How to write dimensions below a matrix
Use \underset
, with \scriptscriptstyle
in order to reduce the size.
Note that loading mathpazo
does nothing unless you select suitable font themes.
\documentclass{beamer}
\usefonttheme{serif}
\usefonttheme{professionalfonts}
\usepackage{mathpazo}
\begin{document}
\begin{frame}\frametitle{Write dimensions below matrix}
\[
\begin{bmatrix}
\underset{\scriptscriptstyle n\times n}{A} &
\underset{\scriptscriptstyle n\times n}{B} \\[1.5ex]
C & D
\end{bmatrix}
\]
\end{frame}
\end{document}
Avoid awkward constructions such as \begin{center}$<formula>$\end{center}
: displaymath
is much better, with its shorthand \[...\]
.
with using of the package stackengine
:
\documentclass{beamer}
\usepackage{amssymb}
\usepackage{mathpazo}
%\usepackage{multimedia} not relevant for your problem
%\usepackage{amsfonts} loaded by amssymb
\usepackage{amsmath}
%\setcounter{MaxMatrixCols}{10}
\usepackage{stackengine}
\begin{document}
\begin{frame}
\frametitle{Write dimensions below matrix}
\[\stackMath
\begin{bmatrix}
\stackunder{A}{_{n\times n}} & \stackunder{B}{_{n\times n}} \\[2ex]
C & D
\end{bmatrix}%
\]
\end{frame}
\end{document}
or see, if writing matrix symbol in \mathbf{...}
better emphasize matrices:
\begin{frame}
\frametitle{Write dimensions below matrix}
\[\stackMath
\begin{bmatrix}
\stackunder{\mathbf{A}}{_{n\times n}} & \stackunder{\mathbf{B}}{_{n\times n}} \\[2ex]
C & D
\end{bmatrix}%
\]
\end{frame}
which gives