% \iffalse meta-comment
% rubikrotation.dtx
%
% version 3.0
%
% Authors: RWD Nickalls (dick@nickalls.org)
% and Apostolos Syropoulos (asyropoulos@yahoo.com)
% Copyright 25 September 2015 RWD Nickalls + A Syropoulos
%
% This work may be distributed and/or modified under the
% conditions of the LaTeX Project Public License, either
% version 1.3c of this license or (at your option) any
% later version. The latest version of this licence is in
%
% http://www.latex-project.org/lppl.txt
%
%<*readme>
%
% The rubikrotation package provides a collection of LaTeX commands and macros
% for the typesetting of Rubik cube configurations and rotation
% sequences using the TikZ graphic language.
%
% Please report errors or suggestions for improvement to
%
% Dick Nickalls or Apostolos Syropoulos
%
% This package requires the basic TikZ package to be loaded already
%
%
%<*driver>
\listfiles
\documentclass{ltxdoc}
\IfFileExists{rubikrotation.sty}{\usepackage{rubikrotation}}{%
\GenericWarning{rubikrotation.dtx}{Package file rubikrotation.sty not found.
Documentation will be messed up!^^J
(Generate rubikrotation.sty by (La)TeXing rubikrotation.ins, and then^^J
process rubikrotation.dtx again)^^J}\stop
}%
\usepackage{ifpdf}
\usepackage{url,path} %% for references and paths
\usepackage{graphicx} %% for the two pdf figs
\usepackage{hypdoc} %% for pdf bookmarks + hyperref documenting of packages
%%\OnlyDescription
\EnableCrossrefs
\PageIndex
\CodelineIndex
\CodelineNumbered
\RecordChanges
\setcounter{StandardModuleDepth}{1}
\begin{document}
\DocInput{rubikrotation.dtx}
\PrintChanges
\PrintIndex
\end{document}
%
% \fi
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%
%
%
% \title{The \rubikrotation\ package}
%
% \author{
% RWD Nickalls (dick@nickalls.org) \\
% A Syropoulos (asyropoulos@yahoo.com)
% }
% \date{This file describes version \RRfileversion\ (\RRfiledate)\\
% \texttt{www.ctan.org/pkg/rubik}}
% \maketitle
%
% \begin{abstract}
% The \rubikrotation\ package is a dynamic extension for the
% \textsc{rubikcube} package (both are part of the Rubik `bundle').
% The package provides the \cmd{\RubikRotation} command which
% processes a sequence of Rubik rotation moves on-the-fly (using the Perl script
% \texttt{rubikrotation.pl}), and returns the new Rubik cube state (configuration).
% The \rubikrotation\ package also provides a command for implementing some basic
% checking of the Rubik cube state (\cmd{\CheckRubikState}), and one
% for displaying any errors (\cmd{\ShowRubikErrors}).
%
% The \rubikrotation\ package requires access to the \TeX\ \texttt{write18}
% facility, which is enabled by using the \texttt{--shell-escape} command-line switch.
% The~\rubikrotation\ package has been road-tested on a Microsoft
% platform (with MiKTeX and Strawberry Perl), on a Linux platform
% (Mandriva using {\TeX}Live), and on a Solaris platform (OpenIndiana).
% \end{abstract}
%
% \begin{minipage}{11cm}
% \centering
% \ifpdf
% \includegraphics[width=10cm]{Rubikrot-doc-figD.pdf}
% \else
% \fi
% \end{minipage}
%
% \vspace{-1\baselineskip}
%
% \tableofcontents
%
% \section{Introduction}
%
% The \rubikrotation\ package is a dynamic extension to the \textsc{rubikcube} package.
% It consists of a style option (\texttt{rubikrotation.sty}), a
% Perl script (\texttt{rubikrotation.pl}) and some examples.
%
% The primary role of the \rubikrotation\ package is to implement a sequence of
% Rubik rotation moves on-the-fly using the \cmd{\RubikRotation} command. Consequently, this
% package requires the use of the \texttt{--shell-escape} switch to allow
% command-line control of the Perl script, which is really the `engine' of this package.
%
% The \rubikrotation\ package has been road-tested on a Microsoft
% platform (with MiKTeX and Strawberry Perl\,\footnote{`Strawberry Perl'
% (\texttt{http://strawberryperl.com}) is a free Perl
% environment for MS Windows, designed to be as close as possible to the Perl
% environment of Unix/Linux systems.}), on a Linux platform (Mandriva using
% {\TeX}Live), and on a Solaris platform (OpenIndiana).
%
% The following commands are made available by \texttt{rubikrotation.sty}:
% \begin{quote}
% \begin{verbatim}
% \RubikRotation[]{}
% \SaveRubikState
% \CheckRubikState
% \ShowRubikErrors
%\end{verbatim}
% \end{quote}
%
%
% \section{Requirements}
%
% The \rubikrotation\ package requires the TikZ and the \textsc{rubikcube} packages.
%
%
% \section{Installation}
%
% \subsection{Generating the files}
%
% Place the file \texttt{rubikrotation.zip} into a temporary directory, and unzip it.
% This will generate the following files:
%\begin{quote}
% \begin{verbatim}
% rubikrotation.ins
% rubikrotation.dtx
% rubikrotation.pdf --this document
% rubikrotation.pl --Perl script
% rubikrotationPL.pdf --documentation of rubikrotation.pl
% rubikrotation.1 --the man file
% Rubikrot-doc-figA.pdf
% Rubikrot-doc-figB.pdf
% Rubikrot-doc-figC.pdf
% Rubikrot-doc-figD.pdf
% examples.tex
% examples.pdf
% examples.sh
% examples.bat
%\end{verbatim}
%\end{quote}
% Note that the package includes an `examples' file (\texttt{examples.tex})
% as well as associated \texttt{.sh} (Linux) and \texttt{.bat} (Microsoft) batch
% files which can be used to facilitate processing the file.
% The main package documentation is the file \texttt{rubikrotation.pdf}.
%
% The style option \texttt{rubikrotation.sty} is generated by running (pdf)\LaTeX\ on
% the file \texttt{rubikrotation.ins} as follows:
%\begin{quote}
%\begin{verbatim}
% pdflatex rubikrotation.ins
%\end{verbatim}
%\end{quote}
% The documentation file (\texttt{rubikrotation.pdf}) is then generated using the following
% sequence of steps\,\footnote{Since the documentation includes a complicated indexing
% system as well a \textsc{pdf} index and hyperef links (the package \texttt{hypdoc}
% is used), then a lot of pdflatex runs are required. Prior to the first run it is
% a good idea to delete any relevant \texttt{.toc}, \texttt{.aux}, \texttt{.out} files.}:
%\begin{quote}
% \begin{verbatim}
% pdflatex rubikrotation.dtx
% pdflatex rubikrotation.dtx
% makeindex -s gind.ist rubikrotation
% makeindex -s gglo.ist -o rubikrotation.gls rubikrotation.glo
% pdflatex rubikrotation.dtx
% pdflatex rubikrotation.dtx
%\end{verbatim}
%\end{quote}
%
%
%
% \subsection{Placing the files}
% \label{sec:placingfiles}
%
% Place the files either in a working directory, or where your system
% will find them, e.g.,~in your \texttt{/texmf-local/} directory tree.
