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|
%%% ====================================================================
%%% @LaTeX-doc-source-file{
%%% filename = "mathscinet.dtx",
%%% version = "2.01",
%%% date = "2004/06/30",
%%% time = "12:00:17 EDT",
%%% author = "Michael J Downes and David M. Jones",
%%% address = "American Mathematical Society,
%%% Publications Technical Group,
%%% PO Box 6248,
%%% Providence, RI 02940,
%%% USA",
%%% email = "tech-support@ams.org",
%%% URL = "http://www.ams.org/",
%%% abstract = "",
%%% copyright = "Copyright 2001 American Mathematical Society.",
%%% license = "Unlimited copying and redistribution of this file
%%% are permitted as long as this file is not
%%% modified. Modifications, and distribution of
%%% modified versions, are permitted, but only if
%%% the resulting file is renamed.",
%%% checksum = "34681 595 2175 20194",
%%% docstring = "The checksum field, produced by Robert Solovay's
%%% checksum utility, gives CRC-16 checksum, lines,
%%% words, and characters.",
%%% }
%%% ====================================================================
%%%
% \iffalse
%<*driver>
\NeedsTeXFormat{LaTeX2e}
\documentclass[draft]{amsdtx}
\usepackage{mathscinet}
\newcommand{\uchar}[1]{{\small \texttt{U+#1}}}
\newcommand{\enc}{\texttt}
\newenvironment{chartable}{%
\begin{tabular}{%
l@{\extracolsep{1em}}%
l@{\extracolsep{1em}}%
r@{\extracolsep{2em}}%
l@{\extracolsep{1em}}%
l@{\extracolsep{1em}}%
r}%
}{%
\end{tabular}%
}
\makeatletter
\DeclareTextCommandDefault{\xudot}{\@underaccent\@empty{'137}}
\makeatother
\MakeShortVerb{\|}
\begin{document}
\title{The \pkg{mathscinet} package}
\author{American Mathematical Society}
\date{Version \fileversion, \filedate}
\hDocInput{mathscinet.dtx}
\end{document}
%</driver>
% \fi
%
% \maketitle
% \section{Introduction}
%
% The \pkg{mathscinet} packages provides definitions for certain
% commands that occasionally occur in bibliographic data exported
% from MathSciNet and that are not provided by \latex/.
%
% \textbf{Warning:} Although the macros provided in this package
% are probably acceptable if all you need to do is format an entry
% downloaded from MathSciNet, they should probably not be used for
% other purposes. In general, if you are trying to typeset
% material in any languages that require these characters, you are
% better off using specialized fonts and encodings for those
% languages.
%
% All Unicode character references are taken from \emph{The Unicode
% Standard, Version~3.0} (Addison-Wesley, 2000).
%
% \StopEventually{}
%
% \section{Implementation}
% Standard declaration of package name and date.
% \begin{macrocode}
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{mathscinet}[2002/04/17 v1.05]
\RequirePackage{textcmds}\relax
% \end{macrocode}
%
% \begin{macro}{\setboxz@h}
% A useful abbreviation borrowed from \pkg{amsgen}.
% \begin{macrocode}
\providecommand\setboxz@h{\setbox\z@\hbox}
% \end{macrocode}
% \end{macro}
%
% \subsection{Math font commands}
%
% \begin{macro}{\bold}
% \begin{macro}{\scr}
% These are simple aliases of core \latex/ commands.
% \begin{macrocode}
\providecommand{\bold}{\mathbf}
\providecommand{\scr}{\mathcal}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\germ}
% Since this doesn't correspond to a core \latex/ command, we
% generate an error if no appropriate definition is available.
% \begin{macrocode}
\AtBeginDocument{%
\@ifundefined{mathfrak}{%
\providecommand{\germ}{%
\PackageError{mathscinet}{To use the \string\germ\space
command, please load the amsfonts package}\@ehc
}%
}{%
\providecommand{\germ}{\mathfrak}%
}%
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\romsup}
% \begin{macro}{\asup}
% The \cs{tsup} command comes from the \pkg{textcmds} package.
