% \iffalse meta-comment
%
% Copyright (C) 2019-2023 by Antoine Missier <antoine.missier@ac-toulouse.fr>
%
% This file may be distributed and/or modified under the conditions of
% the LaTeX Project Public License, either version 1.3 of this license
% or (at your option) any later version.  The latest version of this
% license is in:
%
%   http://www.latex-project.org/lppl.txt
%
% and version 1.3 or later is part of all distributions of LaTeX version
% 2005/12/01 or later.
% \fi
%
% \iffalse
%<*driver>
\ProvidesFile{spacingtricks.dtx}
%</driver>
%<*package> 
\NeedsTeXFormat{LaTeX2e}[2005/12/01]
\ProvidesPackage{spacingtricks}
    [2023/03/05 v1.6 .dtx spacingtricks file]
%</package>
%<*driver>
\documentclass{ltxdoc}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[english]{babel}
\usepackage{mathptmx}
\usepackage[pifont]{spacingtricks}
\usepackage{amsmath}
\usepackage{tikz}
\usepackage{sectsty}
\usepackage{xcolor}

\definecolor{darkbrown}{rgb}{0.5,0.1,0.1}
\allsectionsfont{\color{darkbrown}}
\DisableCrossrefs
%\CodelineIndex
%\RecordChanges
\usepackage{hyperref}
\hypersetup{%
    colorlinks,
    linkcolor=blue, %red by default
    citecolor=red, %green by default
    pdftitle={spacingtricks},
    pdfsubject={LaTeX package},
    pdfauthor={Antoine Missier}
}
\begin{document}
\DeleteShortVerb{\|}
\MakeShortVerb{\"}
\DocInput{spacingtricks.dtx}
%\PrintChanges
%\PrintIndex
\end{document}
%</driver>
% \fi
%
% \CheckSum{246}
%
% \CharacterTable
%  {Upper-case    \A\B\C\D\E\F\G\H\I\J\K\L\M\N\O\P\Q\R\S\T\U\V\W\X\Y\Z
%   Lower-case    \a\b\c\d\e\f\g\h\i\j\k\l\m\n\o\p\q\r\s\t\u\v\w\x\y\z
%   Digits        \0\1\2\3\4\5\6\7\8\9
%   Exclamation   \!     Double quote  \"     Hash (number) \#
%   Dollar        \$     Percent       \%     Ampersand     \&
%   Acute accent  \'     Left paren    \(     Right paren   \)
%   Asterisk      \*     Plus          \+     Comma         \,
%   Minus         \-     Point         \.     Solidus       \/
%   Colon         \:     Semicolon     \;     Less than     \<
%   Equals        \=     Greater than  \>     Question mark \?
%   Commercial at \@     Left bracket  \[     Backslash     \\
%   Right bracket \]     Circumflex    \^     Underscore    \_
%   Grave accent  \`     Left brace    \{     Vertical bar  \|
%   Right brace   \}     Tilde         \~}
%
%
% \changes{v0.1}{2011/12/27}{Initial version}
% \changes{v1.0}{2019/05/04}{dtx and ins files, adding the footnote command}
% \changes{v1.0}{2019/06/16}{English translation of the documentation}
%
% \changes{v1.1}{2019/09/06}{
%    - No automatic line breaking at the end of the centered command,
%    - new length compactitemlist}
%
% \changes{v1.2}{2019/09/09}{
%    - A bug correction in the last update}
%
% \changes{v1.3}{2020/11/02}{
%    - Loading the setspace package, 
%    - small changes in compactlist environment, 
%    - improvement in dualboxes macro}
%
% \changes{v1.4}{2021/09/21}{
%    - A mistake in the documentation is now corrected}
%
% \changes{v1.5}{2023/02/23}{
%    - Changing font to times (with the mathptmx package),
%    - changing pstricks figure to tikz to avoid double compilation,
%    - tests and comments about wrapfig and picinpar packages}
% \changes{v1.5}{2023/02/25}{
%    - adding the centeredline package,
%    - adding the pifont package as option,
%    - taking over the juxtapose environment from Christian Obrecht,
%    - topsep of indentblock environment reduced to zero}
% \changes{v1.5}{2023/02/26}{
%    - Tests and comments about paracol and reledpar packages}
%
% \changes{v1.6}{2023/03/05}{
%    - Any list symbol is followed by a space if there is no punctuation character after it,
%    - some changes in documentation}
%
% \GetFileInfo{spacingtricks.sty}
%
% \title{The \textsf{spacingtricks} package\thanks{This document
% corresponds to \textsf{spacingtricks}~\fileversion, dated \filedate.}}
% \author{Antoine Missier \\ \texttt{antoine.missier@ac-toulouse.fr}}
% \date{March 5, 2023}
% \maketitle
%
% \section{Introduction}
%
% This package offers a few macros to deal with spacing issues. Thus:
% \begin{compactlist}
% \item \hyperlink{centered}{\texttt{\bslash centered}} yields good horizontal 
% centering without vertical spacing;
% \item \hyperlink{footnote}{\texttt{\bslash footnote}} has been redefined 
% to avoid unsuitable spacing;
% \item \hyperlink{vstrut}{\texttt{\bslash vstrut}} produces a strut 
% with variable height or depth;
% \item \hyperlink{indent}{\texttt{\bslash indent}} has been redefined 
% to indent a line at the beginning 
% of a particular paragraph even if "\parindent" has been set to 0;
% \item the \hyperlink{indentblock}{\texttt{indentblock}} environment 
% produces indentation of all its content;
% \item the \hyperlink{compactlist}{\texttt{compactlist}} environment 
% yields a compact list, without vertical spacing between the items, like here;
% several aliases are provided to type some \hyperlink{symbols}{list symbols} shorter:
% "\bul", "\dash", "\ddash", "\aster", "\hand", "\checksymb", "\arrowsymb";
% \item common abbreviations \hyperlink{ie-eg}{\ie and \eg} 
% are typeset by the macros "\ie" and "\eg" with correct spacing;
% \item the \hyperlink{dualboxes}{\texttt{\bslash dualboxes}} command attends to place 
% two boxes (figures, tables, text) side by side by adjusting the vertical positioning.