% For example, on a Linux platform with a standard \TeX\ Directory Structure (TDS), then:
%
%\medskip
%{\noindent}*.sty $\rightarrow$ \texttt{/usr/local/texlive/texmf-local/tex/latex/rubik/}
%{\newline}*.cfg $\rightarrow$ \texttt{/usr/local/texlive/texmf-local/tex/latex/rubik/}
%{\newline}*.pdf $\rightarrow$ \texttt{/usr/local/texlive/texmf-local/doc/rubik/}
%{\newline}*.pl $\rightarrow$ \texttt{/usr/local/texlive/texmf-local/scripts/rubik/}
%
%\medskip
%{\noindent}\textsc{perl script}:\ \ Make the perl script executable
% (\texttt{chmod +x rubikrotation.pl}), and then
% rename the file as `rubikrotation' (i.e.,~with no file extension), and then place
% the executable script into your current TeXLive binary directory,
% e.g.,~\path!/user/local/texlive/YYYY/bin/i386-linux!.
%
% Sometimes the setting up of a simple one or two-line plain-text
% configuration-file may be useful or even necessary, depending on your system
% (see Section~\ref{sec:configfile} below). Such a file (if one exists) will
% automatically be read by \texttt{rubikrotation.sty} providing the
% file is named \texttt{rubikrotation.cfg}.
%
%\medskip
%{\noindent}\textsc{the `man' file}:\ \ On a Linux platform this file
% (\texttt{rubikrotation.1}) would be typically located in the
% directory \verb!/usr/share/man/man1!.
%
%\medskip
%{\noindent}\textsc{file database}:\ \ Finally, (depending on your system) update the
% \TeX\ file database.
% For example, on a Linux platform this is achieved using the \texttt{texhash} command.
%
%\medskip
%{\noindent}\textsc{quick test}:\ \ To test that your system can now run the perl
% script, just type at the command-line
%\begin{quote}
% \begin{verbatim}
% rubikrotation -h
%\end{verbatim}
%\end{quote}
% which should generate something like the following:
% \begin{verbatim}
% This is rubikrotation version 3.0
% Usage: rubikrotation [-h] -i [-o ]
% where,
% [-h] gives this help listing
% [-i] creates specified input file
% [-o] creates specified output file
% For documentation see: rubikrotation.pdf,
% rubikrotationPL.pdf and rubikcube.pdf
%\end{verbatim}
%
%
% \section{Usage}
% \label{sec:usage}
% Load the packages \texttt{rubikcube.sty}
% and \texttt{rubikrotation.sty} in the \TeX\ file preamble \textit{after} loading
% the TikZ package (both Rubik packages require the TikZ package), for example, as follows:
%\begin{quote}
% \begin{verbatim}
% \usepackage{tikz}
% \usepackage{rubikcube,rubikrotation}
%\end{verbatim}
%\end{quote}
% and run (pdf)\LaTeX\ using the \texttt{--shell-escape} command-line switch
% (see the following section).
%
%
% \subsection{Enabling the \TeX\ `shell' facility}
%
% In order to enable the \TeX\ `write18' facility (so it can run the Perl script)
% it is necessary to invoke (pdf)\LaTeX\ using the \texttt{--shell-escape} switch
% as follows:
%\begin{quote}
% \begin{verbatim}
% pdflatex --shell-escape filename.tex
%\end{verbatim}
%\end{quote}
% In practice, it is probably most convenient to run this command via a
% bash/batch file. For example, on a Linux platform the following bash file
% will run the file, show any errors, and open the \textsc{pdf} using AcrobatReader.
%\begin{quote}
% \begin{verbatim}
% pdflatex --shell-escape filename.tex
% echo "...checking error file"
% grep ERROR ./rubikstateERRORS.dat
% acroread filename.pdf &
%\end{verbatim}
%\end{quote}
%
%
% \subsection{Test file}
%
% An example tex file (which demonstrates the use of some of the package commands)
% is included in the package, namely:
%\begin{quote}
% \begin{verbatim}
% example-rot.tex (shows 8 worked examples)
%\end{verbatim}
%\end{quote}
% This file needs to be run using \texttt{--shell-escape} switch; for example:
%\begin{quote}
% \begin{verbatim}
% pdflatex --shell-escape example-rot.tex
%\end{verbatim}
%\end{quote}
% Batch files (\texttt{.sh} for Linux, and \texttt{.bat} for Microsoft) are also provided
% to facilitate running the `example' file.
% For example, on a Linux platform one would run a \texttt{bash} file as follows:
%\begin{quote}
% \begin{verbatim}
% bash example-rot.sh
%\end{verbatim}
%\end{quote}
% If processing this file gives unexpected results (e.g.,~the cubes appear not to
% have experienced any rotations) check-out the associated log file to see if
% the operating system had any difficulties finding files etc.
%
%
% \subsection{Configuration-file}
% \label{sec:configfile}
%
% A plain-text configuration-file with the name \texttt{rubikrotation.cfg}
% (if one exists) will automatically be read by \texttt{rubikrotation.sty}.
% The \rubikrotation\ package's facility to use a configuration-file allows the
% user to change not only (a)~the filename of the Perl script (\texttt{rubikrotation.pl}),
% but also (b)~the command-line code used by \texttt{rubikrotation.sty} for calling the
% Perl script. This~sort of fine-tuning can be very useful, and sometimes may
% even be necessary (depending on your system) for running the Perl script.
%
% For example, on some systems it maybe preferable to use a different \textsc{path},
% file-name and/or a different command-line code to call the script.
% Such~a configuration-file can also facilitate testing a new Perl script having
% a different name and location.
%
%
% \DescribeMacro{\rubikperlname}
% \DescribeMacro{\rubikperlcmd}
% The configuration-file is essentially a convenient software vehicle for feeding
% additional \LaTeX\ code to the style option \texttt{rubikrotation.sty}, and hence
% allows the contents of some commands to be easily adjusted and/or fine-tuned.
% For~the \rubikrotation\ package there are two particular commands we may wish to adjust.
% The~first is that defining the filename of the Perl script, namely
% \cmd{\rubikperlname}. The second is that defining the command-line call,
% namely \cmd{\rubikperlcmd}.
% The~default definitions in \texttt{rubikrotation.sty} (which assume the Perl
% script is executable), are as follows: (they are detailed in
% Section~\ref{sec:usefulcommands})
%\begin{quote}
%\begin{verbatim}
% \newcommand{\rubikperlname}{rubikrotation}
% \newcommand{\rubikperlcmd}{\rubikperlname\space%
% -i rubikstate.dat -o rubikstateNEW.dat}
%\end{verbatim}
%\end{quote}
% Note the need here to use the \cmd{\space} command on the end of the backslash
% command (\cmd{\rubikperlname}) in order to force a following
% space---i.e.,~before the first command-line argument. The following examples
% illustrate how the configuration-file may be used.
%
% \medskip
% {\noindent}\textsc{example~1}:\ \ Suppose we wish to test out
% a slightly modified Perl script
% with the working (executable) name \texttt{rubikrotationR77}. In this case we
% simply create, in the local working directory, a plain-text configuration-file
% (called \texttt{rubikrotation.cfg}) which contains just the following line:
%\begin{quote}
%\begin{verbatim}
%\renewcommand{\rubikperlname}{rubikrotationR77}
%\end{verbatim}
%\end{quote}
%
% \medskip
% {\noindent}\textsc{example~2}:\ \ Alternatively, suppose we wish to test out
% a new Perl script with the (non-executable) name \texttt{rubikrotationR55.pl}.
