interfaces/emacs/imaxima/breqn097a/breqn.sty

   1 %%
   2 %% This is file `breqn.sty',
   3 %% generated with the docstrip utility.
   4 %%
   5 %% The original source files were:
   6 %%
   7 %% breqn.dtx  (with options: `package')
   8 %%
   9 %% This is a generated file.
  10 %%
  11 %% Copyright (C) 1997-2003 by Michael J. Downes
  12 %% Copyright (C) 2007 by Morten Hoegholm <mh.ctan@gmail.com>
  13 %%
  14 %% This work may be distributed and/or modified under the
  15 %% conditions of the LaTeX Project Public License, either
  16 %% version 1.3 of this license or (at your option) any later
  17 %% version. The latest version of this license is in
  18 %%    http://www.latex-project.org/lppl.txt
  19 %% and version 1.3 or later is part of all distributions of
  20 %% LaTeX version 2005/12/01 or later.
  21 %%
  22 %% This work has the LPPL maintenance status "maintained".
  23 %%
  24 %% This Current Maintainer of this work is Morten Hoegholm.
  25 %%
  26 %% This work consists of the main source file breqn.dtx
  27 %% and the derived files
  28 %%    breqn.sty, breqn.pdf, breqn.ins, breqn.drv.
  29 %%
  30 \NeedsTeXFormat{LaTeX2e}
  31 \ProvidesPackage{breqn}[2007/12/22 v0.97a]
  32 \edef\breqnpopcats{%
  33   \catcode\number`\"=\number\catcode`\"
  34   \relax}
  35 \AtEndOfPackage{\breqnpopcats}%
  36 \catcode`\^=7 \catcode`\_=8 \catcode`\"=12 \relax
  37 \DeclareOption{mathstyleoff}{%
  38   \PassOptionsToPackage{mathstyleoff}{flexisym}%
  39 }
  40 \ProcessOptions\relax
  41 \@ifpackageloaded{flexisym}{}{%
  42   \RequirePackage{flexisym}[2007/12/19]
  43     \edef\breqnpopcats{\breqnpopcats
  44     \catcode\number`\^=\number\catcode`\^
  45     \catcode\number`\_=\number\catcode`\_
  46   }%
  47   \catcode`\^=7 \catcode`\_=8 \catcode`\"=12 \relax
  48 }
  49 \RequirePackage{keyval,calc}\relax
  50 \@ifundefined{options}{%
  51 \newcommand{\options}[2]{%
  52   \expandafter\options@a\csname opt@#1.sty\endcsname{#2}%
  53   \setkeys{#1}{#2}%
  54 }
  55 \def\options@a#1#2{%
  56   \edef\@tempa{\options@b#2,\@empty\@nil}%
  57   \ifx#1\relax \let#1\@empty\fi
  58   \xdef#1{#1\ifx#1\@empty\@xp\@gobble\@tempa\@empty\else\@tempa \fi}%
  59 }
  60 \def\options@b#1,#2#3\@nil{%
  61   \options@c#1 \@nil
  62   \ifx#2\@empty \else\options@b#2#3\@nil\fi
  63 }
  64 \def\options@c#1 #2\@nil{\options@d#1=\@nil}
  65 \def\options@d#1=#2\@nil{\ifx\@empty #1\@empty\else,\fi#1}
  66 }{}% end @ifundefined test
  67 \let\@nx\noexpand
  68 \let\@xp\expandafter
  69 \@ifundefined{@emptytoks}{\newtoks\@emptytoks}{}
  70 \chardef\f@ur=4
  71 \newcount\inf@bad \inf@bad=1000000
  72 \newcount\maxint \maxint=2147483647
  73 \let\int@a=\@tempcnta
  74 \let\int@b=\@tempcntb
  75 \let\int@c=\count@
  76 \let\dim@a\@tempdima
  77 \let\dim@b\@tempdimb
  78 \let\dim@c\@tempdimc
  79 \let\dim@d\dimen@
  80 \let\dim@e\dimen@ii
  81 \let\dim@A\dimen@i
  82 \let\skip@a\@tempskipa
  83 \let\skip@b\@tempskipb
  84 \let\skip@c\skip@
  85 \let\toks@a\@temptokena
  86 \let\toks@b\toks@
  87 \toksdef\toks@c=2
  88 \toksdef\toks@d=4
  89 \toksdef\toks@e=6
  90 \toksdef\toks@f=8
  91 \def\abs@num#1{\ifnum#1<\z@-\fi#1}
  92 \def\@ifnext#1#2#3{%
  93   \let\@tempd= #1\def\@tempa{#2}\def\@tempb{#3}%
  94   \futurelet\@tempc\@ifnexta
  95 }
  96 \def\@ifnexta{\ifx\@tempc\@tempd \let\@tempb\@tempa \fi \@tempb}
  97 \def\@ifstar#1#2{%
  98   \let\@tempd*\def\@tempa*{#1}\def\@tempb{#2}%
  99   \futurelet\@tempc\@ifnexta
 100 }
 101 \def\@optarg#1#2{\@ifnext[{#1}{#1[#2]}}
 102 \def\@True{00}
 103 \def\@False{01}
 104 \def\@Not#1{0\ifcase#11 \or\@xp 1\else \@xp 0\fi}
 105 \def\@And#1#2{0\ifcase#1#2 \@xp 0\else \@xp 1\fi}
 106 \def\@Or#1#2{0\ifnum#1#2<101 \@xp 0\else \@xp 1\fi}
 107 \def\theb@@le#1{\if#1 True\else False\fi}
 108 \def\freeze@glue#1{#11#1\relax}
 109 \def\z@rule{\vrule\@width\z@}% no \relax ! use with care
 110 \def\keep@glue{\z@rule\relax}
 111 \begingroup \catcode`\&=11
 112 \gdef\replicate#1{%
 113   \csname &\expandafter\replicate@a\romannumeral\number\number#1 000q\endcsname
 114 }
 115 \endgroup
 116 \long\def\replicate@a#1#2\endcsname#3{#1\endcsname{#3}#2}
 117 \begingroup \catcode`\&=11
 118 \long\gdef\&m#1#2{#1\csname &#2\endcsname{#1}}
 119 \endgroup
 120 \@xp\let\csname\string &q\endcsname\@gobble
 121 \g@addto@macro\mathchars@reset{%
 122   \let\@symRel\@secondoftwo \let\@symBin\@secondoftwo
 123   \let\@symDeL\@secondoftwo \let\@symDeR\@secondoftwo
 124   \let\@symDeB\@secondoftwo
 125 }
 126 \def\eq@cons#1#2{%
 127   \begingroup \let\@elt\relax \xdef#1{\@elt{#2}#1}\endgroup
 128 }
 129 \providecommand{\@saveprimitive}[2]{%
 130   \begingroup
 131   \edef\@tempa{\string#1}\edef\@tempb{\meaning#1}%
 132   \ifx\@tempa\@tempb \global\let#2#1%
 133   \else
 134     \edef\@tempb{\meaning#2}%
 135     \ifx\@tempa\@tempb
 136     \else \@saveprimitive@a#1#2%
 137     \fi
 138   \fi
 139   \endgroup
 140 }
 141 \providecommand\@saveprimitive@a[2]{%
 142   \begingroup
 143   \def\@tempb##1#1##2{\edef\@tempb{##2}\@car{}}%
 144   \@tempb\nullfont{select font nullfont}%
 145     \topmark{\string\topmark:}%
 146     \firstmark{\string\firstmark:}%
 147     \botmark{\string\botmark:}%
 148     \splitfirstmark{\string\splitfirstmark:}%
 149     \splitbotmark{\string\splitbotmark:}%
 150     #1{\string#1}%
 151   \edef\@tempa{\expandafter\strip@prefix\meaning\@tempb}%
 152   \edef\@tempb{\meaning#1}%
 153   \ifx\@tempa\@tempb \global\let#2#1%
 154   \else
 155     \PackageError{breqn}%
 156       {Unable to properly define \string#2; primitive
 157       \noexpand#1no longer primitive}\@eha
 158     \fi
 159   \fi
 160   \endgroup
 161 }
 162 \begingroup \catcode`\$=\thr@@ % just to make sure
 163   \global\let\@@math=$ \gdef\@@display{$$}% $$$
 164 \endgroup
 165 \let\@@endmath=\@@math
 166 \let\@@enddisplay=\@@display
 167 \@saveprimitive\vadjust\@@vadjust
 168 \@saveprimitive\insert\@@insert
 169 \@saveprimitive\mark\@@mark
 170 \@ifundefined{listwidth}{\newdimen\listwidth}{}
 171 \listwidth=\z@
 172 \def\eqfontsize{}         % Inherit from context    [NOT USED?]
 173 \def\eqcolor{black}       % Default to black        [NOT USED?]
 174 \newdimen\eqnumsep \eqnumsep=10pt        % Min space between equ number and body
 175 \newdimen\eqmargin \eqmargin=8pt         % For `multline' gap emulation
 176 \def\eqindent{C}%         % C or I, centered or indented
 177 \def\eqnumside{R}%        % R or L, right or left
 178 \def\eqnumplace{M}%       % M or T or B, middle top or bottom
 179 \def\eqnumfont{}%         % Null for easier debugging [mjd,1997/09/26]
 180 \def\eqnumform#1{(#1\@@italiccorr)} % Add parens
 181 \def\eqnumsize{}          % Allow numbers to have different typesize ...
 182 \def\eqnumcolor{}         % ... or color than eq body e.g. \color{blue}
 183 \newlength\eqlinespacing \eqlinespacing=14pt plus2pt % Base-to-base space between lines
 184 \newlength\eqlineskip \eqlineskip=3pt plus2pt % Min space if eqlinespacing too small
 185 \newdimen\eqlineskiplimit \eqlineskiplimit=2pt  % Threshold for switching to eqlineskip
 186 \newmuskip \eqbinoffset \eqbinoffset=15mu minus-3mu % Offset from mathrel alignment pt for mathbins
 187 \newmuskip\eqdelimoffset \eqdelimoffset=2mu    % Additional offset for break inside delims
 188 \newdimen\eqindentstep \eqindentstep=8pt     % Indent used when LHS wd is n/a or too large
 189 \newtoks\eqstyle           % Customization hook
 190 \newcount\eqbreakdepth \eqbreakdepth=2       % Allow breaks within delimiters to this depth
 191 \newcount \eqinterlinepenalty \eqinterlinepenalty=10000 % No page breaks between equation lines
 192 \newcount \intereqpenalty \intereqpenalty=1000   % Pagebreak penalty between equations [BRM: Was \@M]
 193 \newlength \intereqskip \intereqskip=3pt plus2pt % Additional vert space between equations
 194 \newcount\prerelpenalty \prerelpenalty=-\@M   % Linebreak penalty before mathrel symbols
 195 \newcount\prebinoppenalty \prebinoppenalty=888  % Linebreak penalty before mathbins
 196 \newmuskip \Dmedmuskip \Dmedmuskip=4mu minus 3mu % medmuskip in displays
 197 \newmuskip \Dthickmuskip \Dthickmuskip=5mu minus 2mu % thickmuskip in displays
 198 \def\eq@number{}          % Internal variable
 199 \newlength\eqleftskip \eqleftskip=\@centering  % Space on the left  [NOT USED?]
 200 \newlength\eqrightskip \eqrightskip=\@centering % Space on the right [NOT USED?]