% \end{compactlist}
% 
% \medskip
% Three other ``spacing'' packages are loaded by \textsf{spacingtricks}:
% \hyperlink{setspace}{\textsf{setspace}}~\cite{SETSP} (natively in \LaTeXe), 
% for setting line spacing in a piece of text,
% \textsf{xspace}~\cite{XSP}, which adds an inter-word space unless the macro 
% is followed by a punctuation character,
% and \hyperlink{centeredline}{\textsf{centeredline}}~\cite{CENTER} 
% which gives an interesting alternative 
% to our "\centered" macro (see further).
% We also took over the fine \hyperlink{juxtapose}{\texttt{juxtapose}} environment 
% from the \textsf{mafr}~\cite{MAFR}
% distribution, as another way to place boxes side by side.
%
% Otherwise, we have develop the package \textsf{arraycols}~\cite{ARCOL},
% that allows a good management of spacing in \texttt{tabular} 
% or \texttt{array} environments,
% and \textsf{mismath}~\cite{MSMATH} that provides several macros to improve spacing 
% in mathematical formulas.
%
% \section{Usage}
%
% \hypertarget{centered}{}
% \DescribeMacro{\centered}
% The "\centered"\marg{text} command yields a centered line without vertical spacing.
% It acts like "\centerline" except in lists or tables where its behavior is much better
% (see the following examples).
% Moreover, the line break before (but not after) the macro is automatic.
%
% Here is a comparative example of the centering commands inside a list:
% \begin{enumerate}
% \item Here a centered line with "\centered": 
% \centered{Lorem ipsum dolor sit amet, consectetuer adipiscing elit.}
% \item Here another centered line with "\\ \centerline":\\
% \centerline{Lorem ipsum dolor sit amet, consectetuer adipiscing elit.}
% \item Here another centered line with "\par\centerline":
% \par\centerline{Lorem ipsum dolor sit amet, consectetuer adipiscing elit.}
% \item Here a centered line with the \texttt{center} environment:
% \begin{center} Lorem ipsum dolor sit amet, consectetuer adipiscing elit. \end{center}
% \end{enumerate}
%
% After "\centered{...}", the end of line must be explicit, 
% otherwise "\centered" will not work. You can use "\\",
% which is equivalent to "\linebreak", or
% a blank line to begin a new paragraph (equivalent to "\par"). 
% In the former case, no vertical space
% is added after the centered line,  in the latter case, the vertical space
% following the centered line is a bit larger. 
% In the example above, the centered line comes to the end, without line breaking,
% because of the next "\item" command, and the vertical space is set by the
% \texttt{enumerate} environment.
%
% \medskip
% In tables, "\centered" allows to center a particular line in a cell independently of 
% the column alignment
% \footnote{In tables, we can also use the powerful \texttt{\bslash makecell} command
% of the \textsf{makecell} package~\cite{MKCELL}; on the other hand,
% neither \texttt{\bslash centerline} nor \texttt{\bslash centering} commands
% do work for a single line in a cell.},
% here with "\begin{tabular}{|l|r|}":
%
% \begin{center}
% \begin{tabular}{|l|r|}
% \hline
% left aligned column & right aligned column \\
% \hline
% the second cell fixes the width  & \centered{centered cell} \\
% \hline
% \centered{centered cell} & the last cell fixes the width \\
% \hline
% \end{tabular}
% \end{center}
%
% \medskip
% \hypertarget{centeredline}{}
% \DescribeMacro{\centeredline}
% A limitation of our "\centered" macro is that it doesn't allow to use \texttt{\bslash verb}
% commands inside its argument. For this purpose, you get
% the "\centeredline" command, from the package
% \textsf{centeredline} by Jean-François Burnol~\cite{CENTER}. 
% This small package is now loaded by \textsf{spacingtricks}.
% Another advantage of "\centeredline" is that it does not require an explicit
% end, the text can follow the command on the same line, and the line break will
% be automatic.
