\
\C \ar[ur]_-{h}}    

Who provided me with: enter image description here

What should I change to do the first diagram?


  • 4
    Hint: you need 3 columns, 2 rows. C should be in the 2nd row, 2nd column. Then, change the arrow directions accordingly. – Sigur Nov 16 '18 at 17:53
  • 1
    Why not use tikz-cd? – murray Nov 16 '18 at 20:39

Welcome to TeX.SE! If you are not insisting on xymatrix, you could try

\begin{tikzcd}[row sep=4em]
A \arrow[rr, "f"] \arrow[rd, "g"swap]& & B\\
& C \arrow[ur, "h"swap] &

enter image description here

EDIT: switched to relativistic ;-) units, big thanks to @egreg.

  • I'm not a fan of absolute length such as 1.2cm, for these cases. – egreg Nov 16 '18 at 18:29
  • 1
    @egreg Morally I agree but do you really want to add an empty line instead? – user121799 Nov 16 '18 at 18:30
  • 2
    I suggest using relative units such as em or ex. – egreg Nov 16 '18 at 21:06
  • Sorry for the basic question, but isn't the relative unit convertible to cm for example in the end? – Diaa Nov 18 '18 at 6:00

Using the xymatrix package you can see an example of little guide for this package: https://www.jmilne.org/not/Mxymatrix.pdf. I have created with this package, for your request, a simple code.

Picture with equilateral triangle.

enter image description here

\ar@{->}[rr]^f \ar@{->}[rd]_g & & B \ar@{<-}[ld]^h\\
  • 1
    It is not necessary to use @{->} since it is the standard arrow style. – Sigur Nov 17 '18 at 21:00
  • 1
    Why empty 3rd line in the second example? – Sigur Nov 17 '18 at 21:01
  • 1
    Although it is not wrong, it is not so natural to insert an arrow from B to C with reversed tip at the starting point. It is easier to read the code if the arrow starts from C. – Sigur Nov 17 '18 at 21:11
  • I've done a lot of rehearsals reading the guide. And to have an equilateral triangle with no errors in the compilation I have inserted the third empty line and I must necessarily use @{->}. I have tried to do my best, I can assure you. – Sebastiano Nov 17 '18 at 21:11
  • 2
    I don't know the difference between @C and @C-. Also, if you use column distance equal to half centimeter, you have to be sure that the diagonal arrows also have such length. There is @R also. – Sigur Nov 17 '18 at 21:16

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.