 201 \newlength\eq@vspan \eq@vspan=\z@skip     % Glue used to vcenter the eq number
 202 \newmuskip\eq@binoffset \eq@binoffset=\eqbinoffset % Roughly, \eqbinoffset + \eqdelimoffset
 203 \newsavebox\EQ@box               % Storage for equation body
 204 \newsavebox\EQ@copy              % For eq body sans vadjust/insert/mark material
 205 \newsavebox\EQ@numbox            % For equation number
 206 \newdimen\eq@wdNum         % width of number + separation [NEW]
 207 \newsavebox\GRP@numbox            % For group number [NEW]
 208 \newdimen\grp@wdNum         % width of number + separation [NEW]
 209 %%B\EQ@vimbox            % Vadjust, insert, or mark material
 210 %%B\EQ@vimcopy           % Spare copy of same
 211 %%B\eq@impinging         % Temporary box for measuring number placement
 212 \newcount \eq@lines          % Internal counter, actual number of lines
 213 \newcount \eq@curline       % Loop counter
 214 \newcount \eq@badness      % Used in testing for overfull lines
 215 \newcount \EQ@vims          % For bookkeeping
 216 \def\@eq@numbertrue{\let\eq@hasNumber\@True}%
 217 \def\@eq@numberfalse{\let\eq@hasNumber\@False}%
 218 \let\eq@hasNumber\@False
 219 \newdimen\eq@dp         % Depth of last line
 220 \newdimen\eq@wdL        % Width of the left-hand-side
 221 \newdimen\eq@wdT        % Total width for framing
 222 \newdimen\eq@wdMin      % Width of narrowest line in equation
 223 \newdimen\grp@wdL       % Max width of LHS's in a group
 224 \newdimen\grp@wdR       % Max RHS of all equations in a group
 225 \newdimen\grp@wdT
 226 \newdimen\eq@wdRmax
 227 \newdimen\eq@firstht    % Height of first line
 228 \newdimen\eq@wdCond
 229 \newdimen\eq@indentstep % Indent amount when LHS is not present
 230 \newdimen\eq@linewidth  % Width actually used for display
 231 \newdimen\grp@linewidth % Max eq@linewidth over a group
 232 \newdimen\eq@hshift
 233 \let\eq@isIntertext\@False
 234 \eq@indentstep=\maxdimen
 235 \newdimen\eq@given@sidespace
 236 \def\eq@overrun{0pt}
 237 \@ifpackagewith{amsmath}{leqno}{%
 238   \@ifpackagewith{amsmath}{reqno}{}{\def\eqnumside{L}}%
 239 }{%
 240   \def\@tempa#1,leqno.clo,#2#3\@nil{%
 241     \ifx @#2\relax\else \def\eqnumside{L}\fi
 242   }%
 243   \@xp\@tempa\@filelist,leqno.clo,@\@nil
 244   \if L\eqnumside
 245   \else
 246     \@ifundefined{iftagsleft@}{}{%
 247       \edef\eqnumside{%
 248         \if TT\csname fi\endcsname\csname iftagsleft@\endcsname
 249           L\else R\fi
 250       }%
 251     }
 252   \fi
 253 }
 254 \@ifpackagewith{amsmath}{fleqn}{%
 255   \def\eqindent{I}%
 256 }{%
 257   \def\@tempa#1,fleqn.clo,#2#3\@nil{%
 258     \ifx @#2\relax\else \def\eqindent{I}\fi
 259   }%
 260   \@xp\@tempa\@filelist,fleqn.clo,@\@nil
 261   \if I\eqindent
 262   \else
 263     \@ifundefined{if@fleqn}{}{%
 264       \edef\eqindent{%
 265         \if TT\csname fi\endcsname\csname if@fleqn\endcsname
 266           I\else C\fi
 267       }%
 268     }%
 269   \fi
 270 }
 271   \@ifundefined{mathindent}{%
 272     \newdimen\mathindent
 273   }{%
 274     \@ifundefined{@mathmargin}{}{%
 275       \mathindent\@mathmargin
 276     }%
 277   }
 278 \let\EQ@hasLHS=\@False
 279 \let\EQ@QED=\@empty
 280 \def\mark@lhs#1{%
 281   \ifnum\lr@level<\@ne
 282     \let\mark@lhs\relax
 283     \global\let\EQ@hasLHS=\@True
 284     \global\let\EQ@prebin@space\EQ@prebin@space@a
 285     \mark@lhs@a
 286     \penalty9999 % instead of normal \rel@break
 287   % else no penalty = forbid break
 288   \fi
 289 }
 290 \def\mark@lhs@a{%
 291   \mskip\thickmuskip \@@vadjust{\penalty\tw@}\penalty-\@Mi\@@vadjust{}%
 292 }
 293 \newcommand\hiderel[1]{\mathrel{\advance\lr@level\@ne#1}}
 294 \let\m@@Bin\m@Bin
 295 \let\m@@Rel\m@Rel
 296 \let\EQ@prebin@space\relax
 297 \def\EQ@prebin@space@a{\mskip-\eq@binoffset \keep@glue \mskip\eq@binoffset}
 298 \def\bin@break{\ifnum\lastpenalty=\z@\penalty\prebinoppenalty\fi
 299   \EQ@prebin@space}
 300 \def\rel@break{%
 301   \ifnum\abs@num\lastpenalty <\abs@num\prerelpenalty
 302     \penalty\prerelpenalty
 303   \fi
 304 }
 305 \def\d@@Bin{\bin@break \m@@Bin}
 306 \def\d@@Rel{\mark@lhs \rel@break \m@@Rel}
 307 \let\m@@symRel\@symRel \def\d@@symRel{\mark@lhs \rel@break \m@@symRel}
 308 \let\m@@symBin\@symBin \def\d@@symBin{\bin@break \m@@symBin}
 309 \let\m@@symDel\@symDel
 310 \let\m@@symDeR\@symDeR
 311 \let\m@@symDeB\@symDeB
 312 \let\m@@symDeA\@symDeA
 313 \def\display@setup{%
 314   \medmuskip\Dmedmuskip \thickmuskip\Dthickmuskip
 315   \let\m@Bin\d@@Bin \let\m@Rel\d@@Rel
 316   \let\@symRel\d@@symRel \let\@symBin\d@@symBin
 317   \let\m@DeL\d@@DeL \let\m@DeR\d@@DeR \let\m@DeB\d@@DeB
 318   \let\m@DeA\d@@DeA
 319   \let\@symDeL\d@@symDeL \let\@symDeR\d@@symDeR
 320   \let\@symDeB\d@@symDeB \let\@symDeA\d@@symDeA
 321   \let\left\eq@left \let\right\eq@right \global\lr@level\z@
 322   \global\eq@wdCond\z@          %BRM: new
 323   \everyhbox{\everyhbox\@emptytoks
 324     \let\display@setup\relax \textmath@setup \let\textmath@setup\relax
 325   }%
 326   \everyvbox{\everyvbox\@emptytoks
 327     \let\display@setup\relax \textmath@setup \let\textmath@setup\relax
 328   }%
 329 }
 330 \def\dseries@display@setup{%
 331   \medmuskip\Dmedmuskip \thickmuskip\Dthickmuskip
 332   \let\m@Bin\d@@Bin
 333  \let\@symBin\d@@symBin
 334   \let\m@DeL\d@@DeL \let\m@DeR\d@@DeR \let\m@DeB\d@@DeB
 335   \let\m@DeA\d@@DeA
 336   \let\@symDeL\d@@symDeL \let\@symDeR\d@@symDeR
 337   \let\@symDeB\d@@symDeB \let\@symDeA\d@@symDeA
 338   \let\left\eq@left \let\right\eq@right \global\lr@level\z@
 339   \everyhbox{\everyhbox\@emptytoks
 340     \let\display@setup\relax \textmath@setup \let\textmath@setup\relax
 341   }%
 342   \everyvbox{\everyvbox\@emptytoks
 343     \let\display@setup\relax \textmath@setup \let\textmath@setup\relax
 344   }%
 345  \displaystyle
 346 }
 347 \def\textmath@setup{%
 348   \let\m@Bin\m@@Bin \let\m@Rel\m@@Rel
 349   \let\@symRel\m@@symRel \let\@symBin\m@@symBin
 350   \let\m@DeL\m@@DeL \let\m@DeR\m@@DeR \let\m@DeB\m@@DeB
 351   \let\m@DeA\m@@DeA
 352   \let\@symDeL\m@@symDeL \let\@symDeR\m@@symDeR
 353   \let\@symDeB\m@@symDeB \let\@symDeA\m@@symDeA
 354   \let\left\@@left \let\right\@@right
 355 }
 356 \@ifundefined{@displaytrue}{%
 357   \@xp\newif\csname if@display\endcsname
 358   \everydisplay\@xp{\the\everydisplay \@displaytrue}%
 359 }{}
 360 \define@key{breqn}{label}{\def\next@label{\label{#1}}}
 361 \global\let\next@label\@empty
 362 \define@key{breqn}{number}{\def\eq@number{#1}%
 363   \let\@currentlabel\eq@number
 364 }
 365 \define@key{breqn}{shiftnumber}{\let\eq@shiftnumber\@True}
 366 \define@key{breqn}{holdnumber}{\let\eq@holdnumber\@True}
 367 \define@key{breqn}{density}{\def\eq@density@factor{#1}}
 368 \define@key{breqn}{indentstep}{\eqindentstep#1\relax}
 369 \define@key{breqn}{compact}[-99]{\prerelpenalty=#1\relax}
 370 \define@key{breqn}{layout}[?]{%
 371   \edef\eq@layout{\@car#1?\@nil}%
 372 }
 373 \define@key{breqn}{spread}{%
 374   \addtolength\eqlinespacing{#1}%
 375   \addtolength\eqlineskip{#1}%
 376   \eqlineskiplimit\eqlineskip
 377 }
 378 \define@key{breqn}{sidespace}{%
 379   \setlength\eq@given@sidespace{#1}%
 380 }
 381 \define@key{breqn}{style}{\eqstyle\@xp{\the\eqstyle #1}}
 382 \define@key{breqn}{shortskiplimit}{\def\eq@shortskiplimit{#1}}
 383 \def\eq@shortskiplimit{2em}
 384 \define@key{breqn}{frame}[\fboxrule]{\def\eq@frame{T}%
 385   \dim@a#1\relax\edef\eq@framewd{\the\dim@a}%
 386   \freeze@glue\eqlinespacing \freeze@glue\eqlineskip
 387 }
 388 \define@key{breqn}{fullframe}[]{\def\eq@frame{U}%
 389   \freeze@glue\eqlinespacing \freeze@glue\eqlineskip
 390 }
 391 \def\eq@frame{F} % no frame
 392 \def\eq@framewd{\fboxrule}
 393 \define@key{breqn}{framesep}[\fboxsep]{%
 394   \if\eq@frame F\def\eq@frame{T}\fi
 395   \dim@a#1\relax \edef\eq@framesep{\the\dim@a}%
 396   \freeze@glue\eqlinespacing \freeze@glue\eqlineskip
 397 }
 398 \def\eq@framesep{\fboxsep}
 399 \define@key{breqn}{background}{\def\eq@background{#1}%
 400   \freeze@glue\eqlinespacing \freeze@glue\eqlineskip
 401 }
 402 \define@key{breqn}{color}{\def\eq@foreground{#1}}
 403 \define@key{breqn}{center}[]{\let\eq@centerlines\@True}
 404 \define@key{breqn}{nocenter}[]{\let\eq@centerlines\@False}
 405 \let\eq@centerlines\@False
 406 \define@key{breqn}{noalign}[]{\let\grp@aligned\@False}
 407 \let\grp@aligned\@True % default
 408 \define@key{breqn}{breakdepth}{\eqbreakdepth#1\relax}
 409 \define@key{breqn}{cols}{\global\let\@preamble\@empty
 410   \darray@mkpream#1\@percentchar
 411 }
 412 \newenvironment{dmath}{%
 413  \let\eq@hasNumber\@True \@optarg\@dmath{}}{}
 414 \def\@dmath[#1]{%
 415   \everydisplay\expandafter{\the\everydisplay \display@setup}%
 416   \if@noskipsec \leavevmode \fi
 417   \if@inlabel \leavevmode \global\@inlabelfalse \fi
 418   \if\eq@group\else\eq@prelim\fi
 419   \setkeys{breqn}{#1}%
 420   \the\eqstyle
 421   \eq@setnumber
 422   \begingroup
 423   \eq@setup@a
 424   \eq@startup
 425 }
 426 \def\enddmath#1{\check@punct@or@qed}
 427 \def\end@dmath{%
 428   \gdef\EQ@setwdL{}% Occasionally undefined ???
