Make a Vigenère rectangular in LaTeX

Question

I want to make a rectangular 26x26 table where in the first row contains the letters A, B, ..., Z, the second row B, C, ..., Z, A, the third row C, D, ..., Z, A, B, etc.

One (not efficient) way is the following:

\begin{tikzpicture}
  \draw[step=.5cm,gray,thick]
  (-6,-6) grid (6,6);

  \draw (-5.75,5.75) node{A} (-5.25,5.75) node{B} (-4.75,5.75) node{C}  (-4.25,5.75) node{D}  (-3.75,5.75) node{E}  etc; % this is the first row

  \draw (-5.75,5.25) node{B} (-5.25,5.25) node{C} (-4.75,5.25) node{D}  (-4.25,5.25) node{E}  (-3.75,5.25) node{F}  etc; % this is the second row

  % and so on for the rest rows  
\end{tikzpicture}

Any ideas how to to make this happen more efficiently?

Also what if I want to use the Greek alphabet A, B, Γ, ..., Ω instead of the English alphabet.

Answer 1

Another method:

\documentclass{article}
\usepackage{tikz}

\begin{document}

\begin{tikzpicture}
\foreach \i in {0,...,25} {
  \foreach \j in {0,...,25} {
    \edef\k{\ifnum\numexpr\i+\j\relax>25
        \the\numexpr\i+\j-26\relax
      \else
        \the\numexpr\i+\j\relax
      \fi}
  \node[draw,minimum size=0.5cm,inner sep=0pt]
    at (\i*0.5,-\j*0.5) {\strut\symbol{\numexpr`A+\k\relax}};
  }
  \node at (-0.5,-\i*0.5) {\strut\i};
  \node at (\i*0.5,0.5)   {\strut\i};
}
\end{tikzpicture}
\end{document}

It works as in normal programming language (like C), although integer calculation in TeX is a bit more difficult.

Answer 2

I took the example of the manual:

\documentclass[]{article}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}[scale=0.6,transform shape]
\foreach \x [count=\xi] in {A,...,Z}
\foreach \y [count=\yi] in {\x,...,Z}
\node [draw, top color=white, bottom color=blue!50, minimum size=0.666cm]
at (\xi,-\yi) {$\mathstrut\y$};
\end{tikzpicture}
\end{document}

Egreg pointed out that you need also a lower part:

\documentclass[border=10]{standalone}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}[scale=0.6,transform shape]
\foreach \x [count=\xi] in {A,...,Z}
 {%
   \foreach \y [count=\yi] in {\x,...,Z}
   {
      \node [draw, top color=white, bottom color=blue!50, minimum size=0.666cm]
         at (\xi,-\yi) {$\mathstrut\y$};
     \xdef\Ax{\yi}
   }
  \pgfmathsetmacro\Ax{\Ax+1}
   \foreach \y [count=\yi from \Ax ] in {A,...,\x}
     {
      \ifnum\yi<27
         \node [draw, top color=white, bottom color=blue!50, minimum size=0.666cm]
         at (\xi,-\yi) {$\mathstrut\y$};
       \fi
    }
 }
\end{tikzpicture}
\end{document}

---

As required he a solution with greek letters:

\newcommand\greekletter[1]{%
\ifcase #1 \relax
\or
\alpha\or
\beta\or
\gamma\or
\delta\or
\epsilon\or
\zeta\or
\eta\or
\theta\or
\iota\or
\kappa\or
\lambda\or
\mu\or
\nu\or
\xi\or
\mathrm{o}\or
\pi\or
\rho\or
\sigma\or
\tau\or
\upsilon\or
\phi\or
\chi\or
\psi\or
\omega
\else A
\fi
}

Here the complete MWE:

\documentclass[border=10]{standalone}
\usepackage{tikz}
\newcommand\greekletter[1]{%
\ifcase #1 \relax
\or 
\alpha\or
\beta\or
\gamma\or
\delta\or
\epsilon\or
\zeta\or
\eta\or
\theta\or
\iota\or
\kappa\or
\lambda\or
\mu\or
\nu\or
\xi\or
\mathrm{o}\or
\pi\or
\rho\or
\sigma\or
\tau\or
\upsilon\or
\phi\or
\chi\or
\psi\or
\omega
\else A
\fi
}
\begin{document}
\begin{tikzpicture}[scale=0.6,transform shape]
\foreach \xx [count=\xxi] in {1,...,24}
 {%
   \foreach \yy [count=\yyi] in {\xx,...,24}
   {
      \node [draw, top color=white, bottom color=blue!50, minimum size=0.666cm]
         at (\xxi,-\yyi) {$\mathstrut\expandafter\greekletter{\yy}$};
     \xdef\Ax{\yyi}
   }
  \pgfmathsetmacro\Ax{\Ax+1}
   \foreach \yy [count=\yyi from \Ax ] in {1,...,\xx}
     {
      \ifnum\yyi<27
         \node [draw, top color=white, bottom color=blue!50, minimum size=0.666cm]
         at (\xxi,-\yyi) {$\mathstrut\expandafter\greekletter{\yy}$};
       \fi
    }
 }
\end{tikzpicture}
\end{document}

Answer 3

Here is a variant of Leo's code that can deal with arbitrary alphabets. I'm using fontspec to be able to easily use Greek letters.

% Compile with xelatex or lualatex.
\documentclass{article}
\usepackage{tikz}
\usepackage{fontspec}
\setmainfont{Linux Libertine O}

\def\alphabet{Α,Β,Γ,Δ,Ε,Ζ,Η,Θ,Ι,Κ,Λ,Μ,Ν,Ξ,Ο,Π,Ρ,Σ,Τ,Υ,Φ,Χ,Ψ,Ω}
\def\alphabetlength{24}

\begin{document}
\begin{tikzpicture}
\foreach \row in {1,...,\alphabetlength} {
  \foreach[count=\x] \letter in \alphabet {
    \pgfmathsetmacro\column{Mod(-\row+\x,\alphabetlength)}
    \node[draw,minimum size=0.5cm,inner sep=0pt]
        at (\column*0.5,-\row*0.5) {\strut\letter};
    }
    \node at (-0.5,-\row*0.5) {\strut\row};
    \node at ({\row*0.5-0.5},0)   {\strut\row};
}
\end{tikzpicture}
\end{document}

Answer 4

\documentclass[border=10]{standalone}
\usepackage{tikz}
\begin{document} 
\footnotesize
\begin{tikzpicture}[every node/.style={draw, circle, minimum size=16pt}]
\foreach \x [count=\xi]  in {A,...,Z}
 {\foreach \y [count=\yi] in {\x,...,Z}
   {\node at (6*\xi ex,-6*\yi ex) {\y};}%
  \ifnum\yi>1 \foreach \z [count=\zi from \yi ] in {A,...,\x}
      {\node at (6*\xi ex +6 ex,-6*\zi ex) {\z};}\fi}
\end{tikzpicture}
\end{document}