%% %% Ein Beispiel der DANTE-Edition %% Mathematiksatz mit LaTeX %% 2. Auflage %% %% Beispiel 10-10-5 auf Seite 240. %% %% Copyright (C) 2012 Herbert Voss %% %% It may be distributed and/or modified under the conditions %% of the LaTeX Project Public License, either version 1.3 %% of this license or (at your option) any later version. %% %% See http://www.latex-project.org/lppl.txt for details. %% %% %% ==== % Show page(s) 1 %% %% \documentclass[]{exaarticle} \pagestyle{empty} \setlength\textwidth{352.81416pt} \AtBeginDocument{\setlength\parindent{0pt}} \StartShownPreambleCommands \usepackage{amsmath,amssymb} \makeatletter \def\underbraceMatrix{\@ifnextchar[{\underbraceM@i}{\underbraceM@i[4pt]}} \def\underbraceM@i[#1]#2{\underbraceM@ii{#2}{#1}}% \def\underbraceM@ii#1#2{\mathop{\vtop{\m@th\ialign{##\crcr $\hfil\displaystyle{#1}\hfil$\crcr \noalign{\kern3\p@\nointerlineskip}% \kern#2\upbracefill\kern#2\crcr\noalign{\kern3\p@}}}}\limits} \makeatother \StopShownPreambleCommands \begin{document} $\underbrace{% \left(\begin{array}{cc} A_{\cal E E} & A_{\cal E I}\\ A_{\cal I E} & A_{\cal I I} \end{array}\right)}_{\textstyle=A} % \underbraceMatrix{% \left(\begin{array}{cc} A_{\cal E E} & A_{\cal E I}\\ A_{\cal I E} & A_{\cal I I} \end{array}\right)}_{\textstyle=A} % \underbraceMatrix[1em]{% \left(\begin{array}{cc} A_{\cal E E} & A_{\cal E I}\\ A_{\cal I E} & A_{\cal I I} \end{array}\right)}_{\textstyle=A}$ \end{document}