 429   \eq@capture
 430   \endgroup
 431   \EQ@setwdL
 432   \eq@measure
 433   \if\eq@group \grp@push \else \eq@finish\fi
 434 }
 435 \newenvironment{dmath*}{%
 436   \let\eq@hasNumber\@False \@optarg\@dmath{}%
 437 }{}
 438 \@namedef{end@dmath*}{\end@dmath}
 439 \@namedef{enddmath*}#1{\check@punct@or@qed}
 440 \def\eq@prelim{%
 441   \if@inlabel \indent \par \fi
 442   \if@nobreak \global\@nobreakfalse \predisplaypenalty\@M \fi
 443   \everypar\@emptytoks
 444   \noindent
 445   \eq@nulldisplay
 446   \par %% \eq@saveparinfo %% needs work
 447   \let\intertext\breqn@intertext
 448 }
 449 \def\breqn@parshape@warning{%
 450   \PackageWarning{breqn}{%
 451     Complex paragraph shape cannot be followed by this equation}%
 452 }
 453 \let\eq@prevshape\@empty
 454 \def\eq@saveparinfo{%
 455   \count@\prevgraf \advance\count@-\thr@@ % for the null display
 456   \edef\eq@prevshape{\prevgraf\the\count@\space}%
 457   \ifcase\parshape
 458     % case 0: no action required
 459   \or \edef\eq@prevshape{\eq@prevshape
 460         \parshape\@ne\displayindent\displaywidth\relax
 461       }%
 462   \else
 463     \breqn@parshape@warning
 464   \fi
 465 }
 466 \def\eq@setnumber{%
 467   \eq@wdNum\z@
 468   \if\eq@hasNumber
 469     \ifx\eq@number\@empty
 470       \stepcounter{equation}\let\eq@number\theequation
 471     \fi
 472  % This sets up numbox, etc, even if unnumbered?????
 473     \ifx\eq@number\@empty
 474     \else
 475       \set@label{equation}\eq@number
 476       \global\sbox\EQ@numbox{%
 477         \next@label \global\let\next@label\@empty
 478         \eqnumcolor\eqnumsize\eqnumfont{\eqnumform{\eq@number}}%
 479       }%
 480       \global\eq@wdNum\wd\EQ@numbox\global\advance\eq@wdNum\eqnumsep
 481     \fi
 482   \fi
 483 }
 484 \newcount\eq@final@linecount
 485 \let\eq@GRP@first@dmath\@True
 486 \def\eq@finish{%
 487   \begingroup
 488     \if F\eq@frame\else
 489       \freeze@glue\eqlinespacing \freeze@glue\eqlineskip
 490     \fi
 491     \csname eq@\eqindent @setsides\endcsname % Compute \leftskip,\rightskip
 492     \adjust@parshape\eq@parshape% Final adjustment of parshape for left|right skips
 493     \if\eq@group
 494       \if\eq@GRP@first@dmath
 495         \global\let\eq@GRP@first@dmath\@False
 496         \xdef\dmath@first@leftskip{\leftskip=\the\leftskip\relax}%
 497       \else
 498         \eq@topspace{\vskip\parskip}% Set top spacing
 499       \fi
 500     \else
 501       \eq@topspace{\vskip\parskip}% Set top spacing
 502     \fi
 503     \afterassignment\remove@to@nnil
 504     \eq@final@linecount=\expandafter\@gobble\eq@parshape\@nnil
 505     \if\eq@hasNumber
 506       \if\eq@shiftnumber
 507         \csname eq@typeset@\eqnumside Shifted\endcsname
 508       \else
 509         \ifnum\eq@final@linecount=\@ne
 510           \csname eq@typeset@\eqnumside @single\endcsname
 511         \else
 512           \csname eq@typeset@\eqnumside\eqnumplace\endcsname
 513         \fi
 514       \fi
 515     \else
 516       \eq@typeset@Unnumbered
 517     \fi
 518   \endgroup
 519   \eq@botspace
 520 }
 521 \def\eq@typeset@L@single{%
 522   \nobreak
 523   \eq@params\eq@parshape
 524   \nointerlineskip\noindent
 525   \add@grp@label
 526   \rlap{\kern-\leftskip\box\EQ@numbox}%
 527   \if F\eq@frame
 528   \else
 529     \rlap{\raise\eq@firstht\hbox to\z@{\eq@addframe\hss}}%
 530   \fi
 531   \eq@dump@box\unhbox\EQ@box \@@par
 532 }
 533 \def\eq@typeset@R@single{%
 534   \nobreak
 535   \eq@params\eq@parshape
 536   \nointerlineskip\noindent
 537   \add@grp@label
 538   \if F\eq@frame
 539   \else
 540     \rlap{\raise\eq@firstht\hbox to\z@{\eq@addframe\hss}}%
 541   \fi
 542   \rlap{\kern-\leftskip\kern\linewidth\kern-\wd\EQ@numbox\copy\EQ@numbox}%
 543   \eq@dump@box\unhbox\EQ@box
 544   \@@par
 545 }
 546 \def\peek@branch#1#2{%
 547   \let\peek@b#1\let\peek@space#2\futurelet\@let@token\peek@a
 548 }
 549 \def\peek@skipping@spaces#1{\peek@branch#1\peek@skip@space}
 550 \def\peek@a{%
 551   \ifx\@let@token\@sptoken \expandafter\peek@space
 552   \else \expandafter\peek@b\fi
 553 }
 554 \lowercase{\def\peek@skip@space} {\futurelet\@let@token\peek@a}%
 555 \def\check@punct{\futurelet\@let@token\check@punct@a}
 556 \def\check@punct@a{%
 557   \edef\@tempa{%
 558     \ifx\@let@token\@sptoken\@nx\finish@end
 559     \else\ifx\@let@token ,\@nx\check@qed
 560     \else\ifx\@let@token .\@nx\check@qed
 561     \else\check@punct@b % check the less common possibilities
 562     \fi\fi\fi
 563   }%
 564   \@tempa
 565 }
 566 \begingroup
 567 \toks@a{%
 568   \ifx\@let@token ;\@nx\check@qed
 569   \else\ifx\@let@token ?\@nx\check@qed
 570   \else\ifx\@let@token !\@nx\check@qed
 571 }
 572 \toks@c{\fi\fi\fi}% matching with \toks@a
 573 \catcode`\.=\active \catcode`\,=\active \catcode`\;=\active
 574 \catcode`\?=\active \catcode`\!=\active
 575 \toks@b{%
 576   \else\ifx\@let@token ,\@nx\check@qed
 577   \else\ifx\@let@token .\@nx\check@qed
 578   \else\ifx\@let@token ;\@nx\check@qed
 579   \else\ifx\@let@token ?\@nx\check@qed
 580   \else\ifx\@let@token !\@nx\check@qed
 581   \else\@nx\finish@end
 582   \fi\fi\fi\fi\fi
 583 }
 584 \xdef\check@punct@b{%
 585   \the\toks@a\the\toks@b\the\toks@c
 586 }
 587 \endgroup
 588 \let\found@punct\@empty
 589 \def\check@qed#1{%
 590   \gdef\found@punct{#1}%
 591   \peek@skipping@spaces\check@qed@a
 592 }
 593 \def\check@qed@a{%
 594   \ifx\end\@let@token \@xp\check@qed@b
 595   \else \@xp\finish@end
 596   \fi
 597 }
 598 \def\check@qed@b#1#2{%
 599   \@ifundefined{#2qed}{}{%
 600     \toks@\@xp{\found@punct\csname#2qed\endcsname}%
 601     \xdef\found@punct{\the\toks@}%
 602   }%
 603   \finish@end
 604   \end{#2}%
 605 }
 606 \def\@tempa#1\endcsname#2\@nil{\def\latex@end##1{#2}}
 607 \expandafter\@tempa\end{#1}\@nil
 608 \def\end#1{\csname end#1\endcsname \latex@end{#1}}%
 609 \def\check@punct@or@qed#1{%
 610   \xdef\found@punct{\@empty}% BRM: punctuation was being remembered past this eqn.
 611   \def\finish@end{\csname end@#1\endcsname\latex@end{#1}}%
 612   \check@punct
 613 }
 614 \newcommand\eqpunct[1]{\thinspace#1}
 615 \providecommand\set@label[2]{\protected@edef\@currentlabel{#2}}
 616 \def\eq@topspace#1{%
 617   \begingroup
 618     \global\let\EQ@shortskips\@False
 619     \if\@And{\eq@group}{\@Not\eq@GRP@first@dmath}%
 620         \parskip\intereqskip \penalty\intereqpenalty
 621     \else
 622       \eq@check@shortskip
 623       \if\EQ@shortskips
 624         \parskip\abovedisplayshortskip
 625         \aftergroup\belowdisplayskip\aftergroup\belowdisplayshortskip
 626         \ifdim\predisplaysize>\z@\nointerlineskip\fi
 627       \else
 628         \parskip\abovedisplayskip
 629       \fi
 630     \fi
 631     \if F\eq@frame
 632     \else
 633       \addtolength\parskip{\eq@framesep+\eq@framewd}%
 634     \fi
 635     #1%
 636   \endgroup
 637 }
 638 \def\eq@check@shortskip {%
 639   \global\let\EQ@shortskips\@False
 640   \setlength\dim@a{\abovedisplayskip+\ht\EQ@numbox}%
 641   \ifdim\leftskip<\predisplaysize
 642   \else
 643     \ifdim -\maxdimen=\predisplaysize
 644     \else
 645       \if R\eqnumside
 646         \global\let\EQ@shortskips\@True
 647       \else
 648         \if\eq@shiftnumber
 649         \else
 650           \if T\eqnumplace
 651             \ifdim\dim@a<\eq@firstht
 652               \global\let\EQ@shortskips\@True
 653             \fi
 654           \else
 655             \setlength\dim@b{\eq@vspan/2}%
 656             \ifdim\dim@a<\dim@b
 657               \global\let\EQ@shortskips\@True
 658             \fi
 659           \fi
 660         \fi
 661       \fi
 662     \fi
 663   \fi
 664 }
 665 \def\eq@botspace{%
 666   \penalty\postdisplaypenalty
 667   \if F\eq@frame
 668   \else
 669     \addtolength\belowdisplayskip{\eq@framesep+\eq@framewd}%
 670   \fi
 671   \vskip\belowdisplayskip
 672   \@endpetrue % kill parindent if current paragraph continues
 673   \global\@ignoretrue % ignore following spaces
 674   \eq@resume@parshape
 675 }
 676 \def\eq@resume@parshape{}
 677 \def\eq@startup{%
 678   \global\let\EQ@hasLHS\@False
 679   \setbox\z@\vbox\bgroup
 680     \noindent \@@math \displaystyle
 681     \penalty-\@Mi
 682 }
 683 \def\eq@setup@a{%
 684   \everymath\everydisplay
 685   %\let\@newline\eq@newline % future possibility?
 686   \let\\\eq@newline
 687   \let\insert\eq@insert \let\mark\eq@mark \let\vadjust\eq@vadjust
 688   \hsize\maxdimen \pretolerance\@M
 689   \linepenalty\@m
 690   \rightskip\z@\@plus\@M\p@ \leftskip\z@skip \parfillskip\z@skip
 691   \clubpenalty\@ne \widowpenalty\z@ \interlinepenalty\z@
 692   \global\let\EQ@prebin@space\relax
 693   \binoppenalty\@M \relpenalty\@M
 694 }
 695 \newdimen\eq@wdR\eq@wdR\z@%BRM
 696 \def\eq@capture{%
 697   \ifnum\lastpenalty>-\@M \penalty-\@Mi \fi
 698   \keep@glue\@@endmath
 699   \eq@addpunct
 700   \@@par
 701   \eq@wdL\z@
 702   \setbox\tw@\lastbox
 703   \global\setbox\EQ@box\hbox{\unhbox\tw@\unskip\unskip\unpenalty}%
 704   \unskip\unpenalty
 705   \global\setbox\EQ@copy\copy\EQ@box
 706 %%  \global\setbox\EQ@vimcopy\copy\EQ@vimbox
 707   \clubpenalty\z@
 708   \eq@wdR\z@%BRM: eq@wdL patch
 709   \eq@repack % recursive
 710   \setbox\tw@\lastbox
 711   \global\setbox\EQ@box\hbox{\unhcopy\tw@\unskip\unpenalty \unhbox\EQ@box}%
 712   \global\setbox\EQ@copy\hbox{\unhbox\tw@\unskip\unpenalty \unhbox\EQ@copy}%
 713   \ifdim\eq@wdR>\z@% BRM:  eq@wdL patch
 714     \setlength\dim@a{\wd\EQ@box-\eq@wdR
 715     % Apparently missing a \thickmuskip = 5mu = 5/18em=0.27777777777.. ?
 716        + 0.2777777777777em}% FUDGE??!?!?!
