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% deleq.dtx Version 4.41b, June 5, 1998
% (c) 1994-98 by Mats Dahlgren (matsd@sssk.se)
%
% Please see the information in file `deleq.ins' on how you
% may use and (re-)distribute this file. Run LaTeX on the file
% `deleq.ins' to get a .sty-file, instructions, and an example.
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% This file may NOT be distributed if not accompanied by 'deleq.ins'.
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% \def\filename{deleq.dtx}
% \def\fileversion{4.41a}
% \def\filedate{1997/07/07}\def\docdate{1997/06/05}
% \MakeShortVerb{\|}
% \date{\docdate}
% \title{\textsf{deleq} -- a \LaTeX{} Macro for Partial
% Numbering of Equations\thanks{This document describes
% \textsf{deleq} version \fileversion , last revised \docdate}}
% \author{Mats Dahlgren\footnote{Email:\ \texttt{matsd@sssk.se}\ \ \
% Web:\ \texttt{http://www.homenet.se/matsd/}}}
% \begin{document}
% \maketitle
% \begin{abstract}
% To enable a more flexible equation numbering, especially
% ``partial'' equation numbers (`3a', `3b' \textit{etc.}),
% the \textsf{deleq} package has been developed. It can produce
% partial equation numbers intermixed with ordinary
% equation numbers also in an |eqnarray|-like environment,
% the intermixing can occur within one environment.
% References to a partially numbered equation can be both the
% complete equation number (`3b') or only the main equation
% number (`3').
% Furthermore, equation numbers can be recycled without
% disturbing the ordinary equation numbers. The
% package also provides commands for putting commentatory
% text in an |eqnarray| environment.
% Both standard \LaTeX{} class options
% |leqno| and |fleqn|\footnote{Not all commands of
% \textsf{deleq} work with the \texttt{fleqn} option.}
% work with \textsf{deleq}.\\
% \small This file and the package:\
% Copyright \copyright\ 1994-1998 by Mats Dahlgren.
% All rights reserved.
% \end{abstract}
%
% \section{Introduction}
% \textsf{deleq} is a \LaTeX{} package which makes partial
% numbering of equations possible. It is meant to be used
% when numbering such as 3a, 3b, \textit{etc.} is desired.
% The default is to give an equation number like `3a'
% without period and with the `a' typeset in roman font.
% It can be used in |article| as well as |book| and
% |report| document classes. The examples given below are
% valid for the |article| class. \textsf{deleq} is fully
% compatible with the |leqno| documentclass option and
% almost fully with the |fleqn| class option.
% Equations can be numbered either 3, 3a, 3b, $\ldots$, or
% 2, 3a, 3b, $\ldots$. Also, equation numbers within
% |eqnarray|-like environments can be numbered 3, 3a, 3b,
% $\ldots$ or starting at 3a, which can follow both after
% equation 2b or 3. An |eqnarray|-like environment can have
% its first equation numbered 3b if the nearest previous
% equation is 3a. Within one |eqnarray|-like environment,
% equations can be numbered 3a, 3b, 4, 4a, 4b, 5a, 5b,
% \textit{etc.}, and also not numbered lines are possible
% (`|\nonumber|' works with some limitations).
% Furthermore, equation numbers can
% be ``recycled''. If equation 3 is repeated after
% equation 8, it can still have the numbering set to 3,
% and be followed by (a new) equation 9. ``Recycled''
% equation numbers can receive partial numbers (3a, 3b,
% $\ldots$); partially numbered equations can also be
% ``recycled'' (but at this stage, the latter can not
% receive new partial numbers neatly, it will come out
% like `3ba' if eqution 3b is the ``recycled'' equation).
% Two commands are supplied which enable the user to write
% commentary texts in |eqnarray|-like environments without
% interfering with the alignment.
%
% This userguide is also available in \texttt{.pdf}-format
% on the internet. It is found from my \LaTeX\ web page:
% \texttt{http://www.homenet.se/matsd/latex/}
%
% \subsection{History}
% |deleq.sty| was originally written for \LaTeX{} 2.09,
% and contained several commands which became obsolete
% with the introduction of \LaTeXe. These commands have
% been removed. The first release for \LaTeXe{} was v.4.0,
% of Oct.~14, 1994. The December 1994 release
% (v.4.1, Dec.~27, 1994) was the first which was compatible with the
% |docstrip| utility of Johannes Braams, Denys Duchier and
% Frank Mittelbach. In release v.4.2 new
% abilities to reference entire |deqarr| and |ddeqar|
% environments and enhanced abilities for recycled
% equation numbers were introduced.
% Also in \textsf{deleq} v.4.2 this
% documentation was revised and some internal commands
% compacted.
% A previous release, v.4.3, was made nessecary
% because the changed handeling of arguments in connection
% with the options in \LaTeXe{} of 1995/06/01.
% In release v.4.4, compatibility with the \LaTeX{}
% class option |fleqn| was
% introduced.\footnote{\texttt{fleqn} incompatibility was
% pointed out by Peter Kruijt (\texttt{peterk@wfw.wtb.tue.nl})}
% In v.4.41 only some changes to the documentation have been introduced.
%
% \textsf{deleq} version 4.41 has been tested with \LaTeXe{}
% of 1997/06/01 running \TeX{} 3.14159 in MiK\TeX{} 1.07
% under Windows~95. Please send bug reports (see below),
% corrections, additions, suggestions, \textit{etc.}\ to
% me at \texttt{matsd@sssk.se}.