% Nevertheless, it doesn't work in tables (like in the example above),
% except with \texttt{p} column declaration.
%
% \hypertarget{setspace}{}
% \medskip
% \DescribeEnv{onehalfspace}\DescribeEnv{doublespace}\DescribeEnv{spacing}
% \begin{onehalfspace}
% The \textsf{setspace} package~\cite{SETSP}, loaded by \textsf{spacingtricks}, provides
% environments for changing the spacing between lines. The present paragraph is nested
% in a \texttt{onhalfspace} environment as you can see.
% The \texttt{spacing} environment can be used to get other interline spacing, \eg
% "\begin{spacing}{2.5}".
% \end{onehalfspace}
%
% \hypertarget{footnote}{}
% \medskip
% \DescribeMacro{\footnote}
% The "\footnote" command doesn't have a good management of spacing issues,
% in particular when the \textsf{hyperref} package has been loaded.
% In English tradition, there is no space before numbers (or symbols) of note calls,
% and likewise at the beginning of footnotes,
% text begins immediately after the note number
% \footnote{The typesetting of footnotes and note calls depends on national typographic
% rules which are, in principle, managed by \textsf{babel}.
% For instance, by activating the \texttt{french} option of \textsf{babel},
% a thin space is added before the note calls, and the new \texttt{\bslash footnote}
% macro does not alter this behavior.}.
% To avoid undesirable spaces, we don't have to put some space before 
% writing "\footnote{", for instance:
% \begin{center}
% "Here is no space\footnote{The old command} before the macro."
% \end{center}
% but sometimes, it is convenient to place the "\footnote" command
% on a new line. To achieve this, "\footnote" has been redefined to completely eliminate
% unwanted spaces
% \footnote{Probably it would have been enough to recommend the use of the \% symbol
% at the end of line; its effect is to cancel the space produced by a line break,
% but we do not always think of using it.}.
%
% \medskip
% \noindent\begin{minipage}{5.6cm}
% \begin{verbatim}
%This is a note 
%\footnote{ 
%The old command.}
%with bad spacing.
% \end{verbatim}
% \vspace{-4ex} 
% This is a note
% \footnt{
% The old command.}
% with bad spacing.
% \end{minipage}
% \hfill 
% \begin{minipage}{5.6cm}
% \begin{verbatim}
%This is a note
%\footnote{ 
%The new command.}
%with good spacing.
% \end{verbatim}
% \vspace{-4ex} 
% This is a note 
% \footnote{ 
% The new command.}
% with good spacing.
% \end{minipage}
%
% \medskip
% \DescribeMacro{\footnotespace} \DescribeMacro{\footenoteindent}
% Like the old one, the new "\footnote" command can take an optional argument
% to force the number of the note.
% Likewise, we have always customization macros 
% "\footnotesize", "\footnotesep", "\footnoterule",
% but two new macros have been added to manage spacing:
% "\footnotespace" produces the space before the note call symbol
% and "\footnoteindent" produces the space at the beginning of the footnote text.
% For instance, with "\renewcommand{\footnotespace}{\,}" \\
% and "\renewcommand{\footnoteindent}{\enskip}"
% \footnote{\texttt{\bslash enskip} is equivalent to \texttt{\bslash hspace\{0.5em\}}.}
% we get:
% \renewcommand{\footnotespace}{\,}
% \renewcommand{\footnoteindent}{\enskip}
%
% \begin{center}
% \begin{minipage}{7cm}
% This is a note \footnote{en dash spacing at the beginning of the note.}  
% with particular space settings.
% \end{minipage}
% \end{center}
% \renewcommand{\footnotespace}{}
% \renewcommand{\footnoteindent}{}
% 
% \hypertarget{vstrut}{}
% \DescribeMacro{\vstrut} 
% "\vstrut"\oarg{depth}\marg{height} produces a strut with variable height or depth,
% in order to increase the line's height (above the base line) or depth 
% (below the base line, optional);
% this command can be used in a text line, a table, a list, a formula, etc.
% If the values of \meta{height} and \meta{depth} are inferior to the height and depth
% of the current line, the command has no effect.
% Here are some examples.
% \setlength{\juxtopskip}{0pt}\setlength{\juxbottomskip}{0pt}
% \begin{juxtapose}
% \begin{verbatim}
%\[\frac{\sqrt{0.5p}}{10} = 
%\frac{\sqrt{\vstrut{1.7ex} 0.5p}}{10}\]
% \end{verbatim}
% \otherside
% \[\frac{\sqrt{0.5p}}{10} = \frac{\sqrt{\vstrut{1.7ex} 0.5p}}{10}\]
% \end{juxtapose}
% \noindent"\fbox{\vstrut{2ex}$\sigma(X)=1$}" gives
% \fbox{\vstrut{2ex}$\sigma(X)=1$}
% better than \fbox{$\sigma(X)=1$}.
% 
% \medskip
% \noindent
% The height adjustment is done by trial and error.