 717     \ifdim\dim@a>\eq@wdL
 718       \eq@wdL\dim@a
 719       \xdef\EQ@setwdL{\eq@wdL\the\eq@wdL\relax}%
 720     \fi
 721   \fi
 722   \egroup % end vbox started earlier
 723 }
 724 \def\eq@addpunct{%
 725   \ifx\found@punct\@empty
 726   \else \eqpunct{\found@punct}%
 727   \fi
 728   % BRM: Added; the punctuation kept  getting carried to following environs
 729   \xdef\found@punct{\@empty}%
 730   \EQ@afterspace
 731 }
 732 \global\let\EQ@afterspace\@empty
 733 \def\eq@repack{%
 734   \ifcase\lastpenalty
 735      % case 0: normal case
 736     \setbox\tw@\lastbox
 737     \eq@repacka\EQ@copy \eq@repacka\EQ@box
 738     \unskip
 739   \or % case 1: finished recursing
 740     \unpenalty
 741     \setbox\tw@\lastbox
 742     \eq@repacka\EQ@copy \eq@repacka\EQ@box
 743     \@xp\@gobble
 744   \or % case 2: save box width = LHS width
 745     \unpenalty
 746     \setbox\tw@\lastbox
 747     \setbox\z@\copy\tw@ \setbox\z@\hbox{\unhbox\z@\unskip\unpenalty}%
 748     \addtolength\eq@wdL{\wd\z@}
 749     \setlength\eq@wdR{\wd\EQ@box}% BRM:  eq@wdL patch
 750     \xdef\EQ@setwdL{\eq@wdL\the\eq@wdL\relax}%
 751     \global\setbox\EQ@copy\hbox{%
 752       \hbox{\unhcopy\tw@\unskip\unpenalty\unskip}%
 753       \box\EQ@copy
 754     }%
 755     \global\setbox\EQ@box\hbox{%
 756       \hbox{\unhbox\tw@\unskip\unpenalty\unskip}%
 757       \box\EQ@box
 758     }%
 759     \unskip
 760   \or % case 3: unpack left-right box
 761     \unpenalty
 762     \eq@lrunpack
 763   \else
 764     \breqn@repack@err
 765   \fi
 766   \eq@repack % RECURSE
 767 }
 768 \def\breqn@repack@err{%
 769   \PackageError{breqn}{eq@repack penalty neq 0,1,2,3}\relax
 770 }
 771 \def\eq@repacka#1{%
 772   \global\setbox#1\hbox{\unhcopy\tw@ \unskip
 773     \count@-\lastpenalty
 774     \ifnum\count@<\@M \else \advance\count@-\@M \fi
 775     \unpenalty
 776     \ifx\EQ@copy#1\ifnum\count@>\thr@@ \count@\@ne\fi\fi
 777     \ifcase\count@
 778         % case 0, normal line break
 779       \penalty-\@M % put back the linebreak penalty
 780     \or % case 1, do nothing (end of equation)
 781       \relax
 782     \or % case 2, no-op (obsolete case)
 783     \or % case 3, transfer vspace and/or penalty
 784       \ifx#1\EQ@box \eq@revspace \else \eq@revspaceb \fi
 785     \or % case 4, put back an insert
 786       \eq@reinsert
 787     \or % case 5, put back a mark
 788       \eq@remark
 789     \or % case 6, put back a vadjust
 790       \eq@readjust
 791     \else % some other break penalty
 792       \penalty-\count@
 793     \fi
 794     \unhbox#1}%
 795 }
 796 \def\eq@nulldisplay{%
 797   \begingroup \frozen@everydisplay\@emptytoks
 798   \@@display
 799   \predisplaypenalty\@M \postdisplaypenalty\@M
 800   \abovedisplayskip\z@skip \abovedisplayshortskip\z@skip
 801   \belowdisplayskip\z@skip \belowdisplayshortskip\z@skip
 802   \xdef\EQ@displayinfo{%
 803     \prevgraf\the\prevgraf \predisplaysize\the\predisplaysize
 804     \displaywidth\the\displaywidth \displayindent\the\displayindent
 805     \listwidth\the\linewidth
 806     \ifdim\displayindent>\z@
 807       \advance\listwidth\the\leftmargin
 808       \advance\listwidth\the\rightmargin
 809     \fi
 810     \relax}%
 811   \halign{##\cr}%
 812   \@@enddisplay
 813   \par
 814   \endgroup
 815   \EQ@displayinfo
 816 }
 817 \def\eq@newline{%
 818   \@ifstar{\eq@newlinea\@M}{\eq@newlinea\eqinterlinepenalty}}
 819 \def\eq@newlinea#1{%
 820   \@ifnext[{\eq@newlineb{#1}}{\eq@newlineb{#1}[\maxdimen]}}
 821 \def\eq@newlineb#1[#2]{\penalty-\@M}
 822 \def\eq@revspace{%
 823   \global\setbox\EQ@vimbox\vbox{\unvbox\EQ@vimbox
 824     \unpenalty
 825     \global\setbox\@ne\lastbox}%
 826   \@@vadjust{\unvbox\@ne}%
 827   \penalty-\@M
 828 }
 829 \def\eq@revspaceb{%
 830   \global\setbox\EQ@vimcopy\vbox{\unvbox\EQ@vimcopy
 831     \unpenalty
 832     \global\setbox\@ne\lastbox}%
 833   \@@vadjust{\unvbox\@ne}%
 834   \penalty-\@M
 835 }
 836 \def\eq@break#1{\penalty-1000#1 \keep@glue}
 837 \let\@parshape\@empty
 838 \def\eq@measure{%
 839   \ifdim\eq@indentstep=\maxdimen \eq@indentstep\eqindentstep \fi
 840   \ifdim\eq@linewidth=\z@ \else \edef\eq@linewidths{{\the\eq@linewidth}}\fi
 841   \begingroup \eq@params
 842   \leftskip\z@skip
 843   \rightskip\z@\@plus\columnwidth\@minus\hfuzz
 844   \global\EQ@continue{\eq@trial}%
 845   \eq@trial % uses \eq@linewidths
 846   \eq@failout % will be a no-op if the trial succeeded
 847   \endgroup
 848   \EQ@trial
 849 }
 850 \let\EQ@trial\@empty
 851 \newtoks\EQ@continue
 852 \let\EQ@widths\@empty
 853 \let\EQ@fallback\@empty
 854 \def\eq@linewidths{\displaywidth\linewidth\columnwidth}
 855 \def\eq@trial{%
 856   \ifx\@empty\eq@linewidths
 857     \global\EQ@continue{}%
 858   \else
 859     \iffalse{\fi \@xp\eq@trial@a \eq@linewidths}%
 860   \fi
 861   \the\EQ@continue
 862 }
 863 \def\eq@trial@a#1{%
 864   \dim@c#1\relax
 865   \if T\eq@frame \eq@frame@adjust\dim@c \fi
 866   \ifdim\dim@c>\eq@linewidth
 867     \eq@linewidth\dim@c
 868     \let\eq@trial@b\eq@trial@d
 869     \csname eq@try@layout@\eq@layout\endcsname
 870   \fi
 871   \edef\eq@linewidths{\iffalse}\fi
 872 }
 873 \def\eq@frame@adjust#1{%
 874   %\addtolength#1{-2\eq@framewd-2\eq@framesep}%
 875   \dim@a\eq@framewd \advance\dim@a\eq@framesep
 876   \advance#1-2\dim@a
 877 }
 878 \def\eq@trial@succeed{%
 879   \aftergroup\@gobbletwo % cancel the \EQ@fallback code; see \eq@trial@c (?)
 880   \global\EQ@continue{\eq@trial@done}%
 881 }
 882 \def\eq@trial@done{%
 883   \let\eq@failout\relax
 884 }
 885 \def\eq@trial@init{\global\let\EQ@fallback\eq@nextlayout}
 886 \def\eq@nextlayout#1{%
 887   \endgroup
 888   \begingroup #1%
 889 }
 890 \def\eq@failout{%
 891   \global\let\EQ@trial\EQ@last@trial
 892 }
 893 \def\eq@trial@save#1{%
 894   \xdef#1{%
 895     \eq@linewidth\the\eq@linewidth
 896     % save info about the fit
 897     \eq@lines\the\eq@lines \eq@badness\the\eq@badness \def\@nx\eq@badline{\eq@badline}%
 898     % save size info
 899     \eq@wdT\the\eq@wdT \eq@wdMin\the\eq@wdMin
 900     \eq@vspan\the\eq@vspan \eq@dp\the\eq@dp \eq@firstht\the\eq@firstht
 901     % save info about the LHS
 902     \eq@wdL\the\eq@wdL \def\@nx\EQ@hasLHS{\EQ@hasLHS}%
 903     % save info about the numbering
 904     \def\@nx\eq@hasNumber{\eq@hasNumber}%
 905     % save info about the chosen layout
 906     \def\@nx\eq@layout{\eq@layout}%
 907     \def\@nx\eq@parshape{\@parshape}%
 908     \def\@nx\eq@measurements{\eq@measurements}%
 909     \def\@nx\adjust@rel@penalty{\adjust@rel@penalty}%
 910     \def\@nx\eq@shiftnumber{\eq@shiftnumber}%
 911     \def\@nx\eq@isIntertext{\@False}%
 912   }%
 913 }
 914 \def\eq@trial@b{\eq@trial@c}
 915 \def\eq@trial@c#1#2{%
 916   \begingroup
 917   \eq@trial@init
 918   \def\eq@layout{#1}%
 919   \setbox\z@\vbox{%
 920     \hfuzz\maxdimen
 921     \eq@trial@p % run the given parshape
 922     \if\@Not{\eq@badline}%
 923       \eq@trial@save\EQ@trial
 924       \if\eq@hasNumber\eq@retry@with@number\fi
 925       \if L\eq@layout \eq@check@density
 926       \else
 927         \if\@Not{\eq@badline}%
 928            \eq@trial@succeed
 929         \fi
 930       \fi
 931     \else
 932       \eq@trial@save\EQ@last@trial
 933     \fi
 934   }%
 935   \EQ@fallback{#2}%
 936   \endgroup
 937 }
 938 \def\eq@trial@d#1#2{\eq@trial@c{#1}{}}
 939 \def\eq@check@density{%
 940   \if\@Or{\@Not\EQ@hasLHS}{\eq@shortLHS}%
 941     \eq@trial@succeed
 942   \else\if\eq@dense@enough
 943     \eq@trial@succeed
 944   \fi\fi
 945 }
 946 \def\eq@shortLHS{\ifdim\eq@wdL>.44\eq@wdT 1\else 0\fi 0}
 947 \def\eq@trial@p{%
 948   \@parshape %
 949   \eq@dump@box\unhcopy\EQ@copy
 950   {\@@par}% leave \parshape readable
 951   \eq@lines\prevgraf
 952   \eq@fix@lastline
 953   \let\eq@badline\@False
 954   \if i\eq@layout \ifnum\eq@lines>\@ne \let\eq@badline\@True \fi\fi
 955   \eq@curline\eq@lines % loop counter for eq@measure@lines
 956   \let\eq@measurements\@empty
 957   \eq@ml@record@indents
 958   \eq@measure@lines
 959   \eq@recalc
 960 }
 961 \let\adjust@rel@penalty\@empty
 962 \def\eq@fix@lastline{%
 963   \setbox\tw@\lastbox \dim@b\wd\tw@
 964   \eq@dp\dp\tw@
 965   \nointerlineskip\hbox to\dim@b{\unhbox\tw@
 966     \skip@c\lastskip \unskip\unskip\hskip\skip@c
 967   }%
 968 }
 969 \def\eq@recalc{%
 970   \eq@wdT\z@ \eq@wdMin\maxdimen \eq@vspan\z@skip \eq@badness\z@
 971   \let\@elt\eq@recalc@a \eq@measurements \let\@elt\relax
 972 }
 973 \def\eq@recalc@a#1x#2+#3\@endelt{%
 974   \eq@firstht#2\relax
 975   \let\@elt\eq@recalc@b
 976   \@elt#1x#2+#3\@endelt
 977 }
 978 \def\eq@recalc@b#1X#2,#3x#4+#5@#6\@endelt{%
 979   \setlength\dim@a{#2+#3}%
 980   \ifdim\dim@a>\eq@wdT \eq@wdT\dim@a \fi
 981   \ifdim\dim@a<\eq@wdMin \eq@wdMin\dim@a \fi
 982   \eq@dp#5\relax
 983   \addtolength\eq@vspan{#1+#4+\eq@dp}%
 984   \ifnum#6>\eq@badness \eq@badness#6\relax\fi
 985 }
 986 \def\eq@layout{?}
 987 \@namedef{eq@try@layout@?}{%
 988   \let\eq@trial@b\eq@trial@c
 989   \edef\@parshape{\parshape 1 0pt \the\eq@linewidth\relax}%
 990   \setlength\dim@a{\wd\EQ@copy-2em}% Fudge; can't shrink more than this?