% \begin{macrocode}
\providecommand{\romsup}{\tsup}
\providecommand{\asup}{\tsup}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\hslash}
% Planck's constant over~$2\pi$:~$\hslash$ (\uchar{210F}).
%
% If the \pkg{amssymb} package isn't loaded, we just want this to
% be an alias for |\hbar|, which is defined in the \latex/ kernel
% (and then redefined by the \pkg{amssymb} package). If the
% \pkg{amssymb} package is loaded, we want to use its definition
% of~|\hslash|. To prevent problems if \pkg{amsrefs} is loaded
% before \pkg{amssymb}, we defer our definition of \cn{hslash}
% until after all packages have been loaded.
% \begin{macrocode}
\AtBeginDocument{\providecommand{\hslash}{\hbar}}
% \end{macrocode}
% \end{macro}
%
% \subsection{Arabic transliteration}
%
% \begin{macro}{\rasp}
% Transliteration of the Arabic letter \emph{hamza}
% (\uchar{0621}):~\rasp\ (\uchar{02BE}).
% \begin{macrocode}
\ProvideTextCommandDefault{\rasp}{\leavevmode\raise.45ex\hbox{$\rhook$}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\lasp}
% Transliteration of the Arabic letter \emph{ain}
% (\uchar{0639}):~\lasp\ (\uchar{02BF}).
% \begin{macrocode}
\ProvideTextCommandDefault{\lasp}{\leavevmode\raise.45ex\hbox{$\lhook$}}
% \end{macrocode}
% \end{macro}
%
% \subsection{Latin Extended-A (\texttt{latin1}) characters}
%
% These are based on Barbara Beeton's definitions from
% \fn{amsclass.dtx}.
%
% \begin{macro}{\Dbar}
% Latin capital letter D with stroke:~\Dbar\ (\uchar{0110}). In the
% T1 encoding, we just use |\DJ|; otherwise we fake it.
% \begin{macrocode}
\ProvideTextCommand{\Dbar}{T1}{\DJ}
\ProvideTextCommandDefault{\Dbar}{%
\leavevmode\lower.5ex\rlap{\hskip-.07em\accent"16}D%
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\dbar}
% Latin lower letter~d with stroke:~\dbar\ (\uchar{0111}). In the
% T1 encoding, we just use |\dj|; otherwise we fake it.
% \begin{macrocode}
\ProvideTextCommand{\dbar}{T1}{\dj}
% \end{macrocode}
% If it looks like this is a small-caps font, we adjust the spacing
% appropriately.
% \begin{macrocode}
\ProvideTextCommandDefault{\dbar}{%
\begingroup
\edef\@tempa{\scdefault}%
\ifx\@tempa\f@shape
\dimen@-.75ex
\dimen@i-.08em
\else
\dimen@.02ex
\dimen@i.1em
\fi
\leavevmode\raise\dimen@\rlap{\hskip\dimen@i\char"16}d%
\endgroup
}
% \end{macrocode}
% \end{macro}
%
% \subsection{Cyrillic transliteration}
%
% \begin{macro}{\cprime}
% Transliteration of the Cyrillic letter soft sign
% (\uchar{042C}):~\cprime.
% \begin{macrocode}
\ProvideTextCommandDefault{\cprime}{\tprime}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\cdprime}
% Transliteration of the Cyrillic letter hard sign
% (\uchar{042A}):~\cdprime.
% \begin{macrocode}
\ProvideTextCommandDefault{\cdprime}{\tprime\tprime}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\bud}
% Ditto.
% \begin{macrocode}
\ProvideTextCommandDefault{\bud}{\cdprime}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\cydot}
% Vertically centered dot.