% We could also have used a vertical phantom box;
% for example in the previous square root, we get a good result with "\vphantom{\bar{t}}",
% but it's not obvious to know what to put in the phantom box,
% moreover, "\vstrut" allows a finer tuning.
%
% In a table,
% "\renewcommand{\arraystretch}"\marg{stretch}
% allows to increase the height of the rows but this command
% has a global effect, whereas "\vstrut" allows to adjust properly the height of each row, 
% as in the following table:
% \[  
% \begin{array}{|c|}
% \hline
% \text{bad}\\
% \hline
% \displaystyle \lim_{\substack{x \to 1\\x>1}} \ln\left(\dfrac{x^2}{x-1}\right) \\
% \hline
% \dfrac{a}{b} \\
% \hline
% \displaystyle \int_{1}^{X} \frac{1}{t}\, \mathrm{d}t  \\
% \hline
% \end{array}
% \qquad
% \begin{array}{|c|c|}
% \hline
% \multicolumn{2}{|c|}{\text{good}}\\
% \hline
% \displaystyle\lim_{\substack{x \to 1\\x>1}} \ln\left(\dfrac{x^2}{x-1}\right)\vstrut{3.8ex}
% & \mbox{obtained with } "\vstrut{3.8ex}" \\
% \hline
% \dfrac{a}{b} \vstrut[2ex]{3ex} & "\vstrut[2ex]{3ex}" \\
% \hline
% \displaystyle\int_{1}^{X} \frac{1}{t} \, \mathrm{d} t \vstrut[2.5ex]{4.2ex}
% & "\vstrut[2.5ex]{4.2ex}" \\
% \hline
% \end{array}
%\]
% However, for tables, we have the \textsf{arraycols} package~\cite{ARCOL},
% based on \textsf{cellspace}~\cite{CELLSP}, which allows to adjust 
% row heights automatically. Nevertheless, "\vstrut" can be useful for fine adjustments. 
%
% In a text line "\vstrut" can be used to increase line space, better than "\vspace".
%
% \hypertarget{indent}{}
% \medskip
% \DescribeMacro{\indent} 
% The command "\setlength{\parindent}{0cm}" allow to eliminate any indentation of lines
% at the beginning of every paragraph. 
% But in this case, the "\indent" command does not work anymore
% if we want exceptional indentation of a particular paragraph.
% So, the initial length of "\parindent" has been saved in "\parindentlength"
% \DescribeMacro{\parindentlength} 
% and the command "\indent" has been redefined to still allow indentation
% of length "\parindentlength".
%
% \hypertarget{indentblock}{}
% \medskip
% \DescribeEnv{indentblock}
% The \texttt{indentblock} environment allows indentation of a whole block of lines.
% It has an optional argument which is the length of indentation
% (set by default to "\parindentlength").
% The following lyrics have been indented (and typeset in italic shape) with
% "\begin{indentblock}\itshape" and stanzas 2 and 4 have been affected by
% an additional indentation with "\begin{indentblock}[3em]".
%
% \smallskip
% \begin{indentblock}\itshape
% Overhead the albatross hangs motionless upon the air \\
% And deep beneath the rolling waves in labyrinths of coral caves \\
% The echo of a distant time comes willowing across the sand \\
% And everything is green and submarine 
% \begin{indentblock}[3em]
%    And no one showed us to the land \\
%    And no one knows the where's or why's \\
%    But something stirs and something tries \\
%    Starts to climb towards the light
% \end{indentblock}
% \noindent
% Strangers passing in the street \\
% By chance two separate glances meet \\
% And I am you and what I see is me \\
% And do I take you by the hand \\
% And lead you through the land \\
% And help me understand the best I can?
% \begin{indentblock}[3em]
%    And no one calls us to move on \\
%    And no one forces down our eyes \\
%    No one speaks and no one tries \\
%    No one flies around the sun
% \end{indentblock}
% \end{indentblock}
% 
% \hypertarget{compactlist}{}
% \DescribeEnv{compactlist}
% As its name tells it, the "compactlist" environment allows to create
% a ``compact'' list, \ie without vertical space neither above nor between items.
% As for lists in \LaTeX, items are generated by the "\item" command.
% The environment has an optional argument: "\begin{compactlist}"\oarg{symbol}.
% 
% \hypertarget{symbols}{}
% \medskip
% \DescribeMacro{\bul}\DescribeMacro{\dash}\DescribeMacro{\ddash}\DescribeMacro{\aster}
% The default item symbol is "\textbullet", but can be changed.
% We provide aliases for several symbols commonly used in lists:
% "\bul" \bul\ (alias for "\textbullet"), "\dash" \dash\ (alias for "\textendash"), 
% "\ddash" \ddash\ (alias for "\textemdash"), 
% "\aster" \aster\ ("alias for \textasteriskcentered").
%
% \smallskip
% \DescribeEnv{[pifont]}
% \DescribeMacro{\hand}\DescribeMacro{\checksymb}\DescribeMacro{\arrowsymb}
% Some other common symbols can be found in the \textsf{pifont} package~\cite{PIFONT}.