 991   % if we're in a numbered group, try hard to fit within the numbers
 992   \dim@b\eq@linewidth
 993   \if\eq@shiftnumber\else\if\eq@group
 994     \if\eq@hasNumber\addtolength\dim@b{-\wd\EQ@numbox-\eqnumsep}%
 995     \else\if\grp@hasNumber\addtolength\dim@b{-\wd\GRP@numbox-\eqnumsep}%
 996   \fi\fi\fi\fi
 997   \ifdim\dim@a<\dim@b% Do we even have a chance of fitting to one line?
 998     \setlength\dim@b{\columnwidth-\dim@a+\eq@wdCond}%
 999     \rightskip\z@\@plus\dim@b\@minus\hfuzz
1000     \eq@trial@b{i}{\eq@try@layout@multi}%
1001   \else
1002    \eq@try@layout@multi
1003   \fi
1004 }
1005 \def\eq@try@layout@multi{%
1006   \if\EQ@hasLHS
1007     \ifdim\eq@wdL>\eq@linewidth
1008        \setlength\dim@a{\wd\EQ@copy-\eq@wdL}%
1009        \ifdim\dim@a<.25\eq@linewidth \eq@try@layout@S
1010        \else \eq@try@layout@l
1011        \fi
1012     % BRM: Originally .7: Extreme for L since rhs has to wrap within the remaining 30+%!
1013     \else\ifdim\eq@wdL>.50\eq@linewidth
1014       \eq@try@layout@D
1015     \else
1016       \eq@try@layout@L
1017     \fi\fi
1018   \else
1019     \eq@try@layout@S % (already checked case i)
1020   \fi
1021 }
1022 \def\eq@try@layout@D{%
1023   \setlength\dim@a{\eq@linewidth -\eq@indentstep}%
1024   \edef\@parshape{\parshape 2
1025     0pt \the\eq@wdL\space \the\eq@indentstep\space \the\dim@a\relax
1026   }%
1027   \def\adjust@rel@penalty{\penalty-99 }%
1028   \eq@trial@b{D}{\eq@try@layout@A}%
1029 }
1030 \def\eq@try@layout@L{%
1031   \setlength\dim@b{\eq@linewidth-\eq@wdL}%
1032   \edef\@parshape{\parshape 2 0pt \the\eq@linewidth\space
1033     \the\eq@wdL\space \the\dim@b\relax
1034   }%
1035   \eq@trial@b{L}{\eq@try@layout@D}%
1036 }
1037 \def\eq@try@layout@S{%
1038   \setlength\dim@b{\eq@linewidth-2\eqmargin}% \advance\dim@b-1em%
1039   \int@a\wd\EQ@copy \divide\int@a\dim@b
1040   \addtolength\dim@b{-\int@a\eq@indentstep}%
1041   \if\eq@hasNumber
1042     \ifdim\dim@b>15em%
1043       \addtolength\dim@b{-\eq@wdNum}%
1044     \fi
1045   \fi
1046   \int@b\z@
1047   \def\@tempa{\dim}%
1048   \edef\@parshape{\parshape 2 0pt \the\dim@b\space
1049     \the\eqmargin\space\the\dim@b\relax}%
1050   \eq@trial@b{S}{\eq@try@layout@A}%
1051 }
1052 \def\eq@try@layout@l{%
1053   \setlength\dim@a{\eq@linewidth -\eq@indentstep}%
1054   \int@a\eq@wdL \divide\int@a\dim@a
1055   \advance\int@a\tw@
1056   \edef\@parshape{\parshape \number\int@a\space
1057     0pt \the\eq@linewidth
1058   }%
1059   \advance\int@a-\tw@
1060   \setlength\dim@b{2\eq@indentstep}%
1061   \setlength\dim@c{\eq@linewidth -\dim@b}%
1062   \edef\@parshape{\@parshape
1063     \replicate{\int@a}{\space\the\eq@indentstep\space\the\dim@a}%
1064     \space\the\dim@b\space\the\dim@c\relax
1065   }%
1066   \eq@trial@b{l}{\eq@try@layout@A}%
1067 }
1068 \def\eq@try@layout@A{%
1069   \edef\@parshape{\parshape 1 0pt \the\eq@linewidth\relax}%
1070   \if\EQ@hasLHS \def\adjust@rel@penalty{\penalty-99 }\fi
1071   \eq@trial@b{A}{}%
1072 }
1073 \let\eq@shiftnumber\@False
1074 \def\eq@retry@with@number{%
1075  \if\eq@shiftnumber
1076  \else
1077     \ifdim\eq@wdCond>\z@\if R\eqnumside
1078       \let\eq@shiftnumber\@True
1079     \fi\fi
1080     \dim@b\eq@wdNum
1081     \if L\eqnumside
1082       \ifdim\@totalleftmargin>\dim@b\dim@b\@totalleftmargin\fi
1083     \else
1084       \addtolength\dim@b{\@totalleftmargin}%
1085     \fi
1086     \setlength\dim@a{\eq@linewidth-\dim@b}%\advance\dim@a1em\relax% Allowance for shrink?
1087     \int@a\@ne\if\eq@group\int@a\maxint\fi
1088     \if\eq@shiftnumber               % Already know we need to shift
1089     \else\ifdim\eq@wdT<\dim@a % Fits!
1090     \else
1091       \setlength\leftskip{\eq@wdNum}%
1092       \setlength\rightskip{\z@\@plus\dim@a}%
1093       \adjust@parshape\@parshape
1094       \nointerlineskip
1095       \edef\eq@prev@lines{\the\eq@lines}%
1096       \edef\eq@prev@badness{\the\eq@badness}% BRM
1097       \eq@trial@p
1098       \int@a\eq@prev@badness\relax\advance\int@a 50\relax%?
1099       \int@b\eq@prev@lines  \if\eq@group\advance\int@b\@ne\fi% Allow 1 extra line in group
1100       \ifnum\eq@lines>\int@b % \eq@prev@lines
1101         \let\eq@shiftnumber\@True
1102       \else\if\eq@badline
1103         \let\eq@shiftnumber\@True
1104       \else\ifnum\eq@badness>\int@a % BRM: New case
1105         \let\eq@shiftnumber\@True
1106       \else
1107       \fi\fi%\fi
1108    \fi\fi\fi
1109    \if\eq@shiftnumber
1110      \EQ@trial% Restore parshape & other params,
1111      \leftskip\z@\let\eq@shiftnumber\@True % But set shift & leftskip
1112      \edef\@parshape{\eq@parshape}% And copy saved parshape back to `working copy' !?!?
1113    \fi
1114    \eq@trial@save\EQ@trial      % Either way, save the trial state.
1115  \fi
1116 }
1117 \def\adjust@parshape#1{%
1118   \@xp\adjust@parshape@a#1\relax
1119   \edef#1{\temp@a}%
1120 }
1121 \def\adjust@parshape@a#1 #2\relax{%
1122   \setlength\dim@a{\leftskip+\rightskip}%
1123   \edef\temp@a{#1}%
1124   \adjust@parshape@b#2 @ @ \relax
1125 }
1126 \def\adjust@parshape@b#1 #2 {%
1127   \ifx @#1\edef\temp@a{\temp@a\relax}%
1128     \@xp\@gobble
1129   \else
1130     \dim@b#1\relax
1131     \dim@c#2\relax
1132     \addtolength\dim@c{\dim@a+\dim@b}%
1133     \ifdim\dim@c>\eq@linewidth\setlength\dim@c{\eq@linewidth}\fi
1134      \addtolength\dim@c{-\dim@b}%
1135     \edef\temp@a{\temp@a\space\the\dim@b\space\the\dim@c}%
1136   \fi
1137   \adjust@parshape@b
1138 }
1139 \def\eq@ml@record@indents{%
1140   \int@a\z@
1141   \def\@tempa{%
1142     \advance\int@a\@ne
1143     \@xp\edef\csname eq@i\number\int@a\endcsname{\the\dim@a}%
1144     \ifnum\int@a<\int@b \afterassignment\@tempb \fi
1145     \dim@a
1146   }%
1147   \def\@tempb{\afterassignment\@tempa \dim@a}%
1148   \def\@tempc##1##2 {\int@b##2\afterassignment\@tempa\dim@a}%
1149   \@xp\@tempc\@parshape
1150 }
1151 \chardef\@endelt=`\?
1152 \def\eq@measurements{%
1153   \@elt 4.5pt/5.0pt,66.0ptx6.8pt+2.4pt@27\@endelt
1154   ...
1155 }
1156 \def\eq@measure@lines{%
1157   \let\eq@ml@continue\eq@measure@lines
1158   \setbox\tw@\lastbox \dim@b\wd\tw@ % find target width of line
1159   \setbox\z@\hbox to\dim@b{\unhbox\tw@}% check for overfull
1160   \eq@badness\badness
1161   \ifnum\eq@badness<\inf@bad \else \let\eq@badline\@True \fi
1162   \eq@ml@a \eq@ml@continue
1163 }
1164 \def\eq@ml@a{%
1165   \setbox\tw@\hbox{\unhbox\z@ \unskip}% find natural width
1166   \ifdim\dim@b<\wd\tw@ \setlength\dim@a{\dim@b}% shrunken line
1167   \else                \setlength\dim@a{\wd\tw@}% OK to use natural width
1168   \fi
1169   \addtolength\dim@a{-\leftskip}% BRM: Deduct the skip if we're retrying w/number
1170   \skip@a\lastskip \unskip \unpenalty
1171   \ifdim\skip@a=\z@
1172     \let\eq@ml@continue\relax % end the recursion
1173   \else
1174     % Sum repeated vskips if present
1175     \def\@tempa{%
1176       \ifdim \lastskip=\z@
1177       \else \addtolength\skip@a{\lastskip}\unskip\unpenalty \@xp\@tempa
1178       \fi
1179     }%
1180   \fi
1181   \edef\eq@measurements{\@elt
1182     \the\skip@a\space X% extra space to facilitate extracting only the
1183                         % dimen part later
1184     \csname eq@i%
1185       \ifnum\eq@curline<\parshape \number\eq@curline
1186       \else\number\parshape
1187       \fi
1188     \endcsname,\the\dim@a x\the\ht\tw@+\the\dp\tw@ @\the\eq@badness\@endelt
1189     \eq@measurements
1190   }%
1191   \advance\eq@curline\m@ne
1192   \ifnum\eq@curline=\z@ \let\eq@ml@continue\relax\fi
1193 }
1194 \def\eq@ml@vspace{%
1195   \global\advance\eq@vspan\lastskip \unskip\unpenalty
1196   \ifdim\lastskip=\z@ \else \@xp\eq@ml@vspace \fi
1197 }
1198 \def\eq@dense@enough{%
1199   \ifnum\eq@lines<\thr@@
1200     \@True
1201   \else
1202     \ifdim\eq@wdL >.7\eq@wdT
1203       \@False
1204     \else \@xp\@xp\@xp\eq@dense@enough@a
1205     \fi
1206   \fi
1207 }
1208 \def\true@false@true{\fi\fi\iftrue\iffalse\iftrue}
1209 \def\false@false@false{\fi\fi\iffalse\iffalse\iffalse}
1210 \def\false@true@false{\fi\fi\iffalse\iftrue\iffalse}
1211 \def\eq@density@factor{.475}
1212 \def\eq@dense@enough@a{%
1213   \@True \fi
1214   \ifnum\eq@lines>\sixt@@n
1215     \eq@dense@enough@b
1216   \else
1217     \dim@b\z@ \let\@elt\eq@delt \eq@measurements
1218     \dim@c\eq@density@factor\eq@wdT \multiply\dim@c\eq@lines
1219     \ifdim\dim@b>\dim@c \true@false@true \else \false@false@false \fi
1220   \fi
1221 }
1222 \def\eq@delt#1X#2,#3x#4+#5@#6\@endelt{\addtolength\dim@b{#3}}%
1223 \def\eq@dense@enough@b{%
1224   \int@b\eq@wdT \divide\int@b\p@
1225   \dim@b\eq@wdL \divide\dim@b\int@b
1226   \dim@c\eq@lines\p@ \multiply\dim@c\f@ur
1227   \int@b\eq@lines \multiply\int@b 9 \advance\int@b -10%
1228   \divide\dim@c\int@b
1229   \ifdim\dim@b<\dim@c \true@true@true \else \false@true@false \fi
1230 }
1231 \let\eq@parshape\@empty
1232 \def\eq@params{%
1233   \baselineskip\eqlinespacing
1234   \lineskip\eqlineskip \lineskiplimit\eqlineskiplimit
1235   \clubpenalty\@M \widowpenalty\@M \interlinepenalty\eqinterlinepenalty
1236   \linepenalty199 \exhyphenpenalty5000 % was 9999: make breaks at, eg. \* a bit easier.