% Version 3.02 is the last
% (non-supported) version for \LaTeX{} 2.09. (Command names
% are a mixture of \LaTeX , Swedish and a bit of the
% author's fantasy$\ldots$)
%
% \subsection{Known Problems}
% \begin{itemize}
% \item \DescribeMacro{\eqreqno} \DescribeMacro{\deqreqno}
% \DescribeMacro{\ddeqreqno} \DescribeEnv{deqarr}
% \DescribeEnv{ddeqar} \DescribeMacro{\jotbaseline}
% When using |\eqreqno|, |\deqreqno|, and |\ddeqreqno|
% on the last line in a |deqarr|, |ddeqar|, |eqnarray|, or
% |eqnarray*|, there will be an extra blank line with an
% equation number (not in the |*| form) at the end of the
% environment. To avoid this problem, use\\
% | \eqreqno[-\jotbaseline]{FOO} \nonumber|\\
% instead of
% |\eqreqno{FOO}| (the analogues for |\deqreqno| and
% |\ddeqreqno| are obvious).
% \end{itemize}
%
% \section{Userguide}
% \subsection{Requirements}
% The file |deleq.sty| must be available in the user's
% |TEXINPUTS| directories.
% It requires \LaTeXe{} of 1996/12/01 (or newer).
%
% \subsection{Usage}
% The package is included by stating\\
% | \usepackage{deleq}| \\
% In the document preamble.
% The documentclass option |leqno| is fully supported,
% and the option |fleqn| is recognized by the environments
% defined in \textsf{deleq}.
% Other class or package options do not have any effect on
% \textsf{deleq}.
%
% \subsection{Environments}
% The package defines the following five environments:
% \begin{description}
% \item{\texttt{deqn}} \DescribeEnv{deqn}
% is an equation environment for automatic
% numbering of the first equation of type `3a';
% \item{\texttt{ddeqn}} \DescribeEnv{ddeqn}
% is an equation used for automatic numbering
% of the equations following the one in |deqn|, see also details
% below;
% \item{\texttt{deqarr}} \DescribeEnv{deqarr}
% is an environment for automatic partial equation
% numbering in |eqnarray|-like environment with
% |deqn| functionality for the first equation;
% \item{\texttt{ddeqar}} \DescribeEnv{ddeqar}
% similar to |deqarr| environment, but
% with |ddeqn| behaviour for the first equation, see details below;
% \item{\texttt{deqrarr}} \DescribeEnv{deqrarr}
% this is an `|eqnarray|'-like environment
% specially designed for recycled equation numbers.
% \end{description}
%
% \subsection{Commands}
% The package defines the following fourteen user commands:\\
% \hspace*{5mm}|\nydeqno|\\
% \hspace*{5mm}|\heqno|\\
% \hspace*{5mm}|\reqno{FOO}|\\
% \hspace*{5mm}|\rndeqno{FOO}|\\
% \hspace*{5mm}|\rdeqno{FOO}|\\
% \hspace*{5mm}|\eqreqno[|\textit{len}|]{FOO}|\\
% \hspace*{5mm}|\deqreqno[|\textit{len}|]{FOO}|\\
% \hspace*{5mm}|\ddeqreqno[|\textit{len}|]{FOO}|\\
% \hspace*{5mm}|\arrlabel{FOO}|\\
% \hspace*{5mm}|\where|\\
% \hspace*{5mm}|\rem{|\textit{text}|}|\\
% \hspace*{5mm}|\nydeleqno|\\
% \hspace*{5mm}|\deleqno|\\
% \hspace*{5mm}|\jotbaseline|\\
%
% \subsection{Notice}
% \begin{enumerate}
% \item
% \DescribeMacro{\nydeqno} \DescribeMacro{\heqno}
% \DescribeMacro{\arrlabel} \DescribeEnv{deqarr}
% \DescribeEnv{ddeqarr}
% The use of |\arrlabel| may give unexpected results if
% any of the commands |\nydeqno| or |\heqno| is used in the
% same |deqarr| or |ddeqar| environment.
% \item If you use |\nydeqno|,
% |\heqno|, |\reqno|, |\rndeqno|, |\rdeqno|,
% |\deqreqno|, |\ddeqreqno|, |\nydeleqno|, or |\deleqno| in
% combination with |\label{FOO}|, |\label{FOO}| should
% appear after the \textsf{deleq}-command;
% \item If you change the appearance of equation numbers
% (\textit{e.g.}\ use
% `[2]' instead of `(2)'), \textsf{deleq}'s commands may not typeset
% equations with partial numbers like your ordinary
% equations.
% \item The class option |fleqn| is not recognized by the
% commands |\reqno|, |\rndeqno|, |\rdeqno|, |\nydeleqno|, and
% |\deleqno|.
% \end{enumerate}
%
% \section{Syntax}
% Here follows a more detailed description of the
% different environments and commands.
% \begin{description}
% \item{|\begin{deqn} ... \end{deqn}|} \DescribeEnv{deqn} \\
% Typesets an equation just like
% |\begin{equation} ... \end{equation}| does, but gives it
% a number such as `3a' instead of `3' (always `a'). It
% steps the main equation counter.
%
% \item{|\begin{ddeqn} ... \end{ddeqn}|} \DescribeEnv{ddeqn} \\
% Typesets an equation just like
% |\begin{equation} ... \end{equation}| does, but gives it
% a number such as `3b', `3c', $\ldots$ instead of `3',
% `4', $\ldots$ when following after another partially
% numbered equation. When following after an ordinarily
% numbered equation (`3') it gives a partial equation
% number with the last used ordinary equation number,
% \textit{e.g.}\ `3a'. Can be made to produce the result
% of |deqn| environment by the use of |\nydeqno| (see
% below). |ddeqn| does not step the main equation counter.
%
% \item{|\begin{deqarr} ... \end{deqarr}|} \DescribeEnv{deqarr} \\
% Typesets an equation array just like
% |\begin{eqnarray} ... \end{eqnarray}| does, but gives
% the first numbered equation a number like `3a' instead
% of `3' (always `a'), and the following `3b', `3c'
% \textit{etc.} It steps the main equation counter.