% Therefore \textsf{spacingtricks} has a \texttt{pifont} option,
% that loads this package and creates the appropriate aliases:
% "\hand" \hand for "\ding{43}", "\checksymb" \checksymb for "\ding{51}"
% and "\arrowsymb" \arrowsymb for "\ding{226}".
%
% \medskip \noindent
% The following example is produced by "\begin{compactlist}[\checksymb]":
% \begin{compactlist}[\checksymb]
% \item First item.
% \item Second item.
% \item Third item.
% \end{compactlist}
% \hand These aliases can also be used directly in some text.
% The symbol is followed by a space if there is no punctuation character 
% just after it (thanks to the 
% macro \texttt{xspace} from the \textsf{xspace} package~\cite{XSP}).
% Use "\"\meta{symbol}"\unskip" if you want to remove this space.
%
% \smallskip
% \DescribeMacro{\compactlistindent}
% Indentation length is set by "\compactlistindent" (fixed at 0.5\,em by default) 
% and can be modified with "\setlength".
% Notice that there are several other ways to construct a compact list in particular
% with the \texttt{noitemsep} key of the \textsf{enumitem} package~\cite{ENUM}.
%
% \medskip
% \DescribeEnv{dinglist}
% The \textsf{pifont} package has also a list environment "\begin{dinglist}"\marg{number}
% to typeset a list with normal spacing, using the "\ding"\marg{number} symbol
% for each "\item" (instead of using "\item[\ding"\marg{number}"]"). 
% So "\begin{dinglist}{226}" yields:
% \begin{dinglist}{51}
% \item The first item in the list.
% \item The second item in the list.
% \item The third item in the list.
% \end{dinglist}
%
% \hypertarget{ie-eg}{}
% \medskip
% \DescribeMacro{\ie} \DescribeMacro{\eg}
% In English, at the end of a sentence, the point is followed by an em space
% which is larger than an inter-word space.
% We provide the "\ie" (\textit{id est}) and "\eg" (\textit{exempli gratia}) macros,
% suggested in The \LaTeX\ Companion \cite{COMP},
% to get correct spacing after these abbreviations \eg here.
% In American typography, a comma is often placed after these abbreviations,
% what we can get with "\ie,"
% on the other hand, some authors prefer to typeset \textit{\ie} in italic shape,
% which is always possible with "\textit{\ie}". 
%
% \hypertarget{dualboxes}{}
% \medskip
% \DescribeMacro{\dualboxes}
% Several packages intend to typeset text around a figure or a table,
% but some of them need to give the width of the box containing the figure or the table.
% We provide here another approach with the macro
% "\dualboxes"\oarg{pos}\marg{left}\marg{right},
% which places two boxes, \meta{left} and \meta{right}, side by side.
% These boxes can contain figures, tables, one small line text, 
% parbox text, \texttt{minipage} environments
% (for several paragraphs and lists), etc.
% The optional \meta{pos} parameter sets the vertical level on which the boxes are aligned:
% a number between 0 (bottom) and 1 (top, default value).
%
% Here is a first example in which we have adjusted  the postion
% of the boxes vertically, with "\dualboxes[0.6]".
%
% \def\myfigure{%
% \begin{tikzpicture}[scale=0.6]\tiny 
%     \draw[->] (-4.5,0) -- (4.5,0);
%     \draw[->] (0,-2) -- (0,1.5);
%     \foreach \x in {-4,...,4} {\draw (\x,0.1cm) -- (\x,-0.1cm) node[below] {$\x$};}
%     \foreach \y in {-1,1} {\draw (0.1cm,\y) -- (-0.1cm,\y) node[left] {$\y$};}
%     \draw[domain=-4.5:4.5,samples=100,color=red] plot ({\x},{2*\x/(exp(\x)-\x)});
% \end{tikzpicture}}
%
% \def\mytable{
%     $\begin{array}{|*{6}{c|}} \hline
%         x    & -2    & -1    & 0 & 1    & 2    \\ \hline
%         f(x) & -1,87 & -1,46 & 0 & 1,16 & 0,74 \\ \hline
%     \end{array}$
% }
%
% \medskip
% \dualboxes[0.6]{\scriptsize \mytable}{\myfigure}
%
% \noindent
% The horizontal space is equally shared between left margin, inter-box space 
% and right margin.
% 
% \medskip
% In the following example boxes are aligned by top and
% the right box has been shifted back (left) from 3\,cm
% to make an overlapping with the left one, what \textsf{picins} cannot do. 