1237   \ifdim\hfuzz<\p@ \hfuzz\p@ \fi
1238   \parfillskip\z@skip
1239   \tolerance9999 \pretolerance\m@ne
1240 }
1241 \def\eq@dump@box#1#2{%
1242   \noindent #1#2\setbox\f@ur\lastbox \setbox\tw@\lastbox
1243   \if L\eq@layout \box\tw@ \else\unhbox\tw@\fi
1244   \adjust@rel@penalty \unhbox\f@ur
1245 }
1246 \def\eq@typeset@Unnumbered{%
1247   \eq@typeset@frame
1248   \eq@typeset@equation
1249 }
1250 \def\eq@typeset@LM{%
1251   \setlength\dim@a{(\eq@vspan+\ht\EQ@numbox-\dp\EQ@numbox)/2}%
1252   \eq@typeset@leftnumber
1253   \eq@typeset@frame
1254   \eq@typeset@equation
1255 }
1256 \def\eq@typeset@LT{%
1257   \dim@a\eq@firstht
1258   \eq@typeset@leftnumber
1259   \eq@typeset@frame
1260   \eq@typeset@equation
1261 }
1262 \def\eq@typeset@LShifted{%
1263   % place number
1264   \copy\EQ@numbox \penalty\@M
1265   \dim@a\eqlineskip
1266   \if F\eq@frame\else
1267      \setlength\dim@a{\eq@framesep+\eq@framewd}%
1268   \fi
1269   \kern\dim@a
1270   \eq@typeset@frame
1271   \eq@typeset@equation
1272 }
1273 \def\eq@typeset@RM{%
1274   \setlength\dim@a{(\eq@vspan+\ht\EQ@numbox-\dp\EQ@numbox)/2}%
1275   \eq@typeset@rightnumber
1276   \eq@typeset@frame
1277   \eq@typeset@equation
1278 }
1279 \def\eq@typeset@RB{%
1280   % NOTE: is \eq@dp useful here
1281   \setlength\dim@a{\eq@vspan-\ht\EQ@numbox-\dp\EQ@numbox}%
1282   \eq@typeset@rightnumber
1283   \eq@typeset@frame
1284   \eq@typeset@equation
1285 }
1286 \def\eq@typeset@RShifted{%
1287   % place number
1288   \eq@typeset@frame
1289   \eq@typeset@equation
1290   \penalty\@M
1291   \dim@a\eqlineskip
1292   \if F\eq@frame\else
1293     \addtolength\dim@a{\eq@framesep+\eq@framewd}%
1294   \fi
1295   \parskip\dim@a
1296   \hbox to\hsize{\hfil\copy\EQ@numbox}\@@par%
1297 }
1298 \def\eq@C@setsides{%
1299   % \dim@c = space for number, if any, and not shifted.
1300   \dim@c\z@
1301   \if\eq@hasNumber\if\eq@shiftnumber\else
1302     \dim@c\eq@wdNum
1303   \fi\fi
1304   % \dim@e = space for condition(on right), if any and formula is only a single line.(to center nicely)
1305   % but only count it as being right-aligned if we're not framing, since the frame must enclose it.
1306   \dim@e\z@
1307   \if F\eq@frame
1308     \ifnum\eq@lines=\@ne\ifdim\eq@wdCond>\z@
1309       \setlength\dim@e{\eq@wdCond+\conditionsep}%
1310   \fi\fi\fi
1311   % \dim@b = minimum needed on left max(totalleftmargin, left number space)
1312   \dim@b\z@
1313   \if L\eqnumside\ifdim\dim@b<\dim@c
1314     \dim@b\dim@c
1315   \fi\fi
1316   \ifdim\dim@b<\@totalleftmargin
1317     \dim@b\z@
1318   \else
1319     \addtolength\dim@b{-\@totalleftmargin}%
1320   \fi
1321   % \dim@d = minimum needed on right max(condition, right number space)
1322   \dim@d\dim@e
1323   \if R\eqnumside\ifdim\dim@d<\dim@c
1324     \dim@d\dim@c
1325   \fi\fi
1326   % \dim@a = left margin; initially half available space
1327   % \dim@c = right margin;  ditto
1328   \setlength\dim@a{(\eq@linewidth-\eq@wdT+\dim@e+\@totalleftmargin)/2}%
1329   \dim@c=\dim@a
1330   % If too far to the left
1331   \ifdim\dim@a<\dim@b
1332      \addtolength\dim@c{\dim@a-\dim@b}%
1333      \ifdim\dim@c<\z@\dim@c=\z@\fi
1334      \dim@a=\dim@b
1335   % Or if too far to the right
1336   \else\ifdim\dim@c<\dim@d
1337      \addtolength\dim@a{\dim@c-\dim@d}%
1338      \ifdim\dim@a<\z@\dim@a=\z@\fi
1339      \dim@c=\dim@d
1340   \fi\fi
1341   % Now, \dim@d,\dim@e is the left & right glue to center each line for centerlines
1342   \setlength\dim@e{\eq@wdT-\eq@wdMin}\dim@d=\z@
1343   \dim@d\z@
1344   \if\eq@centerlines
1345     \divide\dim@e2\relax
1346     \dim@d=\dim@e
1347   \fi
1348   \setlength\leftskip{\dim@a\@plus\dim@d}%
1349   \addtolength\dim@e{\dim@c}%
1350   \setlength\rightskip{\z@\@plus\dim@e}%\@minus5\p@
1351   % Special case: if framing, reduce the stretchiness of the formula (eg. condition)
1352   % Or if we have a right number, FORCE space for it
1353   \dim@b\z@
1354   \if F\eq@frame\else
1355     \dim@b\dim@c
1356   \fi
1357   \if\@And{\eq@hasNumber}{\@Not{\eq@shiftnumber}}%
1358     \if R\eqnumside
1359       \dim@c\eq@wdNum
1360       \ifdim\dim@c>\dim@b
1361         \dim@b\dim@c
1362       \fi
1363     \fi
1364   \fi
1365   % If either of those cases requires hard rightskip, move that part from glue.
1366   \ifdim\dim@b>\z@
1367     \addtolength\dim@e{-\dim@c}%
1368     \rightskip\dim@b\@plus\dim@e%\@minus5\p@
1369   \fi
1370   % And peculiar further special case: in indented environs, width isn't where it would seem
1371   \ifdim\eq@wdCond>\z@
1372     \addtolength\rightskip{-\@totalleftmargin}%
1373   \fi
1374   \parfillskip\z@skip
1375 }
1376 \def\eq@I@setsides{%
1377   \leftskip\mathindent
1378   \if\eq@shiftnumber
1379     \setlength\dim@a{\eq@linewidth-\eq@wdT-\mathindent}%
1380     \ifdim\dim@a<\z@
1381       \leftskip=\z@ % Or something minimal?
1382     \fi
1383   \fi
1384   \dim@a=\z@
1385   \setlength\dim@b{\eq@linewidth-\leftskip-\eq@wdMin}%
1386   \if F\eq@frame
1387   \else
1388     \setlength\dim@a{\eq@linewidth-\leftskip-\eq@wdT}
1389     \addtolength\dim@b{-\dim@a}%
1390   \fi
1391   % Or force the space for right number, if needed
1392   \if\@And{\eq@hasNumber}{\@Not{\eq@shiftnumber}}%
1393     \if R\eqnumside
1394       \dim@c=\eq@wdNum
1395       \if\dim@c>\dim@a
1396         \addtolength\dim@b{-\dim@c}%
1397         \dim@a=\dim@c
1398       \fi
1399     \fi
1400   \fi
1401   \setlength\rightskip{\dim@a\@plus\dim@b \@minus\hfuzz }%\hfuzz\z@
1402   \parfillskip\z@skip
1403 }
1404 \def\eq@typeset@leftnumber{%
1405   \setlength\skip@c{\dim@a-\ht\EQ@numbox}%
1406   \vglue\skip@c% NON discardable
1407   \copy\EQ@numbox \penalty\@M
1408   \kern-\dim@a
1409 }
1410 \def\eq@typeset@rightnumber{%
1411   \setlength\skip@c{\dim@a-\ht\EQ@numbox}%
1412   \vglue\skip@c% NON discardable
1413   \hbox to \hsize{\hfil\copy\EQ@numbox}\penalty\@M
1414   \kern-\dim@a
1415 }
1416 \def\eq@typeset@equation{%
1417   \nobreak
1418   \eq@params\eq@parshape
1419   \nointerlineskip\noindent
1420   \add@grp@label
1421   \eq@dump@box\unhbox\EQ@box\@@par
1422 }
1423 \newcommand\eqframe[2]{%
1424   \begingroup
1425   \fboxrule=\eq@framewd\relax\fboxsep=\eq@framesep\relax
1426   \framebox{\z@rule\@height#2\kern#1}%
1427   \endgroup
1428 }
1429 \def\eq@addframe{%
1430   \hbox to\z@{%
1431     \setlength\dim@a{\eq@framesep+\eq@framewd}%
1432     \kern-\dim@a
1433     \vbox to\z@{\kern-\dim@a
1434       \hbox{\eqframe{\eq@wdT}{\eq@vspan}}%
1435       \vss
1436     }%
1437     \hss
1438   }%
1439 }
1440 \def\eq@typeset@frame{%
1441   \if F\eq@frame\else
1442    % Tricky: put before \noindent, so it's not affected by glue in \leftskip
1443    \nobreak\nointerlineskip
1444    \vbox to\eq@firstht{\moveright\leftskip\hbox to\z@{\eq@addframe\hss}\vss}%
1445    \kern-\eq@firstht
1446   \fi
1447 }
1448 \@saveprimitive\left\@@left
1449 \@saveprimitive\right\@@right
1450 \newcount\lr@level
1451 \def\eq@left{%
1452   \@ifnext .{\eq@nullleft}{\begingroup \let\delimiter\eq@left@a}%
1453 }
1454 \def\eq@right{%
1455   \@ifnext .{\eq@nullright}{\begingroup \let\delimiter\eq@right@a}%
1456 }
1457 \def\eq@left@a#1 #2{\endgroup\@@left\delimiter#1 \after@open}
1458 \def\eq@right@a#1 #2{\endgroup
1459   \@@right\delimiter#1 \after@close \ss@scan{#1}%
1460 }
1461 \def\eq@nullleft#1{\@@left#1\after@open}
1462 \def\eq@nullright#1{\@@right#1\after@close}
1463   % For paren matching: )
1464 \def\delim@reset{%
1465   \let\after@open\relax \let\after@close\relax
1466   \let\left\@@left \let\right\@@right
1467 }
1468 \@ifundefined{bBigg@}{% not defined
1469   \let\big@size\p@
1470   \def\big{\bBigg@{8.5}}\def\Big{\bBigg@{11.5}}%
1471   \def\bigg{\bBigg@{14.5}}\def\Bigg{\bBigg@{17.5}}%
1472   \def\biggg{\bBigg@{20.5}}\def\Biggg{\bBigg@{23.5}}%
1473 }{}
1474 \def\bBigg@#1#2{%
1475   {\delim@reset
1476    \left#2%
1477    \vrule\@height#1\big@size\@width-\nulldelimiterspace
1478    \right.