% The |\nonumber| command works just like
% in the |eqnarray| environment on the partial equation
% counter. Thus, if you use |\nonumber| on all lines in an
% |deqarr| environment (or on all lines before or between
% |\heqno| or |\nydeleqno|) the equation numbering in your
% document will be incorrect. There is no warning issued by
% \LaTeX{} if this happends. If you want blank lines and
% then a |\heqno|'ed equation followed by partially numbered
% equations, use the |ddeqar| environment instead. The same
% is true for |\nydeqno|'ed equations.
%
% \item{|\begin{ddeqar} ... \end{ddeqar}|} \DescribeEnv{ddeqar} \\
% Typesets an equation array just like
% |\begin{eqnarray} ... \end{eqnarray}| does, but gives
% the equation numbers such as `3a' if following after an
% equation numbered `3' (ordinary equation number) and
% numbers such as `3c' if following after a partially
% numbered equation `3b'. Can be made to produce the
% result of |deqarr| environment by the use of |\nydeqno|.
% |ddeqar| does not step the main equation counter.
% The |\nonumber| command works like in the
% |deqarr| environment.
%
% \item{|\begin{deqrarr} ... \end{deqrarr}|} \DescribeEnv{deqrarr} \\
% This environment is meant to host recycled equations and has
% |eqnarray| structure. By default, it issues no equation
% number at all on a line which ends with |\\|. The use of
% |\label{FOO}| within |deqrarr| returns the present partial
% equation number of recycled equations (just like with
% |\rndeqno| and |\rdeqno|). Note that neither |\heqno|
% nor |\nydeleqno| gives any equation numbers at all in the
% |deqrarr| environment.
%
% \item{|\nydeqno|} \DescribeMacro{\nydeqno} \\
% Used within |deqarr| and |ddeqar| environments to
% step the main equation number by one and reset the
% partial equation number to `a'; thus, |\nydeqno| gives
% equation number `4a' when following after equation `3c'.
%
% \item{|\heqno|} \DescribeMacro{\heqno} \\
% Used within |deqarr| and |ddeqar|
% environments to step the main equation number by one and
% to produce an ordinary equation number; thus, gives
% equation number `4' when following equation `3c'.
% Equations following the |\heqno|-ed will be partially
% numbered with the |\heqno|-ed equation's number as the
% main number, \textit{e.g.}\ `4a' (unless it has a |\nydeqno|
% command, which in this case would produce the equation
% number `5a').
%
% \item{|\reqno{FOO}|} \DescribeMacro{\reqno} \\
% Is used when repeating an equation with its original
% number, ``recycling'' the eqaution number.
% |\reqno| takes the argument |FOO|, which has to be defined
% by a |\label{FOO}| in the original equation. It can
% only be used within |$$ ... $$|. It does not affect the
% equation number counter, nor the ordinary partial equation number
% counter. However, it resets the partial equation number
% counter for the |\rndeqno|, |\rdeqno|, |\deqreqno|, and
% |\ddeqreqno| commands. If used with a |\label{FOOO}|
% command, the |.aux|-file will only contain the page number
% of label |FOOO|. This command is not compatible with the
% class option |fleqn|. Instead of |$$ ... \reqno{FOO} $$|,
% use a one-line |deqrarr| environment with the commands
% |\eqreqno[-\jotbaseline]{FOO} \nonumber| at the end.
%
% \item{|\rndeqno{FOO}|} \DescribeMacro{\rndeqno} \\
% Adds a partial equation number to an old equation number,
% specified by the |FOO| label. If |FOO| refers to equation
% `4', |\rdeqno{FOO}| will result in equation number `4a'
% (always `a'). It can only be used within
% |$$ ... $$|. It does not affect the equation number counter,
% nor the ordinary partial equation number counter. However, it
% resets the partial equation number counter for the
% |\rndeqno|, |\rdeqno|, |\deqreqno|, and |\ddeqreqno| commands.
% The argument of |\rndeqno| follows the same rules as that of
% |\reqno|. When used with the |\label{FOOO}| command, a
% reference to |FOOO| will only return the partial equation
% number (and the page number). To make a complete reference
% to an equation which has a |\rndeqno| command, say
% |\ref{FOO}\ref{FOOO}|. This command is not compatible with the
% class option |fleqn|. Instead of |$$ ... \rndeqno{FOO} $$|,
% use a one-line |deqrarr| environment with the commands
% |\deqreqno[-\jotbaseline]{FOO} \nonumber| at the end.
%
% \item{|\rdeqno{FOO}|} \DescribeMacro{\rdeqno} \\
% Same as |\rndeqno{FOO}| but without resetting any
% equation number counter and giving consecutive partial
% equation numbers (`4b', `4c', \textit{etc.}).
% \textbf{Note: } There is nothing preventing the
% repeated use of |\rndeqno{FOO}| and |\rdeqno{FOO}| for
% the same label |FOO|. This will result in numbering such
% as `3a' (if |FOO| refers to equation `3') occuring several
% times. This command is not compatible with the
% class option |fleqn|. Instead of |$$ ... \rdeqno{FOO} $$|,
% use a one-line |deqrarr| environment with the commands
% |\ddeqreqno[-\jotbaseline]{FOO} \nonumber| at the end.
%
% \item{|\eqreqno[|\textit{len}|]{FOO}|}
% \DescribeMacro{\eqreqno} \\
% This command is the array-like version of |\reqno{FOO}| and
% is used in much the same way. The optional argument \textit{len}
% is a length which is added between consecutive rows in the array-like
% structure. When using |\eqreqno| no `|\\|' should be issued
% at the end of the line, it is embedded in the command. This
% is giving a strange appearance if |\eqreqno| is used on the
% last line of the array-like sturcture, namely an extra blank
% line (with equation number). To avoid this problem, specify
% a negative length for \textit{len}, preferably `|-\jotbaseline|'
% (se below), and issue a `|\nonumber|' afterwards.