% Now, in this particular case we will need to run the script using a
% slightly different command, namely,
% {\linebreak}\texttt{perl rubikrotationR55.pl ...}, and consequently we
% need to implement both these changes in the configuration-file, as follows:
%\begin{quote}
%\begin{verbatim}
%\renewcommand{\rubikperlname}{rubikrotationR55.pl}
%\renewcommand{\rubikperlcmd}{perl \rubikperlname\space\%
% -i rubikstate.dat -o rubikstateNEW.dat}
%\end{verbatim}
%\end{quote}
%{\noindent}\textsc{placing the configuration-file}:\ \ The simplest arrangement is
% just to include the \texttt{.cfg} file in the working `test' directory.
% Alternatively, the \texttt{.cfg} file could be placed in the \texttt{/texmf-local/}
% directory tree (say, in \path!/usr/local/texlive/texmf-local/tex/latex/rubik/!),
% but in this case one would then have to be careful to specify the
% correct PATH for everything in order to enable your system to find all the
% various components etc.
%
% Note that you can, of course, have several \texttt{.cfg} files, since the system will
% read only one such file (the first one it finds starting with the current working
% directory). Consequently, it may be useful to have one \texttt{.cfg} file in
% your \texttt{/texmf-local/} dir (for running the standard Rubik package),
% and another (different) \texttt{.cfg} file in your `test' directory.
%
%
% \section{Commands}
%
% The \textit{only} `Rubik bundle' commands which \textit{must} be used inside a TikZ picture
% environment are the \cmd{\Draw...} commands (these are all provided by
% the \textsc{rubikcube} package), although most commands can be placed
% inside a TikZ environment if you wish.
%
% However, using commands which influence the Rubik colour state
% (e.g.,~the \cmd{\RubikRotation} command) outside the \texttt{tikzpicture},
% \texttt{minipage} or \texttt{figure} environments
% generally offers maximum flexibility, since the effects of such commands when
% used inside these environments remain `local' to the environment, and are not
% therefore accessable outside that \textit{particular} environment
% (see also Section~4.1 in the \textsc{rubikcube} documentation).
%
% Conversely, the only \rubikrotation\ command which should \textit{not}
% be used inside a TikZ environment is the \cmd{\ShowRubikErrors} command
% (see the notes on this command below).
%
%
% \subsection[RubikRotation command]{\cmd{\RubikRotation} command}
% \label{sec:rubikrotationcmd}
%
% \DescribeMacro{\RubikRotation}
% The \cmd{\RubikRotation}\oarg{integer}\marg{comma separated sequence}
% command processes a comma separated sequence of rotations, and returns
% the final state. The optional \oarg{integer} argument specifies the number
% of times the command should be repeated.
%
% For example, if we wanted to see the effect of the rotations
% \textbf{R, R, L, U, D} on a solved Rubik cube, we could use the
% following commands.
%\begin{quote}
% \begin{verbatim}
% \RubikCubeSolved % sets up the colours for a solved cube state
% \RubikRotation{R2,L,U,D}
% \begin{tikzpicture}[scale=0.7]
% \DrawRubikCubeRU
% \end{tikzpicture}%
%\end{verbatim}
%\end{quote}
% The \cmd{\RubikRotation} command results in \LaTeX\ first writing
% the current Rubik state to a text file (\texttt{rubikstate.dat}),
% and then calling the Perl script \texttt{rubikrotation.pl}. The Perl
% script then reads the current Rubik state from the (\texttt{rubikstate.dat})
% file, performs all the rotations, and then writes the new Rubik state
% (and any error messages) to the file \texttt{rubikstateNEW.dat},
% which is then input on-the-fly by the \LaTeX\ file. This new Rubik state
% can then either used as the input for another \cmd{\RubikRotation}, or used
% to generate a graphic image of the cube.
%
% A given rotation sequence can be repeated multiple times, say $n$ times, by
% using the optional \verb![n]!. For example, the following two commands are equivalent:
%\begin{quote}
% \begin{verbatim}
% \RubikRotation[3]{x,R,U}
% \RubikRotation{x,R,U,x,R,U,x,R,U}
%\end{verbatim}
%\end{quote}
%
% \subsubsection{Sequences as macros}
% \label{sec:seq-as-macros}
%
% Macros which are arguments of the \TeX\ \cmd{\write} command are expanded
% on writing (Eijkhout 1992, \S\,30.2.3, p.\,238)[\,see refs Section~\ref{sec:references}\,].
% Consequently we are able to use a sequence-defining macro as an argument for
% the \cmd{\RubikRotation} command. In fact this is very convenient, since it allows
% one to store lots of different rotation sequences by name alone.
%
% For example, we can use the name `sixspot' for a macro denoting the rotation sequence
% which generates the well known `sixspot' configuration (see the `patterns' page on the
% Reid website)[\,see refs Section~\ref{sec:references}\,], as follows:
%\begin{quote}
% \begin{verbatim}
% \newcommand{\sixspot}{U,Dp,R,Lp,F,Bp,U,Dp}
%\end{verbatim}
%\end{quote}
% With this new \cmd{\sixspot} command we are now able to generate the graphic (sixspot cube)
% very easily using the following code---this time we demonstrate the use of the more convenient
% \cmd{\ShowCube} command (which includes the \texttt{tikzpicture} environment):
%
% \medskip
%
% \begin{minipage}{6cm}
% \begin{verbatim}
% \RubikCubeSolved
% \RubikRotation{\sixspot}
% \ShowCube{3cm}{0.7}{\DrawRubikCubeRU}
%\end{verbatim}
% \end{minipage}
% \begin{minipage}{3.4cm}
% \centering
% \ifpdf
% \includegraphics[height=3cm]{Rubikrot-doc-figA.pdf}
% \else
% \fi
% \end{minipage}
%
% \medskip
% Providing such macros (when used as arguments) are comma separated (as the rotation codes
% must be), then the \cmd{\RubikRotation} command can accommodate both rotation codes
% and macros; for example, \verb!\RubikRotation{x,y,\sixspot,x}!.
%
%
% \subsubsection{Arguments prefixed with *, [, ]}
% \label{sec:prefixedargument}
%
% If any of the comma separated arguments is prefixed with either *, [ or ] they are
% interpreted as an inactive `string', and not as a rotation. This feature therefore
% allows a string argument to be used as a label, which can be very useful.
%
% For example, we can use this facility to label the `sixspot' configuration mentioned above,
% as follows:
%\begin{quote}
% \begin{verbatim}
% \RubikRotation{[sixspot],U,Dp,R,Lp,F,Bp,U,Dp}
%\end{verbatim}
%\end{quote}
% In practice, it is quite useful to go one step further and include
% the [\,] label feature in the \cmd{\sixspot} command, as follows,
%\begin{quote}
% \begin{verbatim}
% \newcommand{\sixspot}{[sixspot],U,Dp,R,Lp,F,Bp,U,Dp}
%\end{verbatim}
%\end{quote}
% since this has the great advantage of making the label-name visible in the log file.