1479   }%
1480 }
1481 \def\bigl#1{\mathopen\big{#1}\after@open}
1482 \def\Bigl#1{\mathopen\Big{#1}\after@open}
1483 \def\biggl#1{\mathopen\bigg{#1}\after@open}
1484 \def\Biggl#1{\mathopen\Bigg{#1}\after@open}
1485 \def\bigggl#1{\mathopen\biggg{#1}\after@open}
1486 \def\Bigggl#1{\mathopen\Biggg{#1}\after@open}
1487
1488 \def\bigr#1{\mathclose\big{#1}\after@close}
1489 \def\Bigr#1{\mathclose\Big{#1}\after@close}
1490 \def\biggr#1{\mathclose\bigg{#1}\after@close}
1491 \def\Biggr#1{\mathclose\Bigg{#1}\after@close}
1492 \def\bigggr#1{\mathclose\biggg{#1}\after@close}
1493 \def\Bigggr#1{\mathclose\Biggg{#1}\after@close}
1494
1495 %% No change needed, I think. [mjd,1998/12/04]
1496 %%\def\bigm{\mathrel\big}
1497 %%\def\Bigm{\mathrel\Big}
1498 %%\def\biggm{\mathrel\bigg}
1499 %%\def\Biggm{\mathrel\Bigg}
1500 %%\def\bigggm{\mathrel\biggg}
1501 %%\def\Bigggm{\mathrel\Biggg}
1502 \let\m@@DeL\m@DeL \let\m@@DeR\m@DeR \let\m@@DeB\m@DeB
1503 \def\d@@DeL#1#2#3{%
1504   \delimiter"4\@xp\delim@a\csname sd@#1#2#3\endcsname #1#2#3 \after@open
1505 }
1506 \def\d@@DeR#1#2#3{%
1507   \delimiter"5\@xp\delim@a\csname sd@#1#2#3\endcsname #1#2#3 \after@close
1508 }
1509 \def\d@@DeB#1#2#3{%
1510   \delimiter"0\@xp\delim@a\csname sd@#1#2#3\endcsname #1#2#3 \after@bidir
1511 }
1512 %%BRM: These weren't defined, but apparently should be.
1513 \let\m@@DeA\m@DeA\let\d@@DeA\m@DeA%
1514 \let\after@bidir\@empty
1515 \mathchardef\zero@bop=888 \relax
1516 \mathchardef\bop@incr=4444 \relax
1517 \def\after@open{%
1518   \global\advance\lr@level\@ne
1519   \prebinoppenalty\bop@incr \multiply\prebinoppenalty\lr@level
1520   \advance\prebinoppenalty\zero@bop
1521   \ifnum\eqbreakdepth<\lr@level
1522     \let\m@Bin\m@@Bin
1523   \else
1524     \eq@binoffset=\eqbinoffset
1525     \advance\eq@binoffset\lr@level\eqdelimoffset plus1fill\relax
1526     \def\dt@fill@cancel{\hskip\z@ minus1fill\relax}%
1527   \fi
1528   \penalty\@M % BRM: discourage break after an open fence?
1529 }
1530 \def\after@close{%
1531   \global\advance\lr@level\m@ne
1532   \prebinoppenalty\bop@incr \multiply\prebinoppenalty\lr@level
1533   \advance\prebinoppenalty\zero@bop
1534   \ifnum\eqbreakdepth<\lr@level
1535   \else \let\m@Bin\d@@Bin
1536   \fi
1537   \ifnum\lr@level<\@ne \eq@binoffset=\eqbinoffset\relax \fi
1538 }
1539 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1540 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1541 \let\subsup@flag=\count@
1542 \def\ss@delim@a#1#2#3#4{\xdef\right@delim@code{\number"#2#3#4}}
1543 \def\ss@scan#1{%
1544   \begingroup
1545     \let\delim@a\ss@delim@a \@tempcnta#1\relax
1546   \endgroup
1547   \subsup@flag\@M \afterassignment\ss@scan@a \let\@let@token=}
1548 \def\ss@scan@a{%
1549   \ifx\@let@token\sb \advance\subsup@flag\@ne\else
1550   \ifx\@let@token\sp \advance\subsup@flag\tw@\else
1551     \ss@finish
1552     \expandafter\@firstoftwo % gobble \ss@scan@b
1553   \fi\fi
1554   \ss@scan@b\@let@token
1555 }
1556 \def\ss@scan@b#1#2{#1{%
1557   \let\m@Bin\m@@Bin  \let\m@Rel\m@@Rel
1558   #2}\afterassignment\ss@scan@a \let\@let@token=}%
1559 \def\ss@finish{%
1560   \@@vadjust{\penalty\thr@@}%
1561   \penalty\right@delim@code \penalty-\subsup@flag \keep@glue
1562 }
1563 \def\eq@lrunpack{\setbox\z@\lastbox
1564   \unskip \nointerlineskip
1565   \noindent\unhbox\z@ \unskip
1566   \subsup@flag-\lastpenalty \unpenalty
1567   \xdef\right@delim@code{\number\lastpenalty}%
1568   \unpenalty
1569   \ifnum\subsup@flag>\@M
1570     \advance\subsup@flag-\@M
1571     \setbox\tw@\lastbox
1572   \else \setbox\tw@\box\voidb@x
1573   \fi
1574   \setbox\z@\lastbox
1575   \ifvoid\tw@ \unhbox\z@
1576   \else \lrss@reattach % uses \subsup@flag, box\z@, box\tw@
1577   \fi
1578   \penalty-\@Mi\z@rule\@@par
1579   \setbox\z@\lastbox \unskip\unpenalty
1580 %%{\showboxbreadth\maxdimen\showboxdepth99\showlists}%
1581 }
1582 \dimendef\sub@depth=8 \dimendef\sup@base=6
1583 \dimendef\prelim@sub@depth=4 \dimendef\prelim@sup@base=2
1584 \def\sym@xheight{\fontdimen5\textfont\tw@}
1585 \def\sup@base@one{\fontdimen13\textfont\tw@}
1586 \def\sub@base@one{\fontdimen16\textfont\tw@}
1587 \def\sub@base@two{\fontdimen17\textfont\tw@}
1588 \def\sup@drop{\fontdimen18\scriptfont\tw@}
1589 \def\sub@drop{\fontdimen19\scriptfont\tw@}
1590 \providecommand{\mathaxis}{\fontdimen22\textfont\tw@}
1591 \def\lrss@reattach{%
1592   \begingroup
1593   % "The TeXbook" Appendix G step 18:
1594   \setlength\prelim@sup@base{\ht\z@-\sup@drop}%
1595   \setlength\prelim@sub@depth{\dp\z@ +\sub@drop}%
1596   \unhbox\z@
1597   \ifcase\subsup@flag      % case 0: this can't happen
1598   \or \lr@subscript   % case 1: subscript only
1599   \or \lr@superscript % case 2: superscript only
1600   \else \lr@subsup    % case 3: sub and superscript both
1601   \fi
1602   \endgroup
1603 }
1604 \def\lr@subscript{%
1605   \sub@depth\sub@base@one
1606   \ifdim\prelim@sub@depth>\sub@depth \sub@depth\prelim@sub@depth\fi
1607   \setlength\dim@a{\ht\tw@  -.8\sym@xheight}%
1608   \ifdim\dim@a>\sub@depth \sub@depth=\dim@a \fi
1609   \twang@adjust\sub@depth
1610   \lower\sub@depth\box\tw@
1611 }
1612 \def\lr@superscript{%
1613   \sup@base\sup@base@one
1614   \ifdim\prelim@sup@base>\sup@base \sup@base\prelim@sup@base\fi
1615   \setlength\dim@a{\dp\tw@ -.25\sym@xheight}%
1616   \ifdim\dim@a>\sup@base \sup@base\dim@a \fi
1617   \twang@adjust\sup@base
1618   \raise\sup@base\box\tw@
1619 }
1620 \def\lr@subsup{%
1621   \sub@depth\sub@base@two
1622   \ifdim\prelim@sub@depth>\sub@depth \sub@depth\prelim@sub@depth \fi
1623   \twang@adjust\sub@depth
1624   \lower\sub@depth\box\tw@
1625 }
1626 \def\twang@adjust#1{%
1627   \begingroup
1628     \@ifundefined{twang@\right@delim@code}{}{%
1629       \setlength\dim@d{#1-\mathaxis}%
1630       % put an upper limit on the adjustment
1631       \ifdim\dim@d>1em \dim@d 1em \fi
1632       \kern\csname twang@\right@delim@code\endcsname\dim@d
1633     }%
1634   \endgroup
1635 }
1636 \newcommand{\DeclareTwang}[2]{%
1637   \ifcat.\@nx#1\begingroup
1638     \lccode`\~=`#1\lowercase{\endgroup \DeclareTwang{~}}{#2}%
1639   \else
1640     \@xp\decl@twang#1?\@nil{#2}%
1641   \fi
1642 }
1643 \def\decl@twang#1#2#3#4#5#6#7\@nil#8{%
1644   \@namedef{twang@\number"#4#5#6}{#8}%
1645 }
1646 \DeclareTwang{\rangle}{-.4}
1647 \DeclareTwang{)}{-.33}
1648 \DeclareTwang{\rbrace}{-.25}
1649 \newenvironment{dseries}{\let\eq@hasNumber\@True \@optarg\@dseries{}}{}%
1650 \def\enddseries#1{\check@punct@or@qed}%
1651 \newenvironment{dseries*}{\let\eq@hasNumber\@False \@optarg\@dseries{}}{}%
1652 \@namedef{enddseries*}#1{\check@punct@or@qed}%
1653 \@namedef{end@dseries*}{\end@dseries}%
1654 \def\@dseries[#1]{%
1655   \let\display@setup\dseries@display@setup
1656   % Question: should this be the default for dseries???
1657   \global\eq@wdCond\z@
1658   \@dmath[layout={M},#1]%
1659   \mathsurround\z@\@@math \penalty\@Mi
1660   \let\endmath\ends@math
1661   \def\premath{%
1662     \ifdim\lastskip<.3em \unskip
1663     \else\ifnum\lastpenalty<\@M \dquad\fi\fi
1664 }%
1665   \def\postmath{\unpenalty\eq@addpunct \penalty\intermath@penalty \dquad \@ignoretrue}%
1666 \ignorespaces
1667 }
1668 \def\end@dseries{%
1669   \unskip\unpenalty
1670   \@@endmath \mathsurround\z@ \end@dmath
1671 }
1672 \def\eq@try@layout@M{%
1673   \edef\@parshape{\parshape 1 0pt \the\eq@linewidth\relax}%
1674   \eq@trial@b{M}{}%
1675 }
1676 \def\intermath@penalty{-221}%
1677 \newcommand\dquad{\hskip0.6em minus.3em}
1678 \newcommand\premath{}\newcommand\postmath{}
1679 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1680 \renewenvironment{math}{%
1681   \leavevmode \premath
1682   \ifmmode\@badmath\else\@@math\fi
1683 }{%
1684   \ifmmode\@@endmath\else\@badmath\fi
1685 }
1686 \def\ends@math#1{\check@punct@or@qed}
1687 \def\end@math{%
1688   \ifmmode\@@endmath\else\@badmath\fi
1689   \postmath
1690 }
1691 \let\eq@group\@False
1692 \let\grp@shiftnumber\@False
1693 \let\grp@hasNumber\@False
1694 \let\grp@eqs@numbered\@False
1695 \let\grp@aligned\@True
1696 \newenvironment{dgroup}{%
1697   \let\grp@hasNumber\@True\@optarg\@dgroup{}%
1698 }{%
1699   \end@dgroup
1700 }
1701 \newtoks\GRP@queue
1702 \newenvironment{dgroup*}{%
1703   \let\grp@hasNumber\@False\@optarg\@dgroup{}%
1704 }{%
1705   \end@dgroup
1706 }
1707 \def\@dgroup[#1]{%
1708   \let\eq@group\@True \global\let\eq@GRP@first@dmath\@True
1709   \global\GRP@queue\@emptytoks \global\setbox\GRP@box\box\voidb@x
1710   \global\let\GRP@label\@empty
1711   \global\grp@wdL\z@\global\grp@wdR\z@\global\grp@wdT\z@
1712   \global\grp@linewidth\z@\global\grp@wdNum\z@
1713   \global\let\grp@eqs@numbered\@False
1714   \global\let\grp@aligned\@True
1715   \global\let\grp@shiftnumber\@False
1716   \eq@prelim
1717   \setkeys{breqn}{#1}%
1718   \if\grp@hasNumber \grp@setnumber \fi
1719 }
1720 \def\end@dgroup{%
1721   \EQ@displayinfo \grp@finish
1722   \if\grp@hasNumber\grp@resetnumber\fi
1723 }
1724 \@ifundefined{c@parentequation}{\newcounter{parentequation}}{}
1725 \global\let\GRP@label\@empty
1726 \def\add@grp@label{%
1727   \ifx\@empty\GRP@label
1728   \else \GRP@label \global\let\GRP@label\@empty
1729   \fi
1730 }
1731 \def\grp@setnumber{%
1732   \global\let\GRP@label\next@label \global\let\next@label\@empty
1733   % Trick \eq@setnumber to doing our work for us.