%
% \item{|\deqreqno[|\textit{len}|]{FOO}|}
% \DescribeMacro{\deqreqno} \\
% This is the `|\rndeqno|' version of `|\eqreqno|' and is used
% as the former with the latter's abilities at the end of a
% line.
%
% \item{|\ddeqreqno[|\textit{len}|]{FOO}|}
% \DescribeMacro{\ddeqreqno} \\
% This is the `|\rdeqno|' version of `|\eqreqno|' and is used
% as the former with the latter's abilities at the end of a
% line.
%
% \item{|\arrlabel{FOO}|} \DescribeMacro{\arrlabel} \\
% This command is a version of \LaTeX 's ordinary
% |\label{FOO}| command meant to be used in |deqarr| and
% |ddeqar| environments. In these environments, a
% |\label{FOO}| command gives a reference to the specific
% equation, \textit{e.g.}\ 3b, whereas |\arrlabel{FOO}| in the
% same position gives a reference containing only the main
% equation number, 3 in this example. For restrictions, see
% the section ``Notice'' above. The four commands |\eqreqno|,
% |\deqreqno|, |\ddeqreqno|, and |\arrlabel| were created after
% inspiration from Larry Jones (\texttt{schnuff@mit.edu}).
%
% \item{|\where|} \DescribeMacro{\where} \\
% The command |\where| typsets the text ``where'' (in
% the default LR-font) flush left on a seperate row in
% |eqnarray|, |deqarr|, |ddeqar|, and |deqrarr| environments,
% and preserves the environment's alignment for rows to come.
%
% \item{|\rem{|\textit{text}|}|} \DescribeMacro{\rem{text}} \\
% The command |\rem{|\textit{text}|}| typsets the text
% ``\textit{text}'' (in the default LR-font) flush left on
% a seperate row in |eqnarray|, |deqarr|, |ddeqar|, and |deqrarr|
% environments, and preserves the environment's alignment
% for rows to come. |\where| is equivalent to
% |\rem{where}|.
%
% \item{|\nydeleqno|} \DescribeMacro{\nydeleqno} \\
% Gives a new partial equation number when used within |$$ ... $$|.
% Thus, writing |$$ ...| |\nydeleqno $$| is equivalent to
% writing |\begin{deqn} ... \end{deqn}|.
% This command is not compatible with the
% class option |fleqn|, use |\begin{deqn} ... \end{deqn}|
% instead.
%
% \item{|\deleqno|} \DescribeMacro{\deleqno} \\
% Gives a partial equation number when used within |$$ ... $$|.
% Thus, writing |$$ ...| |\deleqno| |$$| is equivalent to
% writing |\begin{ddeqn} ... \end{ddeqn}|.
% This command is not compatible with the
% class option |fleqn|, use |\begin{ddeqn} ... \end{ddeqn}|
% instead.
%
% \item{|\jotbaseline|} \DescribeMacro{\jotbaseline} \\
% This is a rubber length which is set to be the sum of
% |\baselinsekip| and |\jot| each time a |deqarr|, |ddeqar|,
% or a |deqrarr| environment is enterd. It is meant to be
% used with the |\eqreqno| command and its relatives to
% eliminate the problems when these commands are used on the
% last line of the environment. (The length |\baselineskip| +
% |\jot| is the length \LaTeX{} skips between two
% empty lines in an `|eqnarray|' environment and its
% derivates defined in \textsf{deleq}.)
%
% \end{description}
%
% \section{Example}
% After running \LaTeX{} on |deleq.ins|, there is an
% example avaliable in the file |delex.tex|,
% which makes use of all the environments and commands
% defined in the \textsf{deleq} package. Typset it and see with
% your own eyes what the results are!
%
%
% \section{Sending a Bug Report}
% \textsf{deleq} is most likely to contain bugs.
% Reports of bugs in the package are most welcome.
% Before filing a bug report,
% please take the following actions:
% \begin{enumerate}
% \item Ensure your problem is not due to your inputfile;
% \item Ensure your problem is not due to
% your own package(s) or class(es);
% \item Ensure your problem is not covered in the section
% ''Known Problems'' above;
% \item Try to locate the problem by writing a minimal
% \LaTeX{} input file which reproduces the problem.
% Include the command\\
% | \setcounter{errorcontextlines}{999}|\\
% in your input;
% \item Run your file through \LaTeX{};
% \item Send a description of your problem, the input file
% and the log file via e-mail to:\\
% | matsd@sssk.se|
% \end{enumerate}
% {\itshape Enjoy your \LaTeX!\raisebox{-\baselineskip}{mats d.}}
% \StopEventually{\par\vfill\hfill{\scriptsize Copyright
% \copyright{} 1994-98 by Mats Dahlgren.}}
% \newpage
%
% \section{The Code}
% For the interested reader(s), here is a short description
% of the code. \par
% \iffalse
%<*paketkod>
% Part 1: Identification etc.
% \fi
% First, the package is to identify itself.
% \begin{macrocode}
\NeedsTeXFormat{LaTeX2e}[1996/12/01]
\ProvidesPackage{deleq}[1997/07/07 v.4.41 Partial equation numbering]
\def\deleqver{\textsf{deleq} version 4.41 (July~7, 1997)}
% \end{macrocode}
% \iffalse
% Part 2: Counters and internal commands, etc.
% \fi
% \par Then, we need to define the counters used for the partial
% part of the equation number. The counter |Deleq| is used for
% ``recycled'' equation numbers, hence no dependence on any other
% counter.
