Commutative diagram: get an arrow to 'skip' an object

Question

    $$\begin{tikzcd} A\ar[r,shift left,"f"] 
&\ar[l,shift left,"h"] B\ar[r,shift left,"g"] 
&\ar[l,shift left,"l"]\ar[l,bend left, shift left,"h"] 
C\end{tikzcd}$$

This is almost as I'd like it to be, except that the $h$ arrow is going from $C$ to $B$ rather than from $C$ to $A$. How can I modify the code so it does that?

EDIT: accidentally called two arrows 'h'. This was not intentional, but I think the text makes it clear which one I'm referring to.

score 4 · Accepted Answer · 2015-10-18T12:08:22.190

4

Use ll in \ar[ll,bend left, shift left,"h"]. Two ls mean that the arrow should go two positions to the left.

\documentclass{article}
\usepackage{tikz-cd}

\begin{document}
      \[\begin{tikzcd} A\ar[r,shift left,"f"]
            &\ar[l,shift left,"h"] B\ar[r,shift left,"g"]
            &\ar[l,shift left,"l"]\ar[ll,bend left, shift left,"h"] C
        \end{tikzcd}
      \]
\end{document}

edited Oct 18 '15 at 12:08

answered Oct 18 '15 at 12:01

And in LaTeX, don't use $$...$$, use \[...\] as the saying goes.... – Oct 18 '15 at 12:09
That's for the answer. But what's the advantage of [ \backslash [...\backslash ]]? – man_in_green_shirt Oct 18 '15 at 12:25
@man_in_green_shirt: Please see: Why is \[ ... \] preferable to $$ ... $$? – Oct 18 '15 at 12:31
Had never heard of that. Thanks, will be sure to use it in the future! – man_in_green_shirt Oct 18 '15 at 12:35
What if I'm just writing the name of a function? Say I want to refer to the function $f$. Is it ok to write f between two dollar signs, or is there a preferable way to do it? – man_in_green_shirt Oct 18 '15 at 13:38
1

@man_in_green_shirt $ are plain TeX primitives. $f$ will be $f$ in LaTeX and $$f$$ will be \[f\]. However, $f$ is more widely used and doesn't have much drawbaacks as its $$ cousin. – Oct 18 '15 at 13:48

Commutative diagram: get an arrow to 'skip' an object

1 Answers1