Blank or no arrow in a commutative diagram

Question

I learned from this nice post that a commutative diagram with the CD environment can have arrows pointing and their commands:

right
```
@>>>
```
left
```
@<<<
```
down
```
@VVV
```
up
```
@AAA
```

Question: what is the case that if I just like to keep a blank spacing without arrow? What is the command?

May I suggest that you use the packages xypic or tikz-cd for drawing commutative diagrams? They have somewhat intuitive syntax... But, I will post an answer too... :-) — kan, May 27 '14 at 17:33
Thanks kan, a similar but not the same issue , but with MWE. See the new post — wonderich, May 27 '14 at 17:39
You don't have to excuse yourself. Just post some compilable code next time; that's all. — Svend Tveskæg, May 27 '14 at 18:07

score 2 · Accepted Answer · edited Oct 10 '14 at 06:10

The example is taken verbatim from Milne's notes on amscd package:

Here is the MWE showing all the possible arrows in the amscd package:

\documentclass{amsart}
\usepackage{amscd}
\begin{document}
$\begin{CD}
A @<<< B @>>> C\\
@. @| @AAA\\
@. D @= E
\end{CD}$
\end{document}

The output:

In particular, the complete list of arrows is:

right
```
@>>>
```
left
```
@<<<
```
down
```
@VVV
```
up
```
@AAA
```
horizontal equals to
```
@=
```
vertical equals to
```
@|
```
empty arrow
```
@.
```

PS: You'd probably appreciate my comment under your question post if that is coming from someone with more experience, so please see Milne's Guide to Commutative Diagram Packages for some words about his personal experience.

I see, Kan, thanks, it is pretty clear! +1. – wonderich May 27 '14 at 18:23 — wonderich, May 27 '14 at 18:23

Blank or no arrow in a commutative diagram

1 Answers1

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