% \begin{macrocode}
\newcounter{deleq}[equation]
\newcounter{Deleq}
\newlength{\jotbaseline}
\renewcommand{\thedeleq}{\ensuremath{\theequation\mathrm{\alph{deleq}}}}
\renewcommand{\theDeleq}{\ensuremath{\mathrm{\alph{Deleq}}}}
\def\@deleqnnum{(\thedeleq)}
\def\@deleqrnum#1{(\ref{#1}\theDeleq)}
\def\@eqrnum#1{(\ref{#1})}
% \end{macrocode}
% The parts making up the |\\| command in the multiline environments
% are similar to those used by the standard environments
% (at least how they looked some time ago):
% \begin{macrocode}
\def\@deqncr{{\ifnum0=`}\fi\@ifstar{\global\@eqpen\@M
\@ydeqncr}{\global\@eqpen\interdisplaylinepenalty \@ydeqncr}}
\def\@ydeqncr{\@ifnextchar [{\@xdeqncr}{\@xdeqncr[\z@]}}
\def\@xdeqncr[#1]{\ifnum0=`{\fi}\@@deqncr
\noalign{\penalty\@eqpen\vskip\jot\vskip #1\relax}}
\def\@@deqncr{\let\@tempa\relax
\ifcase\@eqcnt \def\@tempa{& & &}\or \def\@tempa{& &}%
\else \def\@tempa{&}\fi
\@tempa \if@eqnsw\@deleqnnum\stepcounter{deleq}\fi
\global\@eqnswtrue\global\@eqcnt\z@\cr}
\newcommand{\@xeqrcr}[2]{\ifnum0=`{\fi}\@@eqrcr{#2}
\noalign{\penalty\@eqpen\vskip\jot\vskip #1\relax}}
\def\@@eqrcr#1{\let\@tempa\relax
\ifcase\@eqcnt \def\@tempa{& & &}\or \def\@tempa{& &}%
\else \def\@tempa{&}\fi
\@tempa \if@eqnsw\@eqrnum{#1}\fi
\global\@eqnswtrue\global\@eqcnt\z@\cr}
\newcommand{\@xdeqrcr}[2]{\ifnum0=`{\fi}\@@deqrcr{#2}
\noalign{\penalty\@eqpen\vskip\jot\vskip #1\relax}}
\def\@@deqrcr#1{\let\@tempa\relax
\ifcase\@eqcnt \def\@tempa{& & &}\or \def\@tempa{& &}%
\else \def\@tempa{&}\fi
\@tempa \if@eqnsw\@deleqrnum{#1}\fi
\global\@eqnswtrue\global\@eqcnt\z@\cr}
\def\@deqrarcr{{\ifnum0=`}\fi\@ifstar{\global\@eqpen\@M
\@ydeqrarcr}{\global\@eqpen\interdisplaylinepenalty \@ydeqrarcr}}
\def\@ydeqrarcr{\@ifnextchar [{\@xdeqrarcr}{\@xdeqrarcr[\z@]}}
\def\@xdeqrarcr[#1]{\ifnum0=`{\fi}\@@deqrarcr
\noalign{\penalty\@eqpen\vskip\jot\vskip #1\relax}}
\def\@@deqrarcr{\let\@tempa\relax
\ifcase\@eqcnt \def\@tempa{& & &}\or \def\@tempa{& &}%
\else \def\@tempa{&}\fi
\@tempa \global\@eqnswtrue\global\@eqcnt\z@\cr}
% \end{macrocode}
% \iffalse
% Part 3: Commands: \nydeleqno, \deleqno, \reqno, \rndeqno, \rdeqno,
% \eqreqno, \deqreqno, \ddeqreqno, \arrlabel,
% \nydeqno, and \heqno
% \fi
% \par Here the definitions of the user commands are.
% \begin{macrocode}
\newcommand{\nydeleqno}{\stepcounter{equation}\stepcounter{deleq}
\let\@currentlabel\thedeleq \eqno (\thedeleq)}
\newcommand{\deleqno}{\refstepcounter{deleq} \let\@currentlabel\thedeleq
\eqno (\thedeleq)}
\newcommand{\reqno}[1]{\setcounter{Deleq}{-1}\refstepcounter{Deleq}
\eqno (\ref{#1})}
\newcommand{\rdeqno}[1]{\refstepcounter{Deleq}
\eqno (\ref{#1}\theDeleq)}
\newcommand{\rndeqno}[1]{\setcounter{Deleq}{0}\refstepcounter{Deleq}
\eqno (\ref{#1}\theDeleq)}
\newcommand{\eqreqno}[2][0pt]{{\ifnum0=`}\fi\@ifstar{\global\@eqpen\@M
\@xeqrcr{#1}{#2}}{\global\@eqpen\interdisplaylinepenalty
\@xeqrcr{#1}{#2}}}
\newcommand{\deqreqno}[2][0pt]{\setcounter{Deleq}{0}\refstepcounter{Deleq}
{\ifnum0=`}\fi\@ifstar{\global\@eqpen\@M
\@xdeqrcr{#1}{#2}}{\global\@eqpen\interdisplaylinepenalty
\@xdeqrcr{#1}{#2}}}
\newcommand{\ddeqreqno}[2][0pt]{\refstepcounter{Deleq}
{\ifnum0=`}\fi\@ifstar{\global\@eqpen\@M
\@xdeqrcr{#1}{#2}}{\global\@eqpen\interdisplaylinepenalty
\@xdeqrcr{#1}{#2}}}
\newcommand{\arrlabel}[1]{\let\@currentlabel\theequation \label{#1}}
\newcommand{\nydeqno}{\stepcounter{equation}\stepcounter{deleq}}
\newcommand{\heqno}{\stepcounter{equation}}
\def\where{\let\@tempa\relax \def\@tempa{& & &}
\@tempa {\hbox to .01\p@{}\rlap{\hskip -\displaywidth where}}\cr}
\def\rem#1{\let\@tempa\relax \def\@tempa{& & &}
\@tempa {\hbox to .01\p@{}\rlap{\hskip -\displaywidth #1}}\cr}
% \end{macrocode}
% \iffalse
% Part 4: Environments: 'deqarr', 'ddeqar', 'deqn', 'ddeqn', and 'deqrarr'
% \fi
% \par The five environments are slight modifications of the
% corresponding \LaTeX{} standard environments. The main difference
% lies in which counter(s) is stepped and which internals are used to
% finish off the lines. Three of them have large parts in
% common, parts which are put in one macro `|\@dlqnv|':
% \begin{macrocode}
\def\@dlqnv{\setlength{\jotbaseline}{\baselineskip}%
\addtolength{\jotbaseline}{\jot} \global\@eqnswtrue\m@th
\global\@eqcnt\z@\tabskip\@centering
