# What are your options to draw commutative diagrams on MSE? [duplicate]

I know that I asked similar questions in the past, but I still do not seem to figure it out, what the best way is to post a 'complex' diagram on this website.

Nothing seems to work, and the things that do work aquire a lot of work and take to much time in my opinion...

I just posted this question: Universal property of product topology, unique up to homeomorphism

Which was not fun at all. Can you please tell me, how I could have drawn these diagrams here with the most efficient method?

Thank you!

## 1 Answer

$$\underset{\underset{\hspace{-20px}l_k}\searrow}{y\overset{f}\longrightarrow}\underset{\hspace{-20px}X_{l_K}}{\underset{\downarrow P_{r_k}}{\hspace{-20px}X}}$$
I mostly used underset and overset:

\underset{\underset{\hspace{-20px}l_k}\searrow}{y\overset{f}\longrightarrow}\underset{\hspace{-20px}X_{l_K}}{\underset{\downarrow P_{r_k}}{\hspace{-20px}X}}

Might be able to use stackrel after grouping the main line, or getting the arrows longer by requiring an extended arrow package. Could define the triangle with optional arguments to fill in.

• Thank you, but this looks terrible. :) Well... better then my awful hand drawings. – Cornman Aug 20 '19 at 16:45
• it's the ahort arrows below. without using style to rotate them, or extendible arrows, I'm no expert. – Roddy MacPhee Aug 20 '19 at 18:14
• – Roddy MacPhee Sep 13 '19 at 21:45