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- % \iffalse
- % The first part is a comment to the reader(s) of `deleq.dtx'.
- % deleq.dtx Version 4.1, Dec. 27, 1994
- % (c) 1994 by Mats Dahlgren (matsd@physchem.kth.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.
- % This file may NOT be distributed if not accompanied by 'deleq.ins'.
- % \fi
- % \def\filename{deleq.dtx}
- % \def\fileversion{4.1}
- % \def\filedate{1994/12/27}\def\docdate{\filedate}
- % \MakeShortVerb{\|}
- % \title{\LaTeX{} Macro for Partial Numbering of Equations}
- % \author{Mats Dahlgren\\ (\texttt{matsd@physchem.kth.se})}
- % \maketitle
- % \begin{abstract}
- % To enable a more flexible equation numbering, especially
- % ``partial'' equation numbers (`3a', `3b' \textit{etc.}),
- % the |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. The
- % package also provides commands for putting commentatory
- % text in an |eqnarray| environment without requiering the
- % |amstex| package.\\ \small This file and the package:\
- % Copyright \copyright\ 1994 by Mats Dahlgren. All rights
- % reserved.
- % \end{abstract}
- % \section{Introduction}
- % |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. |deleq| is fully
- % compatible with the |leqno| documentclass 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). 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
- % commnetary tests in |eqnarray|-like environments without
- % interfering with the alignment.
- % \section{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 previous release (v.4.0, Oct.~14,
- % 1994) was the first for \LaTeXe. The present release
- % (v.4.1) is the first which is compatible with the
- % |docstrip| utility of Johannes Braams, Denys Duchier and
- % Frank Mittelbach.
- % |deleq.sty| version 4.0 has been tested with \LaTeXe%
- % /\TeX{} 3.141 under UNIX and \LaTeXe /\TeX{} 3.1415 under
- % OpenVMS. Version 4.1 has only been tested on the
- % OpenVMS platform. Please send bug reports (see below),
- % corrections, additions, suggestions, \textit{etc.}\ to
- % me at \texttt{matsd@physchem.kth.se}. (Command names
- % are a mixture of \LaTeX , Swedish and a bit of the
- % author's fantasy$\ldots$) With |deleq| v.4.1, the
- % commentatory commands |\where| and |\rem| were included.
- % \section{Known Problems}
- % \begin{itemize}
- % \item Earlier versions (3.0) of |deleq.sty| had
- % problems with \LaTeXe compatibility mode (reported by
- % Tom Scavo (\texttt{trscavo@mailbox.syr.edu})). These
- % problems are likely to remain. There are also problems
- % with the font selections when using older versions of
- % |deleq| than 4.0 in \LaTeXe{} native mode. These error
- % messages can be ignored, \LaTeXe{} will produce the
- % correct output anyway. There will not be any attempts
- % to correct this by the author of |deleq| in the near
- % future.
- % \item In \LaTeX{} 2.09, the use of |deleq.sty| version
- % 3.0 sometimes caused the |\em| command not to work
- % properly in a theorem-like environment (reported by
- % Patrick Dan\`es (\texttt{danes@laas.fr})). This appears
- % not to be a problem in \LaTeXe{} with |deleq| version
- % 4.0 and later.
- % \end{itemize}
- % \section{``Userguide''}
- % \subsection{Requirements}
- % The file |deleq.sty| must be available in the user's
- % |TEXINPUTS| directories.
- % It requires \LaTeXe{} of 1994/06/01 (or newer).
- % \subsection{Usage}
- % The package is included by stating\\
- % | \usepackage{|$\ldots$|,deleq,|$\ldots$|}| \\
- % In the document preamble.
- % The documentclass option |leqno| is fully supported,
- % no other class or package options have any effect on
- % |deleq|.
- % \subsection{Environments}
- % The package defines the following four environments:
- % \begin{description}
- % \item{\texttt{deqn}} environment for automatic numbering of
- % the first equation of type 3a;
- % \item{\texttt{ddeqn}} used for automatic numbering of the
- % equations following the one in |deqn|, see also details
- % below;
- % \item{\texttt{deqarr}} environment for automatic partial equation
- % numbering used in |eqnarray| environment with
- % |deqn| functionality for the first equation;
- % \item{\texttt{ddeqar}} similar to |deqarr| environment, but
- % with |ddeqn| behaviour for the first equation, see details below.