$$\halign to\displaywidth\bgroup\@eqnsel\hskip\@centering
$\displaystyle\tabskip\z@{##}$&\global\@eqcnt\@ne
\hskip 2\arraycolsep \hfil${##}$\hfil
&\global\@eqcnt\tw@ \hskip 2\arraycolsep $\displaystyle\tabskip\z@{##}$\hfil
\tabskip\@centering&\llap{##}\tabskip\z@\cr}
\newenvironment{deqarr}{\stepcounter{equation}\stepcounter{deleq}
\let\@currentlabel\thedeleq \let\\\@deqncr \@dlqnv}
{\@@deqncr\egroup
\global\advance\c@deleq\m@ne$$\global\@ignoretrue}
\newenvironment{ddeqar}{\stepcounter{deleq}
\let\@currentlabel\thedeleq \let\\\@deqncr \@dlqnv}
{\enddeqarr}
\newenvironment{deqn}{$$\refstepcounter{equation}\stepcounter{deleq}
\let\@currentlabel\thedeleq}
{\eqno \hbox{\@deleqnnum} $$\global\@ignoretrue}
\newenvironment{ddeqn}{$$\refstepcounter{deleq} \let\@currentlabel\thedeleq}
{\enddeqn}
\newenvironment{deqrarr}{\let\@currentlabel\theDeleq
\let\\\@deqrarcr \@dlqnv}
{\@deqrarcr \egroup $$\global\@ignoretrue}
% \end{macrocode}
% \iffalse
% Part 5: 'leqno' compatibility
% \fi
% \par If the user wants the equation numbers to the left, we have to
% modify some of the commands and internals defined above. This is
% done in a |\DeclareOption|-call, but first we set a
% switch to test for the |leqno| option. Initially, it is set
% to |F| and then changed to |T| if the |leqno| option is in effect.
% \begin{macrocode}
\newif\ifl@qn \l@qnfalse
\DeclareOption{leqno}{%
\global\l@qntrue%
\renewcommand{\@deleqnnum}{\hbox to .01\p@{}\rlap{\reset@font\rmfamily
\hskip -\displaywidth(\thedeleq)}}
\renewcommand{\nydeleqno}{\stepcounter{equation}\stepcounter{deleq}
\let\@currentlabel\thedeleq \leqno (\thedeleq)}
\renewcommand{\deleqno}{\refstepcounter{deleq} \let\@currentlabel\thedeleq
\leqno (\thedeleq)}
\renewcommand{\reqno}[1]{\setcounter{Deleq}{-1}\refstepcounter{Deleq}
\leqno (\ref{#1})}
\renewcommand{\rdeqno}[1]{\refstepcounter{Deleq}
\leqno (\ref{#1}\theDeleq)}
\renewcommand{\rndeqno}[1]{\setcounter{Deleq}{0}\refstepcounter{Deleq}
\leqno (\ref{#1}\theDeleq)}
\renewcommand{\@eqrnum}[1]{\hbox to .01\p@{}\rlap{\reset@font\rmfamily
\hskip -\displaywidth(\ref{#1})}}
\renewcommand{\@deleqrnum}[1]{\hbox to .01\p@{}\rlap{\reset@font\rmfamily
\hskip -\displaywidth(\ref{#1}\theDeleq)}}
}
% \end{macrocode}
% \iffalse
% Part 6: `fleqn' compatibility
% \fi
% \par The |fleqn| option is mainly a `\textsf{deleq}-ification' of
% the \LaTeXe{} file |fleqn.clo| (1995/06/26 v1.3g). If both
% |leqno| and |fleqn| options are in use, the length
% |\mathindent| should be increased to allow space for the
% letters of the partial equation numbers. For the
% multiline environments, it is enough to make changes to the
% internal |\@dlqnv|.
% \begin{macrocode}
\DeclareOption{fleqn}{%
\ifl@qn \AtBeginDocument{\addtolength{\mathindent}{1em}} \fi
\renewenvironment{deqn}%
{\@beginparpenalty\predisplaypenalty
\@endparpenalty\postdisplaypenalty
\refstepcounter{equation}\stepcounter{deleq}
\let\@currentlabel\thedeleq%
\trivlist \item[]\leavevmode
\hb@xt@\linewidth\bgroup $\m@th% $
\displaystyle
\hskip\mathindent}%
{$\hfil % $
\displaywidth\linewidth\hbox{\@deleqnnum}%
\egroup
\endtrivlist}
\renewenvironment{ddeqn}%
{\@beginparpenalty\predisplaypenalty
\@endparpenalty\postdisplaypenalty
\refstepcounter{deleq}
\let\@currentlabel\thedeleq%
\trivlist \item[]\leavevmode
\hb@xt@\linewidth\bgroup $\m@th% $
\displaystyle
\hskip\mathindent}%
{\enddeqn}
\renewcommand{\@dlqnv}{%
\setlength{\jotbaseline}{\baselineskip}
\addtolength{\jotbaseline}{\jot}
\global\@eqcnt\z@
\tabskip\mathindent
\setlength\abovedisplayskip{\topsep}%
\ifvmode
\addtolength\abovedisplayskip{\partopsep}%
\fi
\addtolength\abovedisplayskip{\parskip}%
\setlength\belowdisplayskip{\abovedisplayskip}%
\setlength\belowdisplayshortskip{\abovedisplayskip}%
\setlength\abovedisplayshortskip{\abovedisplayskip}%
$$\everycr{}\halign to\linewidth% $$
\bgroup
\hskip\@centering
$\displaystyle\tabskip\z@skip{##}$\@eqnsel&%
\global\@eqcnt\@ne \hskip \tw@\arraycolsep \hfil${##}$\hfil&%
\global\@eqcnt\tw@ \hskip \tw@\arraycolsep
$\displaystyle{##}$\hfil \tabskip\@centering&%
\global\@eqcnt\thr@@
\hb@xt@\z@\bgroup\hss##\egroup\tabskip\z@skip\cr}
}
% \end{macrocode}
% If other options were asked for, the package should make
% these options `unused'. Then, last, the option(s)
% is (are) processed.