% For example, the following command, which uses the rotations \textbf{x}, \textbf{x}
% and \textbf{y} to initially rotate the `solved' cube before applying
% the `sixspot' sequence of rotations,
%\begin{quote}
% \begin{verbatim}
% \RubikRotation{x2,y,\sixspot}
%\end{verbatim}
%\end{quote}
% will then be represented in the log file as
%\begin{quote}
% \begin{verbatim}
% ...command=rotation,x2,y,[sixspot],U,Dp,R,Lp,F,Bp,U,Dp
% ...arguments passed to `rotation' sub = x2 y [sixspot] U Dp R Lp F ...
% ...rotation x OK (= rrR + rrSr + rrLp)
% ...rotation x OK (= rrR + rrSr + rrLp)
% ...rotation y OK (= rrU + rrSu + rrDp)
% ...[sixspot] is a label OK
% ...rotation U OK
% ...rotation Dp OK
% ...rotation R OK
% ...rotation Lp OK
% ...rotation F OK
% ...rotation Bp OK
% ...rotation U OK
% ...rotation Dp OK
%\end{verbatim}
%\end{quote}
% In this way, several named rotation sequences can be easily distinguished
% in the log file from adjacent rotation sequences.
% This feature is also useful when typesetting a sequence of rotation codes, since the first
% element will then appear in the form \verb![name]!, obviating the need to typeset the
% name of the sequence separately.
%
% To this end, the
% \verb!ForEachX! macro---from the \verb!forarray! package---can be very useful.
% For example, this macro is central to the following example macro for typesetting
% a rotation sequence using the Rubik \cmd{\rr} command:
%\begin{quote}
%\begin{verbatim}
%\def\x{\thislevelitem}
%\def\xcount{\thislevelcount}
%
%\newcommand{\showseq}[1]{%
% \ForEachX{,}{%
% \ifthenelse{\xcount=1}{\texttt{\x}}{,\ \rr{\x}}%
% }{#1}.
%}
%\end{verbatim}
%\end{quote}
% Now, for a sequence defined as |\newcommand{\myseq}{[myseq],U,D,Lwp,R}|, then
% the command |\showseq{\myseq}| will result in the following output:
%\begin{quote}
% \texttt{[myseq]},\ \textbf{U},\ \textbf{D},\ \textbf{Lwp},\ \textbf{R}.
%\end{quote}
% Note that we are able to typeset the name \texttt{[myseq]} differently from the
% remaining sequence since the counter \verb!\xcount! allows us to locate the first item.
% However, this macro as it stands needs further development in order to handle
% sequence elements with a terminal digit (e.g.,~\texttt{R2})---the macro will need
% to first expand this to \texttt{R, R} if the Rubik commands are to be used.
%
% \subsubsection{Groups}
%
% The \cmd{\RubikRotation} command is a convenient tool for
% illustrating how Rubik rotations and sequences of rotations are elements
% of groups and subgroups.
% For~example, using the \rubikrotation\ package it is easy to
% show that three cycles of the `sixspot' sequence return the Rubik cube to its
% original state. More formally this is equivalent to $($\cmd{\sixspot}$)3 \equiv 0$,
% and can be nicely illustrated by implementing the following pseudocode:
%\begin{verbatim}
% \RubikCubeSolved . \RubikRotation[3]{\sixspot} = \RubikCubeSolved
%\end{verbatim}
%
% \begin{minipage}{11cm}
% \centering
% \ifpdf
% \includegraphics[width=10cm]{Rubikrot-doc-figC.pdf}
% \else
% \fi
% \end{minipage}
%
%
% \subsubsection{Random rotations}
%
% The \cmd{\RubikRotation} command can also be used to scramble the
% cube using a random sequence of rotations. If the first argument
% is the lowercase word `random' \textsc{and} the second argument
% is an integer $n$, ($1\leq n \leq 200$), then a random sequence
% of $n$ rotations will be performed; otherwise a default value
% of 50 is used (for example, if the second argument is not an integer).
% If $n > 200$ then the currently set maximum value $n=200$ will be used.
%
% As a safety feature the maximum $n$ can be changed only by editing the
% set value of the Perl variable \verb!$maxn! in the Perl script
% \texttt{rubikrotation.pl}, where (see line~583) we currently have
%\begin{quote}
%\begin{verbatim}
% my $maxn=200;
%\end{verbatim}
%\end{quote}
%
% For example, the following commands will scramble a solved cube using a
% sequence of 120 random rotations, and display the state in the form of
% a semi-flat cube.
%
% \begin{minipage}{3.4cm}
% \centering
% \ifpdf
% \includegraphics[height=4cm]{Rubikrot-doc-figB.pdf}
% \else
% \fi
% \end{minipage}
% \begin{minipage}{6cm}
% \vspace{1.6cm}
%\begin{verbatim}
% \RubikCubeSolved%
% \RubikRotation{random,120}%
% \ShowCube{5.5cm}{0.5}{\DrawRubikCubeFlat}
%\end{verbatim}
% \end{minipage}
%
% Note that in this particular example (above), only
% the \cmd{\Draw..} command is inside the TikZ picture environment (i.e.,~inside
% the \cmd{\ShowCube} command). Note also that when Rubik
% commands are outside a TikZ picture environment, they should have a
% trailing \% to stop additional white space being included.
%
% \medskip
%
% The randomisation procedure is as follows: all the possible rotations are first allocated
% a different cardinal number (positive integer) and collected into an array.
% Then a sequence of $n$ randomised numbers is generated and mapped to
% the array to generate the associated sequence of random rotations.
% The sequence used is detailed in the \texttt{.log} file.
%
%
% \subsection[SaveRubikState]{\cmd{\SaveRubikState} command}
% \label{saverubikstate}
%
% \DescribeMacro{\SaveRubikState}
% The command \cmd{\SaveRubikState}\marg{filename} saves the state (configuration)
% of the Rubik cube to the file \marg{filename} in the standard \cmd{\RubikFace...}
% format so that it can be read by \LaTeX. Consequently such a file can then be input
% so it can be drawn or processed in the usual way. The output file is `closed' immediately
% following the `write' in order to allow it to be available for input later by the same
% file if required.
%
% For example, the following commands would save the so-called `sixspot' configuration
% (generated by the rotations \textbf{U, Dp, R, Lp, F, Bp, U, Dp})
% to the file \verb!sixspot.tex!.
%\begin{quote}
%\begin{verbatim}
% \RubikCubeSolved%
% \RubikRotation{*sixspot,U,Dp,R,Lp,F,Bp,U,Dp}%
% \SaveRubikState{sixspot.tex}%
%\end{verbatim}
%\end{quote}
% The form of the file \verb!sixspot.tex! will then be as follows---the
% filename (commented out) is automatically written to the top of the
% file for convenience.
