Ich würde `\mathstrut` in die *nodes* der Matrix einfügen. Das führt IHMO zu einer saubereren vertikalen Ausrichtung: \documentclass[varwidth, margin=5mm]{standalone} \usepackage[ngerman]{babel} \usepackage{amsmath, relsize, tikz} \usetikzlibrary{matrix, fit, positioning} \begin{document} \begin{tikzpicture}[ font=\footnotesize, rounded corners=0.125pt, ] % Einträge der Matrix \def\a{\mathlarger{\mathlarger{\boldsymbol{\ast}}}} \def\b{{\bullet}} % Matrix \matrix (m) [ matrix of math nodes, inner sep=0pt, column sep=0.25em, row sep=1pt, nodes={font=\mathstrut,text width=1em,align=center}, ] {% |(oL)|\a & \b & \b & \cdots & |(oM)|\b & |(T1o)|\b & \cdots & |(T2o)|\b & |(oR)|\b \\ 0 & |(d22)|\a & \b & \cdots & \b & \b & \cdots & \b & \b \\ 0 & 0 & |(d33)|\ddots & \ddots & \vdots & \vdots & \cdots & \vdots &\vdots \\ \vdots & \vdots & \ddots & |(d44)|\ddots & \b & \b & \cdots & \b &\b \\ 0 & 0 & \cdots & 0 & |(uM)|\a & |(T1u)|\b & \cdots & |(T2u)|\b &\b \\ };% % Treppe % oben \draw[] (oL.north west) -- (oL.south west) -- (oL.south west-|d22.north west) -- (d22.south west) -- (d22.south east) -- (d22.south east-|d33.north west) -- ([yshift=1.5em]d33.south west); % unten \draw[] ([xshift=0.5em]d44.south) -- (d44.south-|uM.north west) -- (uM.south west) -- (uM.south east); % Rahmen \draw[red] (uM.south east) -- (oM.north east) -- (oM.north east-|oL.north west) node[midway, above, font=\tiny\sffamily]{Stufenform}; \end{tikzpicture} \end{document} ![alt text][1] Wird einem die Matrix dadurch zu groß, kann man den Abstand der Zeilen beispielsweise mit `row sep=0pt` verkleinern. [1]: http://texwelt.de/wissen/upfiles/test_20170422_192052.png

Ich würde `\mathstrut` in die *nodes* der Matrix einfügen. Das führt IHMO zu einer saubereren vertikalen Ausrichtung: \documentclass[varwidth, margin=5mm]{standalone} \usepackage[ngerman]{babel} \usepackage{amsmath, relsize, tikz} \usetikzlibrary{matrix, fit, positioning} \begin{document} \begin{tikzpicture}[ font=\footnotesize, rounded corners=0.125pt, ] % Einträge der Matrix \def\a{\mathlarger{\mathlarger{\boldsymbol{\ast}}}} \def\b{{\bullet}} % Matrix \matrix (m) [ matrix of math nodes, inner sep=0pt, column sep=0.25em, row sep=1pt, nodes={font=\mathstrut,text width=1em,align=center}, ] {% |(oL)|\a & \b & \b & \cdots & |(oM)|\b & |(T1o)|\b & \cdots & |(T2o)|\b & |(oR)|\b \\ 0 & |(d22)|\a & \b & \cdots & \b & \b & \cdots & \b & \b \\ 0 & 0 & |(d33)|\ddots & \ddots & \vdots & \vdots & \cdots & \vdots &\vdots \\ \vdots & \vdots & \ddots & |(d44)|\ddots & \b & \b & \cdots & \b &\b \\ 0 & 0 & \cdots & 0 & |(uM)|\a & |(T1u)|\b & \cdots & |(T2u)|\b &\b \\ };% % Treppe % oben \draw[] (oL.north west) -- (oL.south west) -- (oL.south west-|d22.north west) -- (d22.south west) -- (d22.south east) -- (d22.south east-|d33.north west) -- ([yshift=1.5em]d33.south west); % unten \draw[] ([xshift=0.5em]d44.south) -- (d44.south-|uM.north west) -- (uM.south west) -- (uM.south east); % Rahmen \draw[red] (uM.south east) -- (oM.north east) -- (oM.north east-|oL.north west) node[midway, above, font=\tiny\sffamily]{Stufenform}; \end{tikzpicture} \end{document} ![alt text][1] [1]: http://texwelt.de/wissen/upfiles/test_20170422_192052.png