[Tex/LaTex] How to write N x N (with a multiplication symbol, for matrix dimensions)

math-modesymbols

I need to write something like NxN in LaTeX but I do not get how… How to do such thing?

The x is done by \times. It must be used in mathmode:

$3\times4$

$N\times N$

Saying \limits does not increase the size of the summation symbol, it just moves the limits.

\documentclass{article}
\usepackage{amsmath}
\begin{document}
$\sum\limits_{i=1}^n$ \quad $\sum_{i=1}^n$ \quad
\end{document}

If you want to do the same with the \natural symbol you need to use \mathop.

$\natural_{i=1}^n$ \quad $\mathop\natural\limits_{i-1}^n$

If you actually want a larger \natural you can create one with \large, \Large, etc.

\[ \mathop{\hbox{\Large$\natural$}}\limits_{i=1}^n \natural \]

You could also use \scalebox from the graphicx package.

This example works as expected: (note the r in front of the title string)

#!/usr/bin/env python

import matplotlib.pyplot as plt

plt.title(r'$A \times B$')
plt.plot([0,1,2])
plt.savefig('test.png')