%\begin{quote}
%\begin{verbatim}
% % filename: sixspot.tex
% \RubikFaceUp{O}{O}{O}{O}{W}{O}{O}{O}{O}%
% \RubikFaceDown{R}{R}{R}{R}{Y}{R}{R}{R}{R}%
% \RubikFaceLeft{Y}{Y}{Y}{Y}{B}{Y}{Y}{Y}{Y}%
% \RubikFaceRight{W}{W}{W}{W}{G}{W}{W}{W}{W}%
% \RubikFaceFront{G}{G}{G}{G}{O}{G}{G}{G}{G}%
% \RubikFaceBack{B}{B}{B}{B}{R}{B}{B}{B}{B}%
%\end{verbatim}
%\end{quote}
% We can therefore access and draw this configuration later, when required,
% simply by inputting the file as follows:
%\begin{quote}
%\begin{verbatim}
%\input{sixspot.tex}
%\ShowCube{7cm}{0.7}{\DrawRubikCubeFlat}
%\end{verbatim}
%\end{quote}
%
%
% \subsection[CheckRubikState]{\cmd{\CheckRubikState} command}
%
% \DescribeMacro{\CheckRubikState}
% Since it is easy to inadvertently define an invalid Rubik cube
% (e.g.,~enter an invalid number of, say, yellow facelets), this command
% checks the current colour state of all the cubies
% of a 3x3x3 Rubik cube, and shows the number of facelets of each colour.
% An ERROR: code is issued if the number of facelets having a given colour exceeds~6.
% The results are written to the the \texttt{.log} file, and displayed under
% the graphic if the \cmd{\ShowRubikErrors} command is used.
%
% One can check the current Rubik state (for errors) by issuing the command
%\begin{quote}
%\begin{verbatim}
% \CheckRubikState%
%\end{verbatim}
%\end{quote}
% Note that such a check is implemented automatically with each \cmd{\RubikRotation} command.
%
%
%
%
% \subsection[ShowRubikErrors]{\cmd{\ShowRubikErrors} command}
%
% \DescribeMacro{\ShowRubikErrors}
% Any errors which arise can be made visible using the
% command \cmd{\ShowRubikErrors}.
% This command places a copy of the `error' file (\texttt{rubikstateERRORS.dat})
% underneath the graphic image so you can see any errors if there are any---all this
% detail can also be found in the \texttt{.log} file.
%
% Consequently, this command must be placed \textit{after} a TikZ picture
% environment---it cannot be used inside a TikZ environment. In fact this command
% is probably best placed at the end of the document (if there are several such
% environments), where it will reveal all rotation errors generated while
% processing the whole document.
% Once the document is free of errors this command can be removed or just commented out.
% Run the test file \texttt{example-rot.tex} to see an example of the use of this command.
%
% \section{Files generated}
%
%
% Whenever the \cmd{\RubikRotation} or \cmd{\CheckRubikState} commands are used,
% three small temporary plain-text files for holding data are generated as
% follows (they are refreshed with each \LaTeX\ run, and are not actively deleted).
% \begin{itemize}
% \item \LaTeX\ writes Rubik state data to the file \texttt{rubikstate.dat}.
%
% \item The Perl script \texttt{rubikrotation.pl} reads the file
% \texttt{rubikstate.dat} and then writes
% the new rubik state to the file \texttt{rubikstateNEW.dat}.
%
% \item The Perl script \texttt{rubikrotation.pl} also writes error data
% to the file \texttt{rubikstateERRORS.dat}. A copy of this file is displayed
% under the graphic image when the command
% \cmd{\ShowRubikErrors} is used after the TikZ picture environment.
%
% \end{itemize}
%
%
% \section{General overview}
% \label{generaloverview}
% When \LaTeX\ processes \texttt{rubikrotation.sty} the following steps
% are implemented.
% \begin{itemize}
%
%
% \item[1.] A check is made to see if \texttt{fancyvrb.sty} is loaded: if not
% then this package is loaded if it is available (this package is required
% for inputting the file \texttt{rubikstateERRORS.dat}).
%
% \item[2.] A check is made to see if a configuration-file (\texttt{rubikrotation.cfg})
% exists: if so then this file is input.
%
% \item[3.] The text file \texttt{rubikstateNEW.dat} is overwritten (if it exists):
% otherwise the file is created (this prevents an `old' file being used by \LaTeX).
%
% \item[4.] The plain-text file \texttt{rubikstateERRORS.dat} is created.
% This file collects error messages generated by the Perl script.
%
% \end{itemize}
%
%
% When a \cmd{\RubikRotation} command is processed it first writes the current
% colour configuration of each face (the `rubik state') to the temporary file
% \texttt{rubikstate.dat} (to be read by the Perl script \texttt{rubikrotation.pl}).
% The \cmd{\RubikRotation} command also appends the keyword `\texttt{checkrubik}'
% as well as a copy of the string of Rubik rotations.
% It~then calls the Perl script \texttt{rubikrotation.pl}.
%
% For example, if we use the command \cmd{\RubikCubeSolved}
% followed by the command \verb!\RubikRotation[2]{U,D,L,R}!, then the associated
% \texttt{rubikstate.dat} file would be as follows:
%\begin{quote}
% \begin{verbatim}
% % filename: rubikstate.dat
% up,W,W,W,W,W,W,W,W,W
% down,Y,Y,Y,Y,Y,Y,Y,Y,Y
% left,B,B,B,B,B,B,B,B,B
% right,G,G,G,G,G,G,G,G,G
% front,O,O,O,O,O,O,O,O,O
% back,R,R,R,R,R,R,R,R,R
% checkstate
% rotation,U,D,L,R
% rotation,U,D,L,R
%\end{verbatim}
%\end{quote}
% Note that the \cmd{\RubikRotation} option \texttt{[2]} results in the line \texttt{rotation,U,D,L,R}
% being written twice to the \texttt{rubikstate.dat} file, as shown above.
%
% Alternatively, if we used the command
% \verb!\RubikRotation{random, 45}! then the last line written to the file
% would be the string `\texttt{rotation,random,45}', as follows:
%\begin{quote}
% \begin{verbatim}
% % filename: rubikstate.dat
% up,W,W,W,W,W,W,W,W,W
% down,Y,Y,Y,Y,Y,Y,Y,Y,Y
% left,B,B,B,B,B,B,B,B,B
% right,G,G,G,G,G,G,G,G,G
% front,O,O,O,O,O,O,O,O,O
% back,R,R,R,R,R,R,R,R,R
% checkstate
% rotation,random,45
%\end{verbatim}
%\end{quote}
% A \cmd{\CheckRubikState} command triggers the same sequence of events except
% no `rotation' line is written.
%
% The action of the Perl script \texttt{rubikrotation.pl} is controlled by
% the keywords (first argument of
% each line) associated with each line of the file \texttt{rubikstate.dat}.
% When control passes to Perl, the script \texttt{rubikrotation.pl} starts
% by loading the current rubikstate (prompted by the keywords \texttt{up}, \texttt{down},
% \texttt{left}, \texttt{right}, \texttt{front}, \texttt{back}, in the file
% \texttt{rubikstate.dat}). Next the Perl script
% performs some basic checks (prompted by the key word \texttt{checkstate}), and
% then it processes the sequence of Rubik rotations (prompted by the keyword
% \texttt{rotation}). If, instead, the second argument of the `rotation' string
% is the keyword `random', and provided this is followed by a valid integer, say $n$,
% then the Perl script performs a sequence of $n$ random rotations.
% Finally, the Perl script writes the final `rubikstate' to the text file
% \texttt{rubikstateNEW.dat}. All error messages are written to the
% text file \texttt{rubikstateERRORS.dat} and also to the \LaTeX\ log file.
