[closed] pgfplot: matrix plot Layout anpassen

%\documentclass[]{article}
\documentclass[border=3pt, varwidth]{standalone}
\usepackage{pgfplots}
 \pgfplotsset{width=7cm,compat=1.13}
\begin{document}

% pgfplots.pdf, S. 115
\pgfplotsset{ZahlenAnzeigen/.style={
%TextFarben, 
nodes near coords*={ 
\pgfmathsetmacro{\Nenner}{int(\nenner)}
\ifnum\Nenner=1
    $\textcolor{red}{\pgfmathprintnumber[precision=0]\zaehler}$%
\else
    ${\frac{\pgfmathprintnumber[precision=0]\zaehler}
    {\pgfmathprintnumber[precision=0]\nenner}}$%
\fi},
every node near coord/.append style={xshift=0pt,yshift=-7pt,  font=\footnotesize}
}}

\tikzset{TextFarben/.style={
r/.style={red},  b/.style={blue}, s/.style={black}
}}

\tikzset{HintergrundFarben/.style={
R/.style={red!50},  B/.style={blue!50}, S/.style={black!50}
}}

\begin{tikzpicture}
\begin{axis}[enlargelimits=0.2]
\addplot[matrix plot,
%mark=*,
only marks,  % ohne das geht es nicht
%point meta=\thisrow{color},
ZahlenAnzeigen,
visualization depends on={\thisrow{Z}  \as \zaehler},
visualization depends on={\thisrow{N}  \as \nenner},
]
table[]  {
x y   Z N color bgcolor
1 1   1 4 b       B
1 2   2 3 s       S
2 1   3 2 b      B
2 2   4 1 r       R
};
\end{axis}
\end{tikzpicture}

\end{document}