% \begin{macrocode}
\DeclareOption*{\OptionNotUsed}
\ProcessOptions
% \end{macrocode}
% That is all. Happy \TeX-ing!
% \iffalse
% END of it all!
%</paketkod>
%<*exempelkod>
\documentclass[11pt]{article} %%% add `leqno' if you want left-aligned
\usepackage{deleq} %%% equation numbers and `fleqn' to
\oddsidemargin=0.5cm %%% flush the equations left.
\evensidemargin=0.5cm
\topmargin=-5mm
\textheight=23.5cm
\textwidth=15.5cm
\begin{document}
\begin{center}
\Large Welcome to the \textsf{deleq} package!
\end{center}
This is a short document to demonstrate the use of the
\textsf{deleq} package and its commands. It uses \deleqver .
\textsf{deleq} was written by Mats Dahlgren
(\texttt{matsd@sssk.se http://www.homenet.se/matsd/}). Suggestions for
improvements and bug reports are most welcome, see the
documentation. \textsf{deleq} is fully compatible with the
\texttt{leqno} option and most of the \texttt{fleqn} option.
We start this demonstration by a simple and well-known
equation to get the equation number counter going:
\begin{equation}
\sin^2\alpha + \cos^2\alpha = 1
\end{equation}
The first example will be to make use of the
\texttt{deqn} environment to get a partially numbered
equation:
\begin{deqn}
\sin (-\alpha) = - \sin \alpha
\end{deqn}
This equation has its cosine companion, here written in
the \texttt{ddeqn} environment:
\begin{ddeqn}
\cos (-\alpha) = \cos \alpha
\end{ddeqn}
Not so exciting, so far. :--)
In the next example we introduce the \texttt{deqarr}
environment for writing equations:
\begin{deqarr}
\sin ( \alpha + \beta ) & =
& \sin \alpha \cos \beta + \sin \beta \cos \alpha \\
\sin ( \alpha - \beta ) & =
& \sin \alpha \cos \beta - \sin \beta \cos \alpha
\label{Demo1}
\end{deqarr}
where we also have put in the label \texttt{Demo1} in
the second equation. Next, notice how the environment
\texttt{ddeqar} uses the same main equation number as
the previous equations:
\begin{ddeqar}
\cos ( \alpha + \beta ) & =
& \cos \alpha \cos \beta - \sin \alpha \sin \beta
\arrlabel{Demo2} \\
\cos ( \alpha - \beta ) & =
& \cos \alpha \cos \beta + \sin \alpha \sin \beta
\end{ddeqar}
In the first of these equations, an \verb+\arrlabel+ command
with the label \texttt{Demo2} is included.
Now, we will make another \texttt{eqnarray}-like
structure, again in the \texttt{ddeqar} environment:
\begin{ddeqar}
\sin 2\alpha & =
& 2 \sin \alpha \cos \alpha \heqno \label{Demo3} \\
\cos 2\alpha & =
& \cos ^2 \alpha - \sin ^2 \alpha \nydeqno \\
\rem{or}
& = & 2\cos ^2 \alpha - 1
\end{ddeqar}
This example shows the use of \verb$\heqno$ in the first
equation, which produces an ordinary equation number.
The first equation is also labelled, with the label
\texttt{Demo3}. The next equation's number was produced
by the command \verb$\nydeqno$. Also, notice the use of
\verb+\rem{or}+, which results in the text ``or'' without
changing the alignment. To illustrate the use of
\verb+\arrlabel{Demo2}+ above, we here make a reference to it:
\ldots{} in equations \ref{Demo2} \ldots which was
created by typing
`\verb+\ldots{} in equations \ref{Demo2} \ldots+'.
To step the equation number counter, we want the
following equations typeset in ordinary
\texttt{eqnarray} environment:
\begin{eqnarray}
\tan ^2 \alpha & =
& \frac{\sin ^2 \alpha}{\cos ^2 \alpha} \label{Demo4} \\
\tan \alpha & =
& \frac{\sin \alpha}{\cos \alpha}
\end{eqnarray}
The upper equation was given the label \texttt{Demo4}.
Now one of the ``recycling'' commands is to be
demonstrated. First of all, let's make an ordinary
reference to equation~\ref{Demo3}, and then ``recycle'' it:
$$ \sin 2\alpha = 2 \sin \alpha \cos \alpha \reqno{Demo3} $$
This was obtained with \verb#$$ ... $$# with the command
\verb#\reqno{Demo3}# at the end. Also partially
numbered equations can be recycled with the
\verb#\reqno{FOO}# command, as with
equation~\ref{Demo1}:
$$ \sin ( \alpha - \beta ) = \sin \alpha \cos \beta -
\sin \beta \cos \alpha \reqno{Demo1} $$
(However, the use of \verb#\rndeqno{FOO}# and
\verb#\rdeqno{FOO}# will produce strange results with
two (different) partial equation numbers if \texttt{FOO}
refers to a partially numbered equation.)