1734   \let\eq@hasNumber\@True
1735   \eq@setnumber
1736   \global\sbox\GRP@numbox{\unhbox\EQ@numbox}%
1737   \grp@wdNum\eq@wdNum
1738   \let\eq@hasNumber\@False
1739   \let\eq@number\@empty
1740   \eq@wdNum\z@
1741   \protected@edef\theparentequation{\theequation}%
1742   \setcounter{parentequation}{\value{equation}}%
1743   \setcounter{equation}{0}%
1744   \def\theequation{\theparentequation\alph{equation}}%
1745 }
1746 \def\grp@resetnumber{%
1747   \setcounter{equation}{\value{parentequation}}%
1748 }
1749 \newbox\GRP@box
1750 \newbox\GRP@wholebox
1751 \def\grp@push{%
1752   \global\GRP@queue\@xp\@xp\@xp{\@xp\the\@xp\GRP@queue
1753     \@xp\@elt\@xp{\EQ@trial}%
1754   }%
1755   \global\setbox\GRP@box\vbox{%
1756     \hbox{\box\EQ@box\box\EQ@copy\penalty\@ne\copy\EQ@numbox}%
1757     \unvbox\GRP@box
1758   }%
1759   \EQ@trial
1760   \if\eq@isIntertext\else
1761     \ifdim\eq@wdL>\grp@wdL \global\grp@wdL\eq@wdL \fi
1762     \ifdim\eq@wdT>\grp@wdT \global\grp@wdT\eq@wdT \fi
1763     \setlength\dim@a{\eq@wdT-\eq@wdL}%
1764     \ifdim\dim@a>\grp@wdR \global\grp@wdR\dim@a \fi
1765     \ifdim\eq@linewidth>\grp@linewidth \global\grp@linewidth\eq@linewidth\fi
1766     \if\eq@hasNumber
1767        \global\let\grp@eqs@numbered\@True
1768        \ifdim\eq@wdNum>\grp@wdNum\global\grp@wdNum\eq@wdNum\fi
1769     \fi
1770     \if\EQ@hasLHS\else\global\let\grp@aligned\@False\fi
1771     \if D\eq@layout \global\let\grp@aligned\@False\fi % Layout D (usually) puts rel on 2nd line.
1772     \if\eq@shiftnumber\global\let\grp@shiftnumber\@True\fi % One eq shifted forces all.
1773   \fi
1774 }
1775 \def\grp@finish{%
1776   \setlength\dim@a{\grp@wdL+\grp@wdR-4em}% Allowance for shrink?
1777   \if\grp@aligned
1778     \ifdim\dim@a>\grp@linewidth
1779       \global\let\grp@aligned\@False
1780     \fi
1781   \fi
1782   \addtolength\dim@a{\grp@wdNum }% Effective length
1783   \if\grp@shiftnumber
1784   \else
1785     \if\@And{\grp@hasNumber}{\@Not\grp@eqs@numbered}
1786       \ifdim\dim@a>\grp@linewidth
1787         \global\let\grp@shiftnumber\@True
1788       \fi
1789     \fi
1790   \fi
1791   \if\grp@aligned
1792      \global\grp@wdT\grp@wdL
1793      \global\advance\grp@wdT\grp@wdR
1794   \fi
1795   \setbox\GRP@wholebox\vbox{%
1796     \let\@elt\eqgrp@elt
1797     \the\GRP@queue
1798   }%
1799   \global\let\eq@GRP@first@dmath\@True
1800   \begingroup
1801   \dmath@first@leftskip
1802   \eq@topspace{\vskip\parskip}%
1803   \endgroup
1804   \if\@And{\grp@hasNumber}{\@Not{\grp@eqs@numbered}}%
1805     \if\grp@shiftnumber
1806       \copy\GRP@numbox \penalty\@M
1807       \kern\eqlineskip
1808     \else
1809       \setlength\dim@a{%
1810         (\ht\GRP@wholebox+\dp\GRP@wholebox+\ht\GRP@numbox-\dp\GRP@numbox)/2}%
1811       \setlength\skip@c{\dim@a-\ht\GRP@numbox}%
1812       \vglue\skip@c% NON discardable
1813       \copy\GRP@numbox \penalty\@M
1814       \kern-\dim@a
1815       \kern-\abovedisplayskip % To cancel the topspace above the first eqn.
1816     \fi
1817   \fi
1818   \unvbox\GRP@wholebox
1819   \let\@elt\relax
1820   \eq@botspace % not needed unless bottom number?
1821 }
1822 \def\eqgrp@elt#1{%
1823   \global\setbox\GRP@box\vbox{%
1824     \unvbox\GRP@box
1825     \setbox\z@\lastbox
1826     \setbox\tw@\hbox{\unhbox\z@
1827       \ifnum\lastpenalty=\@ne
1828       \else
1829         \global\setbox\EQ@numbox\lastbox
1830       \fi
1831       \unpenalty
1832       \global\setbox\EQ@copy\lastbox
1833       \global\setbox\EQ@box\lastbox
1834     }%
1835   }%
1836   \begingroup \let\eq@botspace\relax
1837   #1%
1838   \if\eq@isIntertext
1839     \vskip\belowdisplayskip
1840     \unvbox\EQ@copy
1841   \else
1842     \grp@override
1843     \eq@finish
1844   \fi
1845   \endgroup
1846 }
1847 \def\grp@override{%
1848   \def\eqindent{I}%
1849   \setlength\dim@a{(\grp@linewidth-\grp@wdT)/2}%
1850   \ifdim\dim@a<\z@\dim@a=\z@\fi
1851   \dim@b\if L\eqnumside\grp@wdNum\else\z@\fi
1852   \if\grp@shiftnumber\else
1853     \ifdim\dim@b>\dim@a\dim@a\dim@b\fi
1854   \fi
1855   \if\grp@aligned
1856     \addtolength\dim@a{\grp@wdL-\eq@wdL}%
1857   \fi
1858   \mathindent\dim@a
1859   \ifdim\dim@b>\dim@a
1860     \let\eq@shiftnumber\@True
1861   \fi
1862 }
1863 \newskip\darraycolsep \darraycolsep 20pt plus1fil minus12pt
1864 \newcount\cur@row \newcount\cur@col
1865 \def\@tempa#1#2#3{%
1866   \cur@col#1 \hfil
1867   \setbox\z@\hbox{$\displaystyle####\m@th$}\@nx\col@box
1868   \tabskip\z@skip
1869   &\cur@col#2 \hfil
1870   \setbox\z@\hbox{$\displaystyle\mathord{}####\mathord{}\m@th$}\@nx\col@box
1871   \hfil
1872   &\cur@col#3 \setbox\z@\hbox{$\displaystyle####\m@th$}\@nx\col@box
1873   \hfil\tabskip\darraycolsep
1874 }
1875 \xdef\darray@preamble{%
1876   \@tempa 123&\@tempa 456&\@tempa 789%
1877   &\@tempa{10}{11}{12}&\@tempa{13}{14}{15}&\@tempa{16}{17}{18}%
1878   \cr
1879 }
1880 \@ifundefined{Mathstrut@}{\let\Mathstrut@\strut}{}
1881 \def\darray@cr{\Mathstrut@\cr}
1882 \def\col@box{%
1883   \unhbox\z@
1884 }
1885 \newenvironment{darray}{\@optarg\@darray{}}{}
1886 \def\@darray[#1]{%
1887   \if\eq@group\else\eq@prelim\fi
1888   \global\let\@preamble\@empty
1889   \setkeys{breqn}{#1}%
1890   \the\eqstyle \eq@setnumber
1891   \ifx\@preamble\@empty \global\let\@preamble\darray@preamble \fi
1892   \check@mathfonts
1893   % \let\check@mathfonts\relax % tempting, but too risky
1894   \@xp\let\csname\string\ \endcsname\darray@cr
1895   \setbox\z@\vbox\bgroup
1896   \everycr{\noalign{\global\advance\cur@row\@ne}}%
1897   \tabskip\z@skip \cur@col\z@
1898   \global\cur@row\z@
1899   \penalty\@ne % flag for \dar@repack
1900   \halign\@xp\bgroup\@preamble
1901 }
1902 \def\enddarray#1{\check@punct@or@qed}
1903 \def\end@darray{%
1904   \ifvmode\else \eq@addpunct \Mathstrut@\fi\crcr \egroup
1905   \dar@capture
1906   \egroup
1907 }
1908 \def\dar@capture{%
1909 %% \showboxbreadth\maxdimen\showboxdepth99\showlists
1910   \eq@wdL\z@ \eq@wdRmax\z@
1911   \dar@repack
1912 }
1913 \def\dar@repack{%
1914   \unpenalty
1915   \setbox\tw@\lastbox
1916   \global\setbox\EQ@box\hbox{%
1917     \hbox{\unhcopy\tw@\unskip}\penalty-\@M \unhbox\EQ@box}%
1918   \global\setbox\EQ@copy\hbox{%
1919     \hbox{\unhbox\tw@\unskip}\penalty-\@M \unhbox\EQ@copy}%
1920   \unskip
1921   \ifcase\lastpenalty \else\@xp\@gobble\fi
1922   \dar@repack
1923 }
1924 \newskip\conditionsep \conditionsep=10pt minus5pt%
1925 \newcommand{\conditionpunct}{,}
1926 \let\cond@gobble\@firstofone
1927 \newcommand\condition{%
1928   \begingroup\@tempswatrue
1929     \@ifstar{\@tempswafalse \condition@a}\condition@a
1930 }
1931 \newcommand\condition@a[2][\conditionpunct]{%
1932   \unpenalty\unskip\unpenalty\unskip % BRM Added
1933   \hbox{#1}%
1934   \penalty -201\relax\hbox{}% Penalty to allow breaks here.
1935   \hskip\conditionsep
1936   \if@tempswa \@xp\hbox \else \@xp\condition@b\fi
1937   {#2}%
1938   \endgroup
1939   \setbox\z@\if@tempswa\hbox{#2}\else\hbox{\textmath@setup #2}\fi
1940   \global\eq@wdCond\wd\z@
1941   \let\cond@gobble\@gobble
1942 }
1943 \newcommand\condition@b[1]{%
1944   \cond@gobble{\hskip\conditionsep}%
1945   \textmath@setup #1%
1946 }
1947 \newenvironment{XXXXdsuspend}{%
1948   \global\setbox\EQ@box\vbox\bgroup \@parboxrestore
1949     \parshape 1 \displayindent \displaywidth\relax
1950     \hsize=\columnwidth \noindent\ignorespaces
1951 }{%
1952   \par\egroup
1953   \global\setbox\GRP@box\vbox{%
1954     \vbox{\copy\EQ@box\vtop{\unvbox\EQ@box}}%
1955     \unvbox\GRP@box
1956   }%
1957   \global\GRP@queue\@xp{\the\GRP@queue
1958     \@elt{\gdef\EQ@trial{}}%
1959   }%
1960 }
1961 \newenvironment{dsuspend}{%
1962   \global\setbox\EQ@box\vbox\bgroup \@parboxrestore
1963     \parshape 1 \displayindent \displaywidth\relax
1964     \hsize=\columnwidth \noindent\ignorespaces
1965 }{%
1966   \par\egroup
1967   \global\setbox\GRP@box\vbox{%
1968     \hbox{\copy\EQ@box\vtop{\unvbox\EQ@box}}%
1969     \unvbox\GRP@box
1970   }%
1971   \global\GRP@queue\@xp{\the\GRP@queue
1972      \@elt{\let\eq@isIntertext\@True}%
1973   }%
1974 }
1975 \newcommand\breqn@intertext[1]{\dsuspend#1\enddsuspend}
1976 \renewcommand{\*}{%
1977   \if@display
1978     \setbox\z@\hbox{\mathsurround\z@$\mkern\eq@binoffset$}%
1979     \discretionary{}{%
1980       \kern\the\wd\z@ \textchar\discretionarytimes
1981     }{}%
1982     \thinspace
1983   \else
1984     \discretionary{\thinspace\textchar\discretionarytimes}{}{}%
1985   \fi
1986 }
1987 \newcommand{\discretionarytimes}{\times}
1988 \def\nref#1{\@xp\@nref\csname r@#1\endcsname}
1989 \def\@nref#1#2{\ifx\relax#1??\else \@xp\@firstoftwo#1\fi}
1990 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1991 \endinput
1992 %%
1993 %% End of file `breqn.sty'.