% \begin{macrocode}
\ProvideTextCommandDefault{\cydot}{\leavevmode\raise.4ex\hbox{.}}
% \end{macrocode}
% \end{macro}
%
% \subsection{Miscellaneous diacritics (aka Frankenstein's\\
% diacritics)}
%
% \begin{macro}{\save@sf}
% When putting together an accented character from bits and pieces,
% the |\spacefactor| of the base character often gets lost in the
% shuffle. We use essentialy the same technique as |\add@accent|
% to save and restore the spacefactor, but we wrap in in a pair of
% macros for convenience.
% \begin{macrocode}
\def\save@sf{%
\ifmmode\else\global\mathchardef\accent@spacefactor\spacefactor\fi
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\restore@sf}
% And here's the corresponding restore.
% \begin{macrocode}
\def\restore@sf{\ifmmode\else\spacefactor\accent@spacefactor\fi}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@underaccent}
% This is perhaps the most interesting macro in this package (which
% admittedly isn't saying much). It attempts to convert a character
% (usually one of the standard above-letter diacritics like~\"{})
% into an underhanging diacritic (like~\dudot{\hbox to
% .5em{\hss}}). This is similar in spirit to the way that the
% \enc{OT1} \cn{b} command converts a macron into a bar-under
% accent, or the way that \cn{d} converts a period into an
% underhanging dot. However, the technique used here is a little
% more complicated and, hopefully, a little more general, in the
% sense of requiring fewer ad-hoc parameters. It only contains one
% magic constant (.2\,ex), which seems to provide reasonable
% results for all of the Computer Modern fonts.
%
% The basic algorithm is as follows:
%
% \begin{enumerate}
%
% \item
% Create a box~$B$ containing the base character at its natural
% height, depth, and width.
%
% \item
% Create a box~$d$ consisting of the diacritic centered in a space
% equal to the width of~$B$.
%
% \item
% Lower box~$d$ by the sum of its height (to bring the top of~$d$
% down to the baseline) plus the depth of $B$ (to bring the top
% of~$d$ down to the bottom of~$B$) plus .2\,ex (to provide the
% spacing between the bottom of the letter and the top of the
% diacritic). Call the new box~$d'$.
%
% \item
% Create a new box~$C$ by superimposing boxes $B$ and~$d'$.
%
% \item
% If the height of~$d$ was greater than 1\,ex, reset the depth of
% box~$C$ to the sum of the depth of~$B$ and 1\,ex less than the
% height of~$d$. (See the appendix for a discussion of this step.)
%
% \end{enumerate}
%
% \begin{macrocode}
\def\@underaccent#1#2#3{%
\leavevmode
\begingroup
\ifmmode\let\@mathtoggle$\else\let\@mathtoggle\relax\fi
\setboxz@h{\@mathtoggle#3\save@sf\@mathtoggle}%
\setbox\@ne\hb@xt@\wd\z@{%
\hss\fontshape\updefault\rmfamily#1\char#2\hss
}%
\dimen@\ht\@ne
\advance\dimen@\dp\z@
\advance\dimen@.2ex
\setboxz@h{\lower\dimen@\rlap{\copy\@ne}\unhbox\z@}%
\ifdim\ht\@ne>1ex
\advance\dimen@-1.2ex
\dp\z@\dimen@
\fi
\box\z@
\restore@sf
\endgroup
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\utilde}
% Tilde below (\uchar{0330}):