The next equation was written with \verb#$$ ... $$# and
a \verb#\deleqno# command at the end:
$$ \tan 2\alpha = \frac{2\tan \alpha}{1 - \tan ^2 \alpha} \deleqno $$
Notice how the main equation number counter is still the
same, despite that we now are outside of the
\texttt{ddeqar} environment. Also, notice how the use of
\verb#\reqno# above did not affect the equation number
counter. The following equation is also set within
\verb#$$ ... $$#, but it uses the command
\verb#\nydeleqno# to produce an equation number with a
new main number:
$$ \sin ^2 \alpha = 1 - \cos ^2 \alpha \nydeleqno $$
Now we will elaborate a little on \verb#\rndeqno{FOO}#
and \verb#\rdeqno{FOO}#. Let us use
equation~\ref{Demo4}, and see what happens if we use the
\verb#\rndeqno{FOO}# command:
$$ \tan ^2 \alpha = \frac{\sin ^2 \alpha}
{\cos ^2 \alpha} \rndeqno{Demo4} $$
which we rewrite:
$$ \tan ^2 \alpha = \frac{\sin ^2 \alpha}
{1 - \sin ^2 \alpha} \rdeqno{Demo4} \label{Demo5} $$
with \verb#\rdeqno{Demo4}# at the end. This is great
fun, so why not one more:
\begin{deqrarr}
\tan ^2 \alpha = \frac{1 - \cos ^2 \alpha}
{\cos ^2 \alpha} \ddeqreqno[-\jotbaseline]{Demo4}
\nonumber
\end{deqrarr}
Also, the middle form of equation~\ref{Demo4} got a
label, \texttt{Demo5}. In the last example, the construct\\
\verb+ \ddeqreqno[-\jotbaseline]{Demo4} \nonumber+\\ in a
\texttt{deqrarr} environment is used, to obtain
\texttt{fleqn} compatibility.
There is still one equation to write. This time we
again use the \texttt{deqarr} environment:
\begin{deqarr}
\cot \alpha & = & \frac{\cos \alpha}{\sin \alpha} \\
\where
& = & \frac{1}{\tan \alpha}
\end{deqarr}
This example also shows the use of the \verb+\where+
command, which is a special case of the \verb+\rem+ command.
Now, the interesting thing of referring to the recycled
equations is ahead. If one writes \verb#\ref{Demo5}#,
this is what \LaTeX\ will return:~\ref{Demo5}. That is
not too instructive, since the partial equation numbers
are quite common in this document. To make the complete
reference, use \verb#\ref{Demo4}\ref{Demo5}#. The
reference~\ref{Demo4}\ref{Demo5} is much more
comprehensible, right? (If you get bad line-breaks at
such references, put them in an \verb#\mbox{...}#.)
Now we will show the use of the commands to recycle equation
numbers in \verb+eqnarray+-like structures. These commands
are \verb+\eqreqno{FOO}+, \verb+\deqreqno{FOO}+, and
\verb+\ddeqreqno{FOO}+. We start by repeating equation
\ref{Demo1} in an \verb+deqrarr+ environment:
\begin{deqrarr}
\sin ( \alpha - \beta ) & =
& \sin \alpha \cos \beta - \sin \beta \cos \alpha
\eqreqno{Demo1}
\sin 2\alpha & = & 2 \sin\alpha \cos\alpha
\end{deqrarr}
The second equation here shows how the alignment of the
equations is preserved. Next, we can use the equation
\ref{Demo3} for some variations:
\begin{deqrarr}
\sin 2\alpha & = & 2 \sin\alpha \cos\alpha
\deqreqno{Demo3}
\sin 4\alpha & = & 2 \sin 2\alpha \cos 2\alpha \\
& = & 2\left( 2\sin\alpha \cos\alpha
\left( \cos^2 \alpha - \sin^2 \alpha\right)\right)
\ddeqreqno{Demo3}
& = & 4\left(\sin\alpha \cos\alpha
\left( \cos^2 \alpha - \sin^2 \alpha\right)\right)
\ddeqreqno[-\jotbaseline]{Demo3}
\end{deqrarr}
The features used here are \verb+\deqreqno{Demo3}+
on the first line, \verb+\ddeqreqno{Demo3}+ on the
second line, and \verb+\deqreqno[-\jotbaseline]{Demo3}+
on the third. Note how the inclusion of
\verb+[-\jotbaseline]+ on the third line prevents
\LaTeX{} from inserting an extra blank line. The
second line ends with `\verb+\\+', and has thus no
equation number at all.
The last part shows how you may use \verb+\eqreqno+ and its
relatives in \verb+deqarr+ environment:
\begin{deqarr}
\sin\alpha & = & \sin\alpha \cos 0 + \sin 0 \cos\alpha \\
\sin 2\alpha & = & 2 \sin\alpha \cos\alpha \eqreqno{Demo3}
\sin 3\alpha & = & \sin 2\alpha \cos\alpha +
\sin\alpha \cos 2\alpha \\
\sin 4\alpha & = & 2 \sin 2\alpha \cos 2\alpha \\
\sin 5\alpha & = & \sin 3\alpha \cos 2\alpha +
\sin 2\alpha \cos 3\alpha \ddeqreqno{Demo3}
\sin 6\alpha & = & 2 \sin 3\alpha \cos 3\alpha
\end{deqarr}
The interesting part here is an `\verb+\eqreqno{Demo3}+' at
the end of the second line and a `\verb+\ddeqreqno{Demo3}+' at
the end of the fifth line. Notice how the partial
equation number counter in unaffected by the enetering of
the \verb+deqarr+ environment.
Finally, the $\mathcal{END}$! If you want your
equation numbers left-aligned, just specify the \texttt{leqno}
option for the \texttt{documentclass} you are using. It
should work! If you have any suggestions, corrections
or contributions, please contact me. Enjoy \LaTeX !
{\itshape mats d.}
\end{document}
%</exempelkod>
% \fi
%
% \Finale
%
\endinput