# How can I draw this commutative diagram?

Here is the diagram I want to draw: Any

• Try with tikz-cd. Feb 2 at 14:14
• @Zarko could you tell me some more details please? Feb 2 at 14:24

Just sit down and read the manual of tikz-cd:

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

\begin{document}

$\begin{tikzcd}[row sep=huge] H_{\bullet}(\Sigma X) \arrow[r,"c_*"] \arrow[dr,bend right,"\Delta"'] & H_{\bullet}(\Sigma X\vee\Sigma X) \arrow[r,"(f\vee g)_*"] \arrow[d,shift right=0.5em,"j?"'] & H_{\bullet}(Y) \\ & H_{\bullet}(\Sigma X)\oplus H_{\bullet}(\Sigma X) \arrow[u,shift right=0.5em,"i_{1*}\oplus i_{2*}"'] \arrow[ur,bend right,"f_*\oplus g_*"'] \end{tikzcd}$

\end{document} Let's examine one of the arrows

\arrow[dr,bend right,"\Delta"']


We want it to go down and right, with a bend to the right (the logic about the direction is not immediate), with a label \Delta on the right side of the arrow (denoted by the prime).

Right and left are determined like for rivers: imagine to be at the source and to be looking towards the end.