- % \end{description}
- % \subsection{Commands}
- % The package defines the following nine user commands:\\
- % \hspace*{2mm}|\nydeqno|\\
- % \hspace*{2mm}|\heqno|\\
- % \hspace*{2mm}|\nydeleqno|\\
- % \hspace*{2mm}|\deleqno|\\
- % \hspace*{2mm}|\reqno{FOO}|\\
- % \hspace*{2mm}|\rndeqno{FOO}|\\
- % \hspace*{2mm}|\rdeqno{FOO}|\\
- % \hspace*{2mm}|\where|\\
- % \hspace*{2mm}|\rem{|\textit{text}|}|\\
- % \subsection{Notice}
- % \begin{enumerate}
- % \item If you use |\nydeleqno|, |\deleqno|, |\nydeqno|,
- % |\heqno|, |\reqno|, |\rndeqno|, or |\rdeqno| in
- % combination with |\label{FOO}|, |\label{FOO}| should
- % appear after the |deleq|-command;
- % \item If you change the appearance of equation numbers
- % (\textit{e.g.}\ use
- % `[2]' instead of `(2)'), |deleq|'s commands may not typeset
- % the partial equation numbers like your ordinary ones.
- % \end{enumerate}
- % \section{Syntax}
- % Here follows a more detailed description of the
- % different environments and commands. \\[1em]
- % \noindent|\begin{deqn} ... \end{deqn}|\\
- % Typesets an equation just like
- % |\begin{equation} ... \end{equation}| does, but gives it
- % a number such as `3a' instead of `3' (always `a'). \\[1em]
- % \noindent|\begin{ddeqn} ... \end{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). \\[1em]
- % \noindent|\begin{deqarr} ... \end{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.} The |\nonumber| command works just like
- % in the |eqnarray| environment. \\[1em]
- % \noindent|\begin{ddeqar} ... \end{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|.
- % The |\nonumber| command works just like in the
- % |eqnarray| environment. \\[1em]
- % \noindent|\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'.\\[1em]
- % \noindent|\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').\\[1em]
- % \noindent|\nydeleqno|\\
- % Gives a new partial equation number when used within |$$ ... $$|.
- % Thus, writing |$$ ...| |\nydeleqno $$| is equivalent to
- % writing |\begin{deqn} ... \end{deqn}|.\\[1em]
- % \noindent|\deleqno|\\
- % Gives a partial equation number when used within |$$ ... $$|.
- % Thus, writing |$$ ... \deleqno $$| is equivalent to
- % writing |\begin{ddeqn} ... \end{ddeqn}|. \\[1em]
- % \noindent|\reqno{FOO}|\\
- % Is used when repeating equations with its original 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 partial equation number
- % counter. However, it resets the partial equation number
- % counter for the |\rndeqno| and |\rdeqno|
- % commands. If used with a |\label{FOOO}|
- % command, the |.aux|-file will only contain the page number
- % of label |FOOO|. \\[1em]
- % \noindent|\rndeqno{FOO}|\\
- % 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 partial equation number counter. However, it
- % resets the partial equation number counter for the
- % |\rndeqno| and |\rdeqno| 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}|. \\[1em]
- % \noindent|\rdeqno{FOO}|\\
- % 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. \\[1em]
- % \noindent|\where|\\
- % The command |\where| typsets the text ``where'' (in
- % the default LR-font) flush left on a seperate row in
- % |eqnarray|, |deqarr|, and |ddeqar| environments, and
- % preserves the environment's alignment for rows to come. \\[1em]
- % \noindent|\rem{|\textit{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|, and |ddeqar|
- % environments, and preserves the environment's alignment
- % for rows to come. |\where| is equivalent to
- % |\rem{where}|. \\[1em]
- % \noindent|\mthref{FOO}|\\
- % This is not intended as a user command, but is
- % avaliable. It is the same as ordinary |\ref{FOO}| but
- % does not type-set the `??' in |\bfseries| font if
- % occurring within mathmode. |deleq| makes use of this to
- % avoid interruptions when \LaTeX -ing documents
- % containing |\reqno|, |\rndeqno|, or |\rdeqno| with
- % undefined references. It can be used also outside
- % mathmode, and behaves then just like |\ref{FOO}|.
- % Warnings are the same as when using |\ref{FOO}|.
- % \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 |deleq| package. Typset it and see with
- % your own eyes what the results are!
- % \section{Sending a Bug Report}
- % |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:\\
- % \hspace*{5mm} \texttt{matsd@physchem.kth.se}.
- % \end{enumerate}
- % {\itshape Enjoy your \LaTeX!\raisebox{-\baselineskip}{mats d.}}
- % \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}[1994/06/01]
- \ProvidesPackage{deleq}[1994/12/27 v.4.1 Partial equation numbering]
- \typeout{deleq.sty included, version 4.1 (Dec. 27, 1994). (c) 1994 by Mats Dahlgren}
- \def\deleqver{\texttt{deleq} version 4.1 (Dec.~27, 1994)}
- % \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. Also the lettering of the counters are to be defined.