% 
% \dualboxes{\scriptsize \mytable}{\mbox{} \hspace{-3cm} \myfigure}
% \begin{verbatim}
% \dualboxes{\scriptsize
%     $\begin{array}{|*{6}{c|}} \hline
%         x    & -2    & -1    & 0 & 1    & 2    \\ \hline
%         f(x) & -1,87 & -1,46 & 0 & 1,16 & 0,74 \\ \hline
%     \end{array}$
% }{\mbox{} \hspace{-3cm}
%     \begin{tikzpicture}[scale=0.6]\tiny
%         \draw[->] (-4.5,0) -- (4.5,0);
%         \draw[->] (0,-2) -- (0,1.5);
%         \foreach \x in {-4,...,4} {
%             \draw (\x,0.1cm) -- (\x,-0.1cm) node[below] {$\x$};}
%         \foreach \y in {-1,1} {
%             \draw (0.1cm,\y) -- (-0.1cm,\y) node[left] {$\y$};}
%         \draw[domain=-4.5:4.5,samples=100,color=red] 
%             plot ({\x},{2*\x/(exp(\x)-\x)});
%     \end{tikzpicture}
% }
% \end{verbatim}
%
% \DescribeMacro{\dualboxes*}
% This command has a starred version that eliminates space before the first box
% and after the second one, but not between them:
% "\dualboxes*"\oarg{pos}\marg{left}\marg{right}.
%
% \smallskip
% \dualboxes*[0.6]{\parbox{6.5cm}{
%     In practice, \texttt{\bslash dualboxes} is suitable for boxes in which 
%     you put figures or tables or small one line text.
%     For longer text, this one must be nested in a paragraph box, \eg 
%     here we used \texttt{\bslash parbox\{6.5cm\}\{...\}}.
%     If you want several paragraphs, a list or a mathematical displayed formula,
%     then you have to put them in a \texttt{minipage} environment.}
% }{\myfigure}
%
% \medskip
% Let us indicate that it is unfortunately not possible to use \texttt{verbatim} environments
% (nor the in-line \texttt{\bslash verb} command)
% within "\dualboxes" arguments,
% as well as it is not possible for footnotes or margin notes.  
%
% \medskip
% For putting two figures side by side, or a table and a figure, "\dualboxes" is perfect.
% But for text around a figure, some other package may be more efficient.
% Les us mention first \textsf{wrapfig}~\cite{WRAPFIG}, one of the easiest, but text must
% contain in a single paragraph (like above), without list or you have to place it in
% a \texttt{minipage} environment.
%
% More sophisticated is the \textsf{picins} package~\cite{PICINS},
% cited in The \LaTeX\ Companion~\cite{COMP}.
% Unlike most others, it can be used with lists,
% nevertheless vertical positioning can be tricky
% and it doesn't belong to common distributions \TeX{}\,Live or MiK\TeX.
% A last one we mention is \textsf{picinpar}~\cite{PICINPAR} in which
% text can begin after the first line and can flow to the two side of the figure;
% it allows several paragraphs but neither lists, nor verbatim text.
%
% \hypertarget{juxtapose}{}
% \medskip
% \DescribeEnv{juxtapose}
% As a very interesting alternative, we present the powerful \texttt{juxtapose} environment,
% written by Christian Obrecht in the \texttt{fiche.cls class} file,
% which is part of the \textsf{mafr} distribution~\cite{MAFR}.
% We made small improvements, among others to work correctly with lists and
% get customization of some lengths:
% \DescribeMacro{\juxtopskip}\DescribeMacro{\juxbottomskip}
% \DescribeMacro{\juxsepspace}
% top and bottom lengths are set by default to "\smallskipamount" 
% and separation space is set to 1.5\,em.
% For spacing above or below the environment, if the default length doesn't fit well,
% you can add a "\bigskip" or a "\vspace"\marg{dimen} for example,
% or at worst redefine the length "\juxtopskip" and "\juxbottomskip".
% \begin{juxtapose}
%     In this example the environment begins here.
%     \texttt{juxtapose} can deal with figures, tables, but also:
%     \begin{compactlist}
%         \item verbatim text: "\mytestmacro",
%         \item text with several paragraphs,
%         \item lists, like here (a compact list),
%         \item displayed mathematics as shown on the right side,
%     \end{compactlist} 
%     without the need of \texttt{multipage} environments.

% The two boxes are aligned by their center, but
% unlike "\dualboxes", you cannot adjust vertical positioning,
% except using "\vspace".\smallskip
% 
% \otherside 
%     \myfigure
%     \[ f(x) = \frac{2x}{\mathrm{e}^x-x} \]
%     This is the last line of the environment.
% \end{juxtapose}
%
% Here begins the following text. The syntax of \texttt{juxtapose} is simple: 
% \begin{center}
% "\begin{juxtapose} ... \otherside ... \end{juxtapose}"
% \end{center}
% It has an optional argument "\begin{juxtapose}"\oarg{leftratio}
% where \meta{leftratio} is the width ratio of the left side relatively to "\textwidth"
% (the default value is "0.5" which means "0.5\textwidth"). 
%
% Paragraphs are indented inside each side, except the first one,
% because for a figure, there's no need to shift it to the right
% (from indent length) and otherwise the user may forgot to 
% put "\noindent" before the figure.
% If you still want to indent the first paragraph use "\indent".
% For horizontal alignment inside a box, you can use "\centering" or "\flushright"
% (useful for a figure).
% If you want a global indentation of the first (or the second) box, you
% can put it in an \texttt{indentblock} environment, it works fine!