%
% \begin{chartable}
% |\utilde{E}| & \utilde{E} & \uchar{1E1A} &
% |\utilde{e}| & \utilde{e} & \uchar{1E1B} \\
% |\utilde{I}| & \utilde{I} & \uchar{1E2C} &
% |\utilde{i}| & \utilde{i} & \uchar{1E2D} \\
% |\utilde{U}| & \utilde{U} & \uchar{1E74} &
% |\utilde{u}| & \utilde{u} & \uchar{1E75}
% \end{chartable}
% \begin{macrocode}
\DeclareTextCommandDefault{\utilde}{\@underaccent\@empty{`\~}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\uarc}
% Breve below (\uchar{032E}):
%
% \begin{chartable}
% |\uarc{H}| & \uarc{H} & \uchar{1E2A} &
% |\uarc{h}| & \uarc{h} & \uchar{1E2B}
% \end{chartable}
% \begin{macrocode}
\DeclareTextCommandDefault{\uarc}{\@underaccent\@empty{'025}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\lfhook}
% Comma below (\uchar{0326}):
%
% \begin{chartable}
% |\lfhook{S}| & \lfhook{S} & \uchar{0218} &
% |\lfhook{s}| & \lfhook{s} & \uchar{0219} \\
% |\lfhook{T}| & \lfhook{T} & \uchar{021A} &
% |\lfhook{t}| & \lfhook{t} & \uchar{021B}
% \end{chartable}
% \begin{macrocode}
\DeclareTextCommandDefault{\lfhook}{\@underaccent\supsize{`\,}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\dudot}
% Diaeresis below (\uchar{0324}):
%
% \begin{chartable}
% |\dudot{U}| & \dudot{U} & \uchar{1E72} &
% |\dudot{u}| & \dudot{u} & \uchar{1E73}
% \end{chartable}
% \begin{macrocode}
\DeclareTextCommandDefault{\dudot}{\@underaccent\@empty{'177}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\udot}
% Dot below (\uchar{0323}): There are two options for implementing
% this: either map to the standard \cn{d} accent or define using
% \cs{@underaccent}. If we choose the former, we have two
% problems: (a)~when applied to capital letters, the standard
% \enc{T1} and \enc{OT1} implementations of~|\d| produce
% \cs{spacefactor}s of~1000 instead of~999, and (b)~the
% underspacing of the \cs{udot} accent will differ from that of the
% \cs{dudot} accent:~\udot{x}\dudot{x}. On the other hand, if we
% choose the latter, course, \cn{d} and \cn{udot} will
% differ:~\d{x}\xudot{x}.
% Neither solution appeals, but it's easier to stick with~\cs{d},
% so that's what I'll do.
% \begin{macrocode}
\DeclareTextCommandDefault{\udot}{\d}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\polhk}
% Ogonek (Polish hook) (\uchar{0328}):
%
% \begin{chartable}
% |\polhk{A}| & \polhk{A} & \uchar{0104} &
% |\polhk{a}| & \polhk{a} & \uchar{0105} \\
% |\polhk{E}| & \polhk{E} & \uchar{0118} &
% |\polhk{e}| & \polhk{e} & \uchar{0119} \\
% |\polhk{I}| & \polhk{I} & \uchar{012E} &
% |\polhk{i}| & \polhk{i} & \uchar{012F} \\
% |\polhk{U}| & \polhk{U} & \uchar{0172} &
% |\polhk{u}| & \polhk{u} & \uchar{0173} \\
% |\polhk{O}| & \polhk{O} & \uchar{01EA} &
% |\polhk{o}| & \polhk{o} & \uchar{01EB}
% \end{chartable}
%
% The \enc{T1} and \enc{OT4} encodings implement the |\k| accent,
% so we just use it for most characters, although we will
% supplement them later with
% \begin{macrocode}
\DeclareTextCommand{\polhk}{OT4}{\k}
\DeclareTextCommand{\polhk}{T1}{\k}
% \end{macrocode}
%