- % \begin{macrocode}
- \newcounter{deleq}[equation]
- \newcounter{Deleq}
- \newcount\@deqpen
- \newcount\@deqcnt
- \renewcommand{\thedeleq}{\ensuremath{\theequation\mathrm{\aLph{deleq}}}}
- \renewcommand{\theDeleq}{\ensuremath{\mathrm{\aLph{Deleq}}}}
- \def\@deleqnnum{(\thedeleq)}
- \def\aLph#1{\@aLph{\@nameuse{c@#1}}}
- \def\@aLph#1{\ifcase#1\or a\or b\or c\or d\or e\or f\or g\or h\or i\or j\or
- k\or l\or m\or n\or o\or p\or q\or r\or s\or t\or u\or v\or w\or x\or y\or
- z\else\@ctrerr\fi}
- % \end{macrocode}
- % The parts making up the |\\| command in the multiline environments
- % are extremely similar to those used by the standard environments:
- % \begin{macrocode}
- \def\@deqncr{{\ifnum0=`}\fi\@ifstar{\global\@deqpen\@M
- \@ydeqncr}{\global\@deqpen\interdisplaylinepenalty \@ydeqncr}}
- \def\@ydeqncr{\@ifnextchar [{\@xdeqncr}{\@xdeqncr[\z@]}}
- \def\@xdeqncr[#1]{\ifnum0=`{\fi}\@@deqncr
- \noalign{\penalty\@deqpen\vskip\jot\vskip #1\relax}}
- \def\@@deqncr{\let\@tempa\relax
- \ifcase\@deqcnt \def\@tempa{& & &}\or \def\@tempa{& &}%
- \else \def\@tempa{&}\fi
- \@tempa \if@eqnsw\@deleqnnum\stepcounter{deleq}\fi
- \global\@eqnswtrue\global\@deqcnt\z@\cr}
- % \end{macrocode}
- % \iffalse
- % Part 3: Commands: \nydeleqno, \deleqno, \reqno, \rndeqno, \rdeqno,
- % \nydeqno, and \heqno
- % \fi
- % \par Here the definitions of the user commands are.
- % \begin{macrocode}
- \newcommand{\nydeleqno}{\refstepcounter{equation}\refstepcounter{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{\nydeqno}{\stepcounter{equation}\stepcounter{deleq}}
- \newcommand{\heqno}{\stepcounter{equation}}
- % \end{macrocode}
- % And the two commands |\where| and |\rem| follow suit:
- % \begin{macrocode}
- \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', and 'ddeqn'
- % \fi
- % \par The four 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.
- % \begin{macrocode}
- \newenvironment{deqarr}{\stepcounter{equation}\stepcounter{deleq}
- \let\@currentlabel\thedeleq
- \global\@eqnswtrue\m@th
- \global\@deqcnt\z@\tabskip\@centering\let\\\@deqncr
- $$\halign to\displaywidth\bgroup\@eqnsel\hskip\@centering
- $\displaystyle\tabskip\z@{##}$&\global\@deqcnt\@ne
- \hskip 2\arraycolsep \hfil${##}$\hfil
- &\global\@deqcnt\tw@ \hskip 2\arraycolsep $\displaystyle\tabskip\z@{##}$\hfil
- \tabskip\@centering&\llap{##}\tabskip\z@\cr}
- {\@@deqncr\egroup
- \global\advance\c@deleq\m@ne$$\global\@ignoretrue}
- \newenvironment{ddeqar}{\stepcounter{deleq}
- \let\@currentlabel\thedeleq
- \global\@eqnswtrue\m@th
- \global\@deqcnt\z@\tabskip\@centering\let\\\@deqncr
- $$\halign to\displaywidth\bgroup\@eqnsel\hskip\@centering
- $\displaystyle\tabskip\z@{##}$&\global\@deqcnt\@ne
- \hskip 2\arraycolsep \hfil${##}$\hfil
- &\global\@deqcnt\tw@ \hskip 2\arraycolsep $\displaystyle\tabskip\z@{##}$\hfil
- \tabskip\@centering&\llap{##}\tabskip\z@\cr}
- {\enddeqarr}
- \newenvironment{deqn}{$$\refstepcounter{equation}\stepcounter{deleq}
- \let\@currentlabel\thedeleq}
- {\eqno \hbox{\@deleqnnum} $$\global\@ignoretrue}
- \newenvironment{ddeqn}{$$\refstepcounter{deleq} \let\@currentlabel\thedeleq}
- {\eqno \hbox{\@deleqnnum} $$\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:
- % \begin{macrocode}
- \DeclareOption{leqno}{\typeout{`leqno' implementation in progress.}
- \def\@deleqnnum{\hbox to .01\p@{}\rlap{\reset@font\rmfamily
- \hskip -\displaywidth(\thedeleq)}}
- \renewcommand{\nydeleqno}{\refstepcounter{equation}\refstepcounter{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)}
- % \end{macrocode}
- % If other options were asked for, the package should inform the user
- % that this has no effect on |deleq|. Then, last, the option(s)
- % is (are) processed.