%
% \medskip
% One may ask why not using multi column environments instead.
% In the classic \textsf{multicol} environment you cannot choose 
% horizontally unbalanced
% columns and you cannot choose where to pass to the other column.
%
% Some nice packages improve \textsf{multicols}, \eg \textsf{vwcol}~\cite{VWCOL} in which
% you can fix on the columns width, but unfortunately it doesn't accept
% verbatim text, and doesn't manage correctly lists and figures like above.
%
% Let us mention \textsf{paracol}~\cite{PARA} and \textsf{reledpar}~\cite{RELP},
% which are intended to typeset two column of text in parallel, 
% useful for translation or critical edition of text.
% They work fine with lists, figures, verbatim text, and also footnotes and margin notes,
% but it is not immediate to obtain just a chosen vertical positioning of two boxes.
% They have synchronization mechanisms, convenient for text, but
% not when you place two figures side by side.
% Besides they are a bit oversized for our need. They don't have the same purpose.
% So we can hope \texttt{juxtapose} or "\dualboxes" are useful.
%
% \StopEventually{}
%
% \section{Implementation}
%    \begin{macrocode}
\newif\ifspacingtricks@pifont
\DeclareOption{pifont}{\spacingtricks@pifonttrue}
\ProcessOptions \relax

\RequirePackage{ifthen}
\RequirePackage{calc}
\RequirePackage{setspace}
\RequirePackage{xspace}
\RequirePackage{centeredline}
\ifspacingtricks@pifont \RequirePackage{pifont} \fi

\newcommand*{\centered}[1]{{\setlength{\parskip}{0pt}\par\noindent\hfill
        #1\hfill\mbox{}}}
%    \end{macrocode}
% The double braces are necessary here to ensure that the "\parskip" modification applies
% locally within the command and not globally to the rest of the document. 
% \smallskip
%    \begin{macrocode}
\newcommand{\footnotespace}{}
\newcommand{\footnoteindent}{}
\let\footnt\footnote
\renewcommand{\footnote}[2][]{\unskip\footnotespace%
    \ifthenelse{\equal{#1}{}}{
        \unskip\footnt{\footnoteindent\ignorespaces #2}
    }{
        \unskip\footnt[#1]{\footnoteindent\ignorespaces #2}
    }\unskip
}
%    \end{macrocode}
% "\unskip" eliminates undesirable spaces before and "\ignorespaces" after.
% \smallskip
%    \begin{macrocode}
\newlength{\strutheight}
\newcommand*{\vstrut}[2][0pt]{%
    \setlength{\strutheight}{#2}%
    \addtolength{\strutheight}{#1}%
    \unskip
    \ensuremath{\rule[-#1]{0pt}{\strutheight}}%
    \ignorespaces%
}

\newlength{\parindentlength}
\setlength{\parindentlength}{\parindent}
\renewcommand{\indent}{\hspace{\parindentlength}}

\newenvironment*{indentblock}[1][\parindentlength]{
    \begin{list}{}{% 
        \setlength{\leftmargin}{#1}
        \setlength{\itemsep}{0pt}
        \setlength{\topsep}{0pt} % previously 1ex
        \setlength{\partopsep}{0pt}
    }
    \item[]
}{\end{list}}

\newlength{\compactlistindent}
\setlength{\compactlistindent}{0.5em}
\newenvironment*{compactlist}[1][\textbullet]{
    \par % sometimes necessary
    \begin{list}{#1\unskip}{% \unskip gobbles space created by \xspace
        \setlength{\itemsep}{0pt}
        \setlength{\parsep}{0pt}
        \setlength{\topsep}{0ex}
        \setlength{\partopsep}{0pt}
        \setlength{\labelwidth}{1em}
        \setlength{\leftmargin}{\labelwidth}
        \addtolength{\leftmargin}{\labelsep}
        \addtolength{\leftmargin}{\compactlistindent}
    }
}{\end{list}}

\providecommand{\bul}{\textbullet\xspace}
\providecommand{\dash}{\textendash\xspace}
\providecommand{\ddash}{\textemdash\xspace}
\providecommand{\aster}{\textasteriskcentered\xspace}
%    \end{macrocode}
% The command "\asterisk" already exists in the \textsf{mathabx} package (for math mode only).\\
% The following macros need the \textsf{pifont} package.
% \smallskip
%    \begin{macrocode}
\ifspacingtricks@pifont
    \providecommand{\hand}{\ding{43}\xspace}
    \providecommand{\checksymb}{\ding{51}\xspace}
    \providecommand{\arrowsymb}{\ding{226}\xspace}
\fi

\providecommand{\ie}{i.e.\@\xspace}
\providecommand{\eg}{e.g.\@\xspace}

\newcommand{\@@dualboxes}[3][1]{
    \par\noindent
    \raisebox{\depth-#1\totalheight}{#2} \hfill % needs calc
    \raisebox{\depth-#1\totalheight}{#3} \smallskip
}
\newcommand{\@dualboxes}[3][1]{
    \par\noindent \hfill
    \raisebox{\depth-#1\totalheight}{#2} \hfill
    \raisebox{\depth-#1\totalheight}{#3} \hfill\mbox{}\smallskip
}
\newcommand{\dualboxes}{\@ifstar{\@@dualboxes}{\@dualboxes}}

%    \end{macrocode}
%
% The following macro has been found in the \texttt{fiche.cls} file,
% distributed with the \textsf{mafr} package by Christian Obrecht~\cite{MAFR}.