% \begin{macrocode}
\DeclareTextCommand{\polhk}{OT1}[1]{\TextSymbolUnavailable{\k{#1}}#1}
% \end{macrocode}
%
% \begin{macrocode}
\DeclareTextCompositeCommand{\polhk}{OT1}{a}{\msc@ogonek {.6}{.07} a}
\DeclareTextCompositeCommand{\polhk}{OT1}{A}{\msc@ogonek {.6}{.07} A}
\DeclareTextCompositeCommand{\polhk}{OT1}{e}{\msc@ogonek 0 {.06} e}
\DeclareTextCompositeCommand{\polhk}{OT1}{E}{\msc@ogonek{.35}{.07} E}
\DeclareTextCompositeCommand{\polhk}{OT1}{i}{\msc@ogonek {.2}{.07} i}
\DeclareTextCompositeCommand{\polhk}{OT1}{I}{\msc@ogonek {.2}{.07} I}
\DeclareTextCompositeCommand{\polhk}{OT1}{u}{\msc@ogonek {.6}{.07} u}
\DeclareTextCompositeCommand{\polhk}{OT1}{U}{\msc@ogonek 0 {.05} U}
\DeclareTextCompositeCommand{\polhk}{OT1}{o}{\msc@ogonek 0 {.07} o}
\DeclareTextCompositeCommand{\polhk}{OT1}{O}{\msc@ogonek 0 {.05} O}
% \end{macrocode}
%
% \begin{macrocode}
\DeclareTextCompositeCommand{\polhk}{T1}{i}{\msc@ogonek@a 0 i}
\DeclareTextCompositeCommand{\polhk}{T1}{I}{\msc@ogonek@a 0 I}
\DeclareTextCompositeCommand{\polhk}{T1}{u}{\msc@ogonek@a {.6} u}
\DeclareTextCompositeCommand{\polhk}{T1}{U}{\msc@ogonek@a 0 U}
\DeclareTextCompositeCommand{\polhk}{T1}{o}{\msc@ogonek@a 0 o}
\DeclareTextCompositeCommand{\polhk}{T1}{O}{\msc@ogonek@a 0 O}
% \end{macrocode}
%
% \begin{macrocode}
\DeclareTextCompositeCommand{\polhk}{OT4}{i}{\msc@ogonek {.2}{.07} i}
\DeclareTextCompositeCommand{\polhk}{OT4}{I}{\msc@ogonek {.2}{.07} I}
\DeclareTextCompositeCommand{\polhk}{OT4}{u}{\msc@ogonek {.6}{.07} u}
\DeclareTextCompositeCommand{\polhk}{OT4}{U}{\msc@ogonek 0 {.05} U}
\DeclareTextCompositeCommand{\polhk}{OT4}{o}{\msc@ogonek 0 {.07} o}
\DeclareTextCompositeCommand{\polhk}{OT4}{O}{\msc@ogonek 0 {.05} O}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\msc@ogonek}
% \begin{macrocode}
\def\msc@ogonek#1#2#3{%
\begingroup
\setboxz@h{#3\save@sf}%
\dimen@\wd\z@
\ooalign{%
\unhbox\z@\crcr
\hidewidth
\setboxz@h{\kern#1\dimen@\supsize$\lhook$}%
\dimen@\ht\z@
\advance\dimen@-#2ex\relax
\lower\dimen@\box\z@
\hidewidth
}%
\restore@sf
\endgroup
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\msc@ogonek@a}
% \begin{macrocode}
\def\msc@ogonek@a#1#2{%
\begingroup
\ooalign{%
#2\save@sf\crcr
\hidewidth
\raise0.02ex\hbox{\kern#1ex\char'014}%
\hidewidth
}%
\restore@sf
\endgroup
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\soft}
% Polish `soft' letters T, D, L:
%
% \begin{chartable}
% |\soft{T}| & \soft{T} & \uchar{0164} &
% |\soft{t}| & \soft{t} & \uchar{0165} \\
% |\soft{D}| & \soft{D} & \uchar{010E} &
% |\soft{d}| & \soft{d} & \uchar{010f} \\
% |\soft{L}| & \soft{L} & \uchar{013B} &
% |\soft{l}| & \soft{l} & \uchar{013C}
% \end{chartable}
% \begin{macrocode}
\DeclareTextCommand{\soft}{OT4}{\v}
\DeclareTextCommand{\soft}{T1}{\v}
\DeclareTextCommand{\soft}{OT1}{\v}
\DeclareTextCompositeCommand{\soft}{OT1}{t}{\msc@soft{t}\@ne{.5ex}}
\DeclareTextCompositeCommand{\soft}{OT1}{d}{\msc@soft{d}{.925}{.95ex}}
\DeclareTextCompositeCommand{\soft}{OT1}{l}{\msc@soft{l}{.95}{.4ex}}
\DeclareTextCompositeCommand{\soft}{OT1}{L}{\msc@soft{L}{.975}{.8ex}}