- % \begin{macrocode}
- \DeclareOption*{\typeout{`\CurrentOption '\space has no effect on deleq.}%
- \OptionNotUsed}
- \ProcessOptions
- % \end{macrocode}
- % \iffalse
- % END of it all!
- %</paketkod>
- %<*driver>
- \documentclass[a4paper]{article}
- \usepackage{doc}
- \textwidth=150mm
- \textheight=210mm
- \topmargin=0mm
- \oddsidemargin=5mm
- \evensidemargin=5mm
- \begin{document}
- \DocInput{deleq.dtx}
- \PrintChanges
- \end{document}
- %</driver>
- %<*exempelkod>
- \documentclass[11pt]{article} %%% add `leqno' if you want left-aligned
- \usepackage{deleq} %%% equation numbers.
- \oddsidemargin=0.5cm
- \evensidemargin=0.5cm
- \topmargin=-5mm
- \textheight=23.5cm
- \textwidth=15.5cm
- \begin{document}
- \begin{center}
- \Large Welcome to the \texttt{deleq} package!
- \end{center}
- This is a short document to demonstrate the use of the
- \texttt{deleq} package and its commands. It uses \deleqver .
- \texttt{deleq} was written by Mats Dahlgren
- (\texttt{matsd@physchem.kth.se}). Suggestions for
- improvements and bug reports are most welcome, see the
- documentation. \texttt{deleq} is fully compatible with the
- \texttt{leqno} 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 \\
- \cos ( \alpha - \beta ) & =
- & \cos \alpha \cos \beta + \sin \alpha \sin \beta
- \end{ddeqar}
- 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{Demo2} \\
- \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{Demo2}. 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 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{Demo3} \\
- \tan \alpha & =
- & \frac{\sin \alpha}{\cos \alpha}
- \end{eqnarray}
- The upper equation was given the label \texttt{Demo3}.
- Now one of the ``recycling'' commands is to be
- demonstrated. First of all, let's make an ordinary
- reference to equation~\ref{Demo2}, and then ``recycle'' it:
- $$ \sin 2\alpha = 2 \sin \alpha \cos \alpha \reqno{Demo2} $$
- This was obtained with \verb#$$ ... $$# with the command
- \verb#\reqno{Demo2}# at the end. Also partially
- numbered equations can be recycled with the
- \verb#\reqno{FOO}# command, as with
- equation~\ref{Demo1}:
- $$ \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 $$
- Now we will elaborate a little on \verb#\rndeqno{FOO}#
- and \verb#\rdeqno{FOO}#. Let us use
- equation~\ref{Demo3}, and see what happens if we use the
- \verb#\rndeqno{FOO}# command:
- $$ \tan ^2 \alpha = \frac{\sin ^2 \alpha}
- {\cos ^2 \alpha} \rndeqno{Demo3} $$
- which we rewrite:
- $$ \tan ^2 \alpha = \frac{\sin ^2 \alpha}
- {1 - \sin ^2 \alpha} \rdeqno{Demo3} \label{Demo4} $$
- with \verb#\rdeqno{Demo3}# at the end. This is great
- fun, so why not one more:
- $$ \tan ^2 \alpha = \frac{1 - \cos ^2 \alpha}
- {\cos ^2 \alpha} \rdeqno{Demo3} $$
- Also, the middle form of equation~\ref{Demo3} got a
- label, \texttt{Demo4}.
- 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{Demo4}#,
- this is what \LaTeX\ will return:~\ref{Demo4}. That is
- not too instructive, since the partial equation numbers
- are quite common in this document. To make the complete
- reference, use \verb#\ref{Demo3}\ref{Demo4}#. The
- reference~\ref{Demo3}\ref{Demo4} is much more
- comprehensible, right? (If you get bad line-breaks at
- such references, put them in an \verb#\mbox{...}#.)
- Finally, the $\mathcal{END}$! If you want your
- equations 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
-