%
% Control then reverts to \LaTeX\ which then inputs the file
% \texttt{rubikstateNEW.dat}. If there are more \cmd{\RubikRotation} commands
% then this cycle repeats accordingly. Eventually a \cmd{\Draw...} command
% of some form is reached and the final rubikstate is drawn in a TikZ picture
% environment.
%
% If the TikZ picture environment is followed by a \cmd{\ShowRubikErrors} command,
% then a `verbatim' copy of the \texttt{rubikstateERRORS.dat} file is displayed
% immediately under the graphic. Once the graphic is error-free, then the
% \cmd{\ShowRubikErrors} command can be removed or commented out.
%
% Note that if a \textsc{bash} file is used to coordinate the process then it is often
% convenient to use the linux \texttt{grep} utility to alert the user to any run-time errors,
% by using \texttt{grep} to scan the \texttt{rubikstateERRORS.dat} file at the end of
% the run; for example, as follows:
%\begin{quote}
%\begin{verbatim}
% pdflatex --shell-escape myfile.tex
% echo "...checking error file"
% grep ERROR ./rubikstateERRORS.dat
%\end{verbatim}
%\end{quote}
%
%
% \section{References}
% \label{sec:references}
%
%\begin{itemize}
%
% \item Abrahams PW, Berry K and Hargreaves KA (1990). \textit{\TeX\ for the impatient}
% (Addison-Wesley Publishing Company), page~292.
% {\newline}Available from: \url{http://www.ctan.org/pkg/impatient}
% {\newline}[\,re:~\cmd{\rubikpercentchar} and \cmd{\@comment} in Section~\ref{sec:abrahams}\,]
%
%
% \item Eijkhout V (1992). \textit{\TeX\ by topic: a {\TeX}nician's reference}.
% (Addison-Wesley Publishing Company), pages~232 \&~238.
% {\newline}Available from: \url{https://bitbucket.org/VictorEijkhout/tex-by-topic/}
% [\,re:~\cmd{\string} in Section~\ref{sec:eijkhout}\,]
% [\,re:~\cmd{\write} in Section~\ref{sec:seq-as-macros}\,]
%
%
% \item Feuers\"{a}nger C (2015). Notes on programming in \TeX.
% {\newline}(revision: 1.12.1-32-gc90572c; 2015/07/29)
% \newline\url{http://pgfplots.sourceforge.net/TeX-programming-notes.pdf}
% {\newline}[\,re:~loop macros in Section~\ref{sec:feuersanger}\,]
%
%
% \item Nickalls RWD and Syropoulos A (2015). The \textsc{rubikcube} package.
% \newline\url{http://www.ctan.org/pkg/rubik},
%
% \item Reid M. \ Patterns. \url{http://www.cflmath.com/Rubik/patterns.html}
% {\newline}[\,re:~sequences as macros; in Section~\ref{sec:seq-as-macros}\,]
%
%\end{itemize}
%
%
%
% \section{Change history}
%
% \begin{itemize}
% \item Version 3.0 (25 September 2015)
%
% --- The \cmd{\RubikRotation} command now actions multiple instances of its argument
% as determined by an optional `repeat' \oarg{integer}. For example the command
% \cmd{\RubikRotation[3]\{R,x\}} is equivalent to the command \cmd{\RubikRotation\{R,x,R,x,R,x\}}
% (see Sections~\ref{sec:rubikrotationcmd} and \ref{sec:rubikrotationcode}).
%
% --- If a comma separated element used as an argument for the \cmd{\RubkRotation}
% command is prefixed with either a * or [ or ] character then it is not actioned
% as a rotation (see Section~\ref{sec:prefixedargument}).
%
% --- The Perl script \texttt{rubikrotation.pl} now has command-line switches,
% including \texttt{-h} to show some `help' and `usage' information
% (see Section~\ref{sec:placingfiles}).
%
% --- A `man' file for the Perl script \texttt{rubikrotation.pl} is now included in the package.
%
% --- The Perl script \texttt{rubikrotation.pl} now uses as input and output filenames
% those specified in the command-line of the CALLing program. This now allows the
% script \texttt{rubikrotation.pl} to be used as a stand-alone tool (see the
% \texttt{rubikrotation} `man' file for details).
%
% --- The documentation for the Perl script \texttt{rubikrotation.pl} is in the
% accompanying file \texttt{rubikrotationPL.pdf}.
%
% --- Fixed typos, index and minor errors in the documentation.
%
%
% \item Version 2.0 (5 February, 2014)
%
% --- First release.
%
% \end{itemize}
%
% ^^A ==================================================
% \StopEventually{\PrintIndex}
%
%
%
% \section{The code (\texttt{rubikrotation.sty})}
%
% {\noindent}In the following, the term `Perl script' denotes the script
% \texttt{rubikrotation.pl}. Useful information regarding the
% \TeX\ \cmd{\write} command is given in Eijkhout (1992), \S\,30.2.3 (page~238).
% For the means of including a `\%' character in the token list of \cmd{\write} see
% Abrahams \textit{et.~al} (1990).
%
% \subsection{Package heading}
%
% \begin{macrocode}
%<*rubikrotation>
\def\RRfileversion{3.0}%
\def\RRfiledate{2015/09/25}%
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{rubikrotation}[\RRfiledate\space (v\RRfileversion)]
% \end{macrocode}
%
%
% {\noindent}The package requires \texttt{rubikcube.sty}. However \texttt{rubikcube.sty}
% is not automatically loaded (for the moment at least) since this makes it difficult
% to errorcheck new versions.
% \begin{macrocode}
\@ifpackageloaded{rubikcube}{}{%
\typeout{---rubikrotation requires the rubikcube package.}%
}%
% \end{macrocode}
%
%
%
% {\noindent}The \rubikrotation\ package requires access to the fancyvrb package
% for the \cmd{\VerbatimInput\{\}} command which we use for inputting and displaying
% the error file (see Section~\ref{sec:showrubikerrors}).
% \begin{macrocode}
\@ifpackageloaded{fancyvrb}{}{%
\typeout{---rubikrotation requires the fancyvrb package%
for VerbatimInput{} command.}%
\RequirePackage{fancyvrb}}
% \end{macrocode}
%
% \medskip
%
% \subsection{Some useful commands}
% \label{sec:usefulcommands}
%
% \begin{macro}{\rubikrotation}
% First we create a suitable logo
% \begin{macrocode}
\newcommand{\rubikrotation}{\textsc{rubikrotation}}
\newcommand{\Rubikrotation}{\textsc{Rubikrotation}}
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\@print}
% We need a simple print command to facilitate writing output to a file.
% \begin{macrocode}
\newcommand{\@print}[1]{\immediate\write\outfile{#1}}
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\@comment}
% \begin{macro}{\@commentone}
% We also require access to the `\%' character so we can (a)~write comments to
% files, including the log file, and (b)~place a trailing `\%' in a line of code
% written to a file.
%
% To achieve this we define the `\%' character as \cmd{\rubikpercentchar}
% (modified from: Abrahams PW, Berry K and Hargreaves KA (1990), p~292)
% [see refs Section~\ref{sec:references}]\label{sec:abrahams},
% and also two `comment' commands which implement it. This `workaround'
% is necessary because \TeX\ does not allow the use of the \cmd{\%} command
% for placing a `\%' character in the token list of \cmd{\write}.