\DeclareTextCompositeCommand{\soft}{OT4}{t}{\msc@soft{t}\@ne{.5ex}}
\DeclareTextCompositeCommand{\soft}{OT4}{d}{\msc@soft{d}{.925}{.95ex}}
\DeclareTextCompositeCommand{\soft}{OT4}{l}{\msc@soft{l}{.95}{.4ex}}
\DeclareTextCompositeCommand{\soft}{OT4}{L}{\msc@soft{L}{.975}{.8ex}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\msc@soft}
% \begin{macrocode}
\def\msc@soft#1#2#3{%
\leavevmode
\begingroup
\setboxz@h{#1}%
\raise#2\ht\z@\rlap{\kern#3\supsize,}\unhbox\z@
\endgroup
}
% \end{macrocode}
% \end{macro}
%
% \section*{\raggedright Appendix: Plumbing the depths of
% underhanging diacritics: Notes on the magic constant 0.2\,ex and
% an exegesis of certain obscure corners of the \cn{@underaccent}
% macro}
%
% \tex/ assumes that a combining accent can be superimposed
% directly on top of any character whose height is 1\,ex. If the
% actual height of the base character differs from 1\,ex, the
% accent is shifted up or down to maintain the same vertical
% separation. Put another way, subtracting 1\,ex from the height
% of a combining accent tells us how much a character's height is
% increased when that accent is added. Call this
% distance~$\delta$.
%
% This distance can be analyzed into two pieces: $\delta = \sigma +
% \eta$, where $\sigma$ is the separation between the top of
% the base character and the \emph{bottom} of the accent, and
% $\eta$ is the height of the bounding box of the accent.
%
% If we now consider moving the accent to the bottom of a
% character, we have a new relation $\delta' = \sigma' + \eta$,
% where $\sigma'$ is the distance between the bottom of the base
% and the \emph{top} of the accent, and $\delta'$ is the amount by
% which the depth of the base character is increased.
%
% If the placement of the underhanging version of an accent were
% strictly symmetrical with the overhanging version, then we would
% have $\sigma' = \sigma$ and thus $\delta' = \delta$. However, the
% placement is not symmetric since for aesthetic reasons we have
% chosen to set $\sigma' = .2\,\mathrm{ex}$, which seems in general
% to be a little less than the corresponding~$\sigma$.
% Unfortunately, this means we can't calculate~$\delta'$ accurately
% since there is no way to deduce $\eta$ (or, equivalently,
% $\sigma$) from the font metric information available to us
% within~\TeX.\footnote{By exploiting symmetries present in some
% fonts, one can calculate $\eta$ for some of the accents in those
% fonts, but this doesn't help us much since both $\sigma$
% and~$\eta$ vary between accents.}
%
% This leaves us in a bit of a bind, since it means there is no way
% to calculate the depth accurately. In despair, I've decided just
% to pretend that $\delta' = \delta$ for now.
%
% \subsection*{Finis}
%
% The usual \cs{endinput} to ensure that random garbage at the end of
% the file doesn't get copied by \fn{docstrip}.
% \begin{macrocode}
\endinput
% \end{macrocode}
%
% \CheckSum{365}
% \Finale
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