# How to create a grid with a single letter in each cell and numbers on top to correspond to position?

0   1   2   3
R   R   R   R
*¯¯¯*¯¯¯*¯¯¯*
* a | b | c |
*___*___*___*
L   L   L   L


I would like to create a grid similar to the one above, it would be a grid with a single letter per cell and at each cell divider it would have R on the top and L on the bottom, and in addition to this numbers, starting at 0, at each cell divider; as shown above.

The * and ¯¯ characters are just for illustration purposes, and I would prefer an actual grid pattern.

• Welcome to TeX SX! What exactly do you call a cell divider? – Bernard Jan 1 '16 at 15:09
• So you want the R on top of the vertical lines? Not sure if that's possible with a regular tabular. – Alenanno Jan 1 '16 at 15:29

Without a bit more information about what the formatting is about, here's something slightly less than a brute force approach:

\documentclass{article}
\usepackage{tikz}

\begin{document}

\begin{tikzpicture}

\matrix [column sep=0pt,every node/.style={draw,inner sep=1.5ex,text depth=0.5ex,text height=1.5ex,anchor=base}]
{
\node(m0) {a}; & \node(m1) {b}; & \node(m2) {c}; \\
};

\foreach \myletter [count=\x from=0] in {0,1,2,3}
{
\ifnum\x<3\relax
\node[anchor=south] (R\x)  at (m\x.north west) {R};
\node[anchor=north] (L\x)  at (m\x.south west) {L};
\else
\node[anchor=south] (R\x)  at (m2.north east) {R};
\node[anchor=north] (L\x)  at (m2.south east) {L};
\fi
\node[anchor=south]   at (R\x.north) {\x};
}

\end{tikzpicture}

\end{document}


• Thanks, that's what I was looking for. Any way to increase the size of the letters within the cells? – Khalid Jan 1 '16 at 18:37
• @Khalid Inside of every node style, add font= and then add something among: \large, \Large, \LARGE, etc. – Alenanno Jan 3 '16 at 22:45

This is a simple solution with the blkarray package: I use the fact that different blocks, within a blockarray environment, can have different column separators:

\documentclass{article}

\usepackage{blkarray}
\usepackage{geometry}
\newcounter{col}
\usepackage{xcolor}
\usepackage{stackengine}
\setstackEOL{\\}
\usepackage{pst-node}
\usepackage{auto-pst-pdf}
\usepackage{dashrule}
\begin{document}

\centering
\setcounter{col}{0}
\begin{blockarray}{*{3}{c}}
\begin{block}{@{\makebox[0pt]{\thecol}\stepcounter{col}}*{3}{c@{\makebox[0pt]{\thecol}\stepcounter{col}}}}
& & \\
\end{block}
\begin{block}{@{\makebox[0pt]{R}}*{3}{c@{\makebox[0pt]{R}}}}
& & \\[-1.5ex]
\end{block}
\begin{block}{@{\makebox[0pt]{\tiny\textbullet}}*{3}{>{\vardashfill}c@{\makebox[0pt]{\tiny\textbullet}}}}
& & \\[-0.5ex]
\end{block}
\begin{block}{@{\hskip\tabcolsep}*{3}{>{\Large}c|}}
a & b & c \\[-1.2ex]
\end{block}
\begin{block}{@{\makebox[0pt]{\tiny\textbullet}}*{3}{ >{\vardashfill}c@{\makebox[0pt]{\tiny\textbullet}}}}
& & \\[-0.5ex]
\end{block}
\begin{block}{@{\makebox[0pt]{L}}*{3}{c@{\makebox[0pt]{L}}}}
& & \\
\end{block}
\end{blockarray}

\end{document}