% It had some tiny bugs in spacing.
% I just made small changes: adding some lengths parameters and the "\linewidth"
% instruction (without whom, lists in the first side send the second side out of the page).
%    \begin{macrocode}
\newlength\juxtopskip
\setlength\juxtopskip{\smallskipamount}
\newlength\juxbottomskip
\setlength\juxbottomskip{\smallskipamount}
\newlength\juxsepspace
\setlength\juxsepspace{1.5em}
\newlength\side@width

\newenvironment{juxtapose}[1][0.5]{% left side ratio
    \def\otherside{\egroup % internal function remembers \side@width
        \@tempdima=\side@width
        \side@width=\textwidth
        \advance\side@width by -\@tempdima
        \advance\side@width by -\juxsepspace
        \hskip\juxsepspace
        \linewidth=\side@width % for lists environments
        \vcenter\bgroup\hsize=\side@width\noindent % \ignorespaces useless
        }
    \side@width=#1\textwidth
    \advance\side@width by -0.5\juxsepspace
    \linewidth=\side@width % for lists environments
    \par\vskip\juxtopskip%
    \hbox\bgroup\begin{math}
    \vcenter\bgroup\hsize=\side@width\noindent\ignorespaces
    }{\egroup\end{math}\egroup\vskip\juxbottomskip}

%    \end{macrocode}
%
% \medskip
% \begin{thebibliography}{17}
% \begin{raggedright}
% \bibitem{SETSP} \emph{The \textsf{setspace} Package}, Robin Fairbairns, Geoffrey Tobin,
% CTAN, v9.7b 2022/12/04.
% \bibitem{XSP} \emph{The \textsf{xspace} package}, David Carlisle, Morten Høgholm, 
% CTAN v1.13 2014/10/28.
% \bibitem{CENTER} \emph{\textsf{centeredline} -- A macro for centering lines}, Jean-François
% Burnol, CTAN, v1.2 2022/10/10.
% \bibitem{MAFR} \emph{La distribution \textsf{mafr}}, Christian Obrecht, 
% CTAN, v1.0 17/09/2006.
% \bibitem{ARCOL} \emph{The \textsf{arraycols} package}, Antoine Missier, CTAN, 
% v1.2 2021/09/20.
% \bibitem{MSMATH} \emph{\textsf{mismath} -- Miscellaneous mathematical macros}, 
% Antoine Missier, CTAN, v2.5 2023/02/24.
% \bibitem{MKCELL} \emph{The \textsf{makecell} package}, Olga Lapko, CTAN, v0.1e 2009/08/03.
% \bibitem{CELLSP} \emph{The \textsf{cellspace} package}, Josselin Noirel, CTAN, 
% v1.9.0 2022/01/04.
% \bibitem{PIFONT} \emph{\textsf{pifont} -- Using common PostScript fonts with \LaTeX}, 
% Walter Schmidt, CTAN, v9.3 2020/03/25.
% \bibitem{ENUM} \emph{Customizing lists with the \textsf{enumitem} package}, Javier Bezos, 
% CTAN, v3.9 2019/06/20.
% \bibitem{WRAPFIG} \emph{The \textsf{wrapfig} package}, Donald Arseneau, CTAN, 
% v3.6 2003/01/31.
% \bibitem{PICINS} \emph{Bilder in \LaTeX -Dokumenten -- PicIns-Benutzerhandbuch},
% Joachim Bleser, Edmund Lang, CTAN, v3.0 sept. 1992.
% \bibitem{PICINPAR} \emph{The \textsf{picinpar} package}, Friedhelm Sowa, Stefan Blochwitz, 
% CTAN, v1.3 2022/11/25.
% \bibitem{VWCOL} \emph{The \textsf{vwcol} package}, Will Robertson, CTAN, v0.2 2015/02/10.
% \bibitem{PARA} \emph{Package \textsf{paracol}: Yet Another Multi-Column Package 
% to Typeset Columns in Parallel}, Hiroshi Nakashima, CTAN, v1.35 2018/12/31. 
% \bibitem{RELP} \emph{Parallel typesetting for critical editions:
% the \textsf{reledpar} package}, Maïeul Rouquette, Peter Wilson, Herries Press, CTAN,
% 2.25.3 2022/04/22.
% \bibitem{COMP} \emph{The \LaTeX\ Companion}. Frank Mittelbach, Michel Goossens, 
% Johannes Braams, David Carlisle, Chris Rowley, 2nd edition, Pearson Education, 2004.
% \end{raggedright}
% \end{thebibliography}
%
% \Finale
\endinput
