[Tex/LaTex] Drawing a particular commutative diagram

beamercommutative-diagramsdiagrams

I can draw

using

\begin{diagram}
X &\rTo^{\gamma} &Y & \lDotsto & \varepsilon_2\\
\dTo^\alpha  &\ruTo^\beta & & &\\
Z& \lDotsto &\varepsilon_3
\end{diagram}

and the following declarations in the preample

\documentclass{beamer}
\usepackage[small,nohug,heads=littlevee]{diagrams}
\diagramstyle[labelstyle=\scriptstyle]

Can someone please show me how to modify things to obtain the following variant of the original diagram?

Thank you very much!

Best Answer

If you don't mind using xy-pic, the code

\documentclass{beamer}
\usepackage[all,cmtip]{xy}
\begin{document}
\begin{displaymath}
  \xymatrix{
    {X} \ar[rr]^{\gamma} \ar[dr]^{\alpha}
    && {Y}\\
    {\varepsilon_{3}} \ar[r]
    & {Z} \ar[ur]^{\beta}
    & {\varepsilon_{2}} \ar[u]
  }% xymatrix
\end{displaymath}

\end{document}

will produce

For a tutorial on commutative diagrams using xy-pic, see section 8 of "Getting up and running with AMS-LaTeX", at https://www.ctan.org/tex-archive/info/amslatex-primer?lang=en

Related Solutions

[Tex/LaTex] Drawing commutative diagram in tex

You may want to learn tikz-cd:

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

\begin{document}
\[
\begin{tikzcd}[row sep=2.5em]
A' \arrow[rr,"f'"] \arrow[dr,swap,"a"] \arrow[dd,swap,"g'"] &&
  B' \arrow[dd,swap,"h'" near start] \arrow[dr,"b"] \\
& A \arrow[rr,crossing over,"f" near start] &&
  B \arrow[dd,"h"] \\
C' \arrow[rr,"k'" near end] \arrow[dr,swap,"c"] && D' \arrow[dr,swap,"d"] \\
& C \arrow[rr,"k"] \arrow[uu,<-,crossing over,"g" near end]&& D
\end{tikzcd}
\]
\end{document}

The only trick is to draw the "g" arrow later (and in the opposite direction), so that it can properly cross over the "k'" arrow that would be drawn later if the "g" arrow started from "A" instead of "C".

enter image description here

[Tex/LaTex] Drawing non-trivial commutative diagrams

This would be definitely doable in TikZ or PSTricks, but I think it'd be an overkill for a simple diagram as this. I think you should use tikz-cd, very minimal code, and specifically designed for this kind of diagrams.

Keep in mind that it works like a matrix (a table basically), so you know how you can place the various "nodes". Also, the command for the arrows are easy too, the letters indicate the direction: u for up, d for down, r and l for right and left, dr for down-right, drr for down-right-right, and so on.

I couldn't read the text on some of the arrows, so you might have to fix that, but it gives the idea.

Output

output

Code

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

\begin{document}
\[\begin{tikzcd}
        & & T(TM) & & T^*(TM)\\
        & & T^{*}M \arrow[u, "X_H", swap] \arrow[urr, "\delta_H", swap]\\
   R    \arrow[uurr, "X_{H}\circ(X\circ\varphi)", bend left=45]  
        \arrow[urr, "\alpha\circ\varphi", swap, bend left] 
        \arrow[rr] 
        \arrow[drr, "X\circ\varphi", bend right]  
        \arrow[ddrr, "X_{L}\circ(X\circ\varphi)", swap, bend right=45] 
        & & M \arrow[u, "\alpha", swap] \arrow[d, "X"] \\
        & & TM \arrow[d, "X_L"] \arrow[drr, "\delta_L"]\\
        & & T(TM) & & T^*(TM)
\end{tikzcd}\]
\end{document}