% See Abrahams \textit{et.~al} (1990) for details.
% \begin{macrocode}
{\catcode`\%=12 \global\def\rubikpercentchar{%}}%
\newcommand{\@comment}{\rubikpercentchar\rubikpercentchar\space}%
\newcommand{\@commentone}{\rubikpercentchar}%
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
%
% \begin{macro}{\rubikperlname}
% This holds the name of the Perl script. A configuration-file
% (\verb!rubikrotation.cfg!) can be used to change the default name of the
% Perl script using a renewcommand (see Section~\ref{sec:configfile}).
% \begin{macrocode}
\newcommand{\rubikperlname}{rubikrotation}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\rubikperlcmd}
% This holds the command-line code for calling the Perl script
% (assumed to be an executable file).
% Note that the command-line requires a mandatory input filename preceded
% by the \texttt{-i}~switch. An optional output filename (preceded by the
% \texttt{-o}~switch) may be used, otherwise the default output filename of
% \texttt{rubik-OUT.dat} will be used.
%
% Note that it is very important that this .sty file actually specifies an
% output filename (for receiving data from the Perl script). This is because
% (a)~The Perl script \texttt{rubikrotation.pl} is currently configured to read its
% output filename as an argument from the command-line (so it can be flexibly
% used as a stand-alone script for processing a given Rubik state through a
% sequence of rotations), and (b)~\texttt{rubikrotation.sty} is currently
% configured to read its input from the file \texttt{rubikstateNEW.dat}.
% \begin{macrocode}
\newcommand{\rubikperlcmd}{\rubikperlname\space%
-i rubikstate.dat -o rubikstateNEW.dat}
% \end{macrocode}
% Remember to use the \cmd{\space} command following the \LaTeX\ backslash
% command in order to generate the mandatory space between it and the first
% command-line argument).
%
% A plain-text configuration-file \verb!rubikrotation.cfg! can be used to
% change the default command-line code using a renewcommand
% (see Section~\ref{sec:configfile}).
% \end{macro}
%
%
% \subsection{Configuration file}
%
% If a configuration file exists (\texttt{rubikrotation.cfg}) then input it here,
% i.e.,~\textit{after} defining the \cmd{\rubikperlname} and \cmd{\rubikperlcmd}
% commands and \textit{before} creating the \texttt{rubikstateERRORS.dat} file.
% \begin{macrocode}
\typeout{---checking for config file (rubikrotation.cfg)...}
\IfFileExists{rubikrotation.cfg}{%
\input{rubikrotation.cfg}%
}{\typeout{---no config file available}%
}%
% \end{macrocode}
%
%
% \subsection{Clean file rubikstateNEW.dat}
%
% {\noindent}We need to clean out any existing (old) rubikstateNEW.dat file,
% since if the TeX shell command-line switch is accidentally not used then the Perl script
% \texttt{rubikrotation.pl} will not be CALLed, and hence this file will not be renewed
% (i.e.,~an `old' image may be used).
% \begin{macrocode}
\typeout{---cleaning file rubikstateNEW.dat}%
\newwrite\outfile%
\immediate\openout\outfile=rubikstateNEW.dat%
\@print{\@comment rubikstateNEW.dat}%
\immediate\closeout\outfile%
% \end{macrocode}
%
%
% \subsection{rubikstateERRORS.dat}
%
% {\noindent}We first open the file \texttt{rubikstateERRORS.dat} which is used
% by the Perl script \texttt{rubikrotation.pl} for writing its error-messages to.
% This file is displayed by the command
% \cmd{\ShowRubikErrors}.
%
% \textsc{important note}: this file is created fresh each time LaTeX is run,
% and hence the Perl script only appends data to it during the \LaTeX\ run,
% so this file just grows until either it is destroyed or recreated---this is
% a useful feature since the file accumulates all error messages as the
% \texttt{.tex} file is processed.
% We can't make the Perl script create the file since the Perl script is only
% CALLed if we use a \cmd{\RubikRotation} or \cmd{\CheckRubikState}
% command (which we may not\,!)---so it has to be created here.
% \begin{macrocode}
\typeout{---creating file rubikstateERRORS.dat}%
\newwrite\outfile%
\immediate\openout\outfile=rubikstateERRORS.dat%
\@print{\@comment rubikstateERRORS.dat}%
\@print{\@comment ---(RR.sty v\RRfileversion): comments output by Perl script}%
\immediate\closeout\outfile%
% \end{macrocode}
%
%
% \subsection{Setting up file-access for new files}
%
% Having set up all the primary files, we now need to set up a newwrite for
% all subsequent file openings (e.g.,~for \texttt{rubikstate.dat} and saving
% to arbitrary filenames by the \cmd{\SaveRubikState} command). Otherwise, we
% can easily exceed the LaTeX limit of 15. From here-on \TeX\ will use
% \texttt{openout7} when opening and writing to files. We will implement new
% openings using the command \verb!\@openstatefile! (see below).
% \begin{macrocode}
\typeout{---setting up newwrite for rubikrotation.sty to use...}%
\newwrite\outfile%
% \end{macrocode}
%
%
% \begin{macro}{\@openstatefile}
% \begin{macro}{\@closestatefile}
% We also need commands for easy file opening and closing
% for new instances of the file \texttt{rubikstate.dat} etc.
% Note that for this we are therefore using the same outfile number as set up
% by the \verb!\newwrite...! above.
% \begin{macrocode}
\newcommand{\@openstatefile}{\immediate\openout\outfile=rubikstate.dat}
\newcommand{\@closestatefile}{\immediate\closeout\outfile}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \subsection{Saving the Rubik state}
%
% \begin{macro}{\@printrubikstate}
% This internal command writes the Rubik configuration to
% the file \texttt{rubikstate.dat}, and is used by the \cmd{\RubikRotation} command
% (see Sections~\ref{saverubikstate} and \ref{generaloverview}).
% The file \texttt{rubikstate.dat} is read by the Perl script, and represents
% the state on which the new \cmd{\RubikRotation} command acts.
% Note that we append the key-word \texttt{checkstate} to the end of the file
% in order to trigger the Perl script to implement its \texttt{checkstate} subroutine.
%
% The actual state is simply an ordered sequence of the faces and the colours
% associated with each facelet of that face. The colour associated with a particular facelet
% is held by the variable for that facelet. For example, the top-left facelet associated with
% the \textsc{front} face is held in the variable \cmd{\Flt} (see Section~\ref{saverubikstate}).
% Further relevant documentation is in the \textsc{rubikcube} package.
% \begin{macrocode}
\newcommand{\@printrubikstate}{%
\@print{up,\Ult,\Umt,\Urt,\Ulm,\Umm,\Urm,\Ulb,\Umb,\Urb}%
\@print{down,\Dlt,\Dmt,\Drt,\Dlm,\Dmm,\Drm,\Dlb,\Dmb,\Drb}%
\@print{left,\Llt,\Lmt,\Lrt,\Llm,\Lmm,\Lrm,\Llb,\Lmb,\Lrb}%
\@print{right,\Rlt,\Rmt,\Rrt,\Rlm,\Rmm,\Rrm,\Rlb,\Rmb,\Rrb}%
\@print{front,\Flt,\Fmt,\Frt,\Flm,\Fmm,\Frm,\Flb,\Fmb,\Frb}%
\@print{back,\Blt,\Bmt,\Brt,\Blm,\Bmm,\Brm,\Blb,\Bmb,\Brb}%
\@print{checkstate}%
}
% \end{macrocode}
% \end{macro}
%
%
% \subsection{SaveRubikState command}
% \label{sec:eijkhout}
%
% \begin{macro}{\SaveRubikState}
% The command \cmd{\SaveRubikState}\marg{filename} saves the Rubik state
% to a named file in the format of a Rubik command (so it can then be processed
% by \LaTeX). Note that in order to actually write a LaTeX
% command to a file without a trailing space one must prefix the command with the
% \cmd{\string} command (see Eijkhout (1992), p~238)
% [see refs Section~\ref{sec:references}]\label{sec:eijkhout}.
%
% Note that this macro uses the internal commands \cmd{\@comment} (`\%\%'),
% \cmd{\@commentone} (`\%') and \cmd{\@print}. \#1 is the output filename.
% We use several \cmd{\typeout} commands to write to the log file.
% An example of the line of code we are trying to output to the
%\texttt{rubikstateNEW.dat} file is as follows:
% {\newline}\verb!\RubikFaceUp{W}{W}{G}{W}{W}{G}{B}{B}{Y}%!
% \begin{macrocode}
\newcommand{\SaveRubikState}[1]{%
\typeout{---NEW save command------------------}%
\typeout{---command = SaveRubikState{#1}}%
\typeout{---saving Rubik state data to file #1}%
\immediate\openout\outfile=#1%
\@print{\@comment filename: #1\@commentone}%
\@print{\string\RubikFaceUp%
{\Ult}{\Umt}{\Urt}{\Ulm}{\Umm}{\Urm}{\Ulb}{\Umb}{\Urb}\@commentone}%
\@print{\string\RubikFaceDown%
{\Dlt}{\Dmt}{\Drt}{\Dlm}{\Dmm}{\Drm}{\Dlb}{\Dmb}{\Drb}\@commentone}%
\@print{\string\RubikFaceLeft%
{\Llt}{\Lmt}{\Lrt}{\Llm}{\Lmm}{\Lrm}{\Llb}{\Lmb}{\Lrb}\@commentone}%
\@print{\string\RubikFaceRight%
{\Rlt}{\Rmt}{\Rrt}{\Rlm}{\Rmm}{\Rrm}{\Rlb}{\Rmb}{\Rrb}\@commentone}%
\@print{\string\RubikFaceFront%
{\Flt}{\Fmt}{\Frt}{\Flm}{\Fmm}{\Frm}{\Flb}{\Fmb}{\Frb}\@commentone}%
\@print{\string\RubikFaceBack%
{\Blt}{\Bmt}{\Brt}{\Blm}{\Bmm}{\Brm}{\Blb}{\Bmb}{\Brb}\@commentone}%
\immediate\closeout\outfile%
\typeout{-----------------------------------------}%
}%
% \end{macrocode}
% \end{macro}
%
%
% \subsection{RubikRotation command}
% \label{sec:rubikrotationcode}
%
% \begin{macro}{\RubikRotation}
% The \cmd{\RubikRotation}\oarg{integer}\marg{comma separated sequence}
% command (a)~writes the current Rubik state to the file \texttt{rubikstate.dat},
% (b)~writes the rotation sequence (either once or multiple times depending
% on the value of the optional integer argument), and then (c)~CALLs the
% Perl script \texttt{rubikrotation.pl}. It~also writes comments to the
% data file and also to the log file.
%
% In order to allow the user to (optionally) write the main argument multiple
% times to the output data-file, we require this command to allow an optional
% argument (a non-negative integer) to specify the number of such repeats.
% In order to implement an optional argument facility we use two macros
% (countingloop and loopcounter) detailed by Feuers\"{a}nger (2015)
% [\,see refs Section~\ref{sec:references}\,]\label{sec:feuersanger},
% as follows:
% \begin{macrocode}
%% Two macros detailed by Feuersaenger (2015)
\long\def\@countingloop#1 in #2:#3#4{%
#1=#2 %
\@loopcounter{#1}{#3}{#4}%
}
%%--------------------------
\long\def\@loopcounter#1#2#3{%
#3%
\ifnum#1=#2 %
\let\next=\relax%
\else
\advance#1 by1 %
\def\next{\@loopcounter{#1}{#2}{#3}}%
\fi
\next
}
% \end{macrocode}
% Having defined the above two macros we can now implement an optional
% argument (a repeat number) indicating the number of times we want
% the command to write the main argument to the output data file.
% \begin{macrocode}
\newcommand{\RubikRotation}[2][1]{%
\typeout{---NEW rotation command------------------}%
\typeout{---command = RubikRotation{#1}}%
\typeout{---writing current Rubik state to file rubikstate.dat}%
\@openstatefile% open data file
\@print{\@comment filename: rubikstate.dat}%
\@print{\@comment written by rubikrotation.sty%
=v\RRfileversion\space (\RRfiledate)}%
\@printrubikstate%
%% countingloop code from Feuersaenger (2015)
\newcount\ourRRcounter%
\@countingloop{\ourRRcounter} in 1:{#1}{%
\immediate\write\outfile{rotation,#2}}%
\@closestatefile% close data file
\typeout{---running Perl script (rubikrotation)}%
\immediate\write18{\rubikperlcmd}%
\typeout{---inputting NEW datafile (written by Perl script)}%
\input{rubikstateNEW.dat}%
\typeout{-----------------------------------------}%
}
% \end{macrocode}
% \end{macro}
%
%
% \subsection{ShowRubikErrors command}
% \label{sec:showrubikerrors}
%
% \begin{macro}{\ShowRubikErrors}
% This command inputs the file \texttt{rubikstateERRORS.dat}.
% \begin{macrocode}
\newcommand{\ShowRubikErrors}{%
\typeout{---ShowRubikErrors: inputting file rubikstateERRORS.dat}%
\VerbatimInput{rubikstateERRORS.dat}%
}
% \end{macrocode}
% \end{macro}
%
%
% \subsection{CheckRubikState command}
%
% \begin{macro}{\CheckRubikState}
% This command triggers the Perl script to implement
% some simple error checking of the Rubik configuration (state).
% This command (a)~writes the current Rubik state to the file
% \texttt{rubikstate.dat}, and then (b)~CALLs the Perl script.
% It also writes comments to the data file and also to the log file..
% \begin{macrocode}
\newcommand{\CheckRubikState}{%
\typeout{---NEW check command------------------}%
\typeout{---command = CheckRubikState}%
\typeout{---writing current Rubik state to file rubikstate.dat}%
\@openstatefile% opens data file
\@print{\@comment filename: rubikstate.dat}%
\@printrubikstate%
\@closestatefile% close data file
\typeout{---running Perl script (rubikrotation)}%
\immediate\write18{\rubikperlcmd}%
\typeout{---inputting NEW datafile (written by Perl script)}%
\input{rubikstateNEW.dat}%
\typeout{-----------------------------------------}%
}
% \end{macrocode}
% \end{macro}
%
%
% --------------------------
% End of this package
% --------------------------
% \begin{macrocode}
%
% \end{macrocode}
%
%
%
%
% \Finale
%
\endinput