% \iffalse
%
% functan.dtx
% Copyright 2004 Antoine Lejay
%
% This program is provided under the terms of the
% LaTeX Project Public License distributed from CTAN
% archives in directory macros/latex/base/lppl.txt.
%
% Author: Antoine Lejay 
% \fi
% \CheckSum{360}
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% \iffalse
%<*dtx>
	\ProvidesFile{functan.dtx}
%</dtx>
%<package>\ProvidesPackage{functan}
%<driver>\ProvidesFile{functan.drv}
% \fi
%	\ProvidesFile{functan.dtx}%
	[2004/07/03 v1.0 Macros for functional analysis]
% \iffalse 
%<*driver>
\documentclass[11pt]{ltxdoc}
\usepackage{functan}
\EnableCrossrefs
\CodelineIndex
\RecordChanges
%%\OnlyDescription
\begin{document}
	\DocInput{functan.dtx}
\end{document}
%</driver>
% \fi
% \def\docdate{July, 13 2004}
% \DoNotIndex{\newcommand,\fi,\def,\else,\edef,\ifx,\let}
% \DoNotIndex{\global,\NeedsTeXFormat,\;,\ProcessOptions,\ProvidesPackage}
% \DoNotIndex{\PassOptionsToPackage}
% \GetFileInfo{functan.dtx}
% \MakeShortVerb{\"}
% \DeleteShortVerb{\|}
% \Macro{L2}{\mathrm{L}^2}
% \Macro{H10}{\mathrm{H}^1_0}
% \Macro{L2Om}{\m{L2}(\Omega)}
% \Macro{H10Om}{\m{H10}(\Omega)}
% \newnorm{aver}{\delonearg[#1]{#2}{\langle}{\rangle}}
% \newconv{*L2Om}{\conv*{\star\text{-}\m{L2Om}}{#1}}
% \newcommand{\itm}{\medskip\noindent The command \ignorespaces}
% \newcommand{\itms}{\medskip\noindent The commands \ignorespaces}
% \newenvironment{examplenotab}{\medskip\hrule\noindent\strut\ignorespaces}{\par\smallskip\hrule}
% \newenvironment{example}{\medskip\hrule\noindent\begin{tabular}{@{\strut}l l}}{\end{tabular}\hrule}
% \newcommand{\event}[2][auto]{\delonearg[#1]{#2}{\{}{\}}}
% \let\package\textsf
% \newcommand{\Nota}{\medskip\noindent\textit{Nota: }\ignorespaces}
%
%
% \title{\package{functan}\thanks{Package version \fileversion{} of 
% \filedate{}.}\\ Macros for functional analysis and related domains}
% \author{Antoine Lejay\\
% $<$\texttt{Antoine.Lejay@iecn.u-nancy.fr}$>$}
% \date{\docdate\\ Printed on \today}
% \maketitle
% \section{Introduction}
% 
% This package is designed especially for the people
% working in domains of mathematics such 
% as functional analysis and PDE theory. Of course, 
% this package may be used in other domains.
% 
% In functional analysis and PDE theory, one may face
% a lot of names of spaces, sometimes depending 
% on one or more parameters, such as $\m{L2Om}$, $\m{H10Om}$, ... 
% Besides, one has to deal 
% with norms, convergence and scalar product 
% for each of these spaces.
% As a control sequence, i.e., a \TeX{} command, consists only 
% of letters, using \TeX's standard macros is not convenient
% for dealing with such spaces. Yet
% composing each of these space names at each their
% occurrence increases the risk of errors, 
% and tends to be tedious.
%
% Fortunately, \TeX{} provides some way to 
% create commands whose name may contain 
% arbitrary characters. We exploit this 
% possibility to deal with names of 
% functional spaces and related objects 
% (norms, convergence, ...).
% 
% This package allows for example to typeset:
% \begin{quote}
% We denote by $\m{L2Om}$ the space of measurable
% functions on $\Omega$ which are square integrable. 
% The associated norm $\norm{L2Om}{\cdot}$ is defined 
% by $\norm{L2Om}{f}=\left(\int_\Omega f(x)^2 dx\right)^{1/2}$
% and the corresponding scalar product is 
% $\scalprod{L2Om}{f}{g}=\int_\Omega f(x)g(x)dx$.
% We write $f_n\conv{L2Om}{n\to\infty}f$ 
% if the sequence $(f_n)_n$ converges to $f$ in $\m{L2Om}$.
% If for all $g\in\m{L2Om}$, $\scalprod{L2Om}{f_n}{g}$
% converges to $\scalprod{L2Om}{f}{g}$, then 
% we say that $(f_n)_n$ converges weakly to $f$
% in $\m{L2Om}$, and we write $f_n\wkconv{L2Om}{n\to\infty}f$.
% \end{quote}
% The code for this example is the following:
% \begin{verbatim}
% \Macro{L2Om}{\mathrm{L}^2(\Omega)}
%
% We denote by $\m{L2Om}$ the space of measurable
% functions on $\Omega$ which are square integrable. 
% The associated norm $\norm{L2Om}{\cdot}$ is defined 
% by $\norm{L2Om}{f}=\left(\int_\Omega f(x)^2 dx\right)^{1/2}$
% and the corresponding scalar product is 
% $\scalprod{L2Om}{f}{g}=\int_\Omega f(x)g(x)dx$.
% We write $f_n\conv{L2Om}{n\to\infty}f$ 
% if the sequence $(f_n)_n$ converges to $f$ in $\m{L2Om}$.
% If for all $g\in\m{L2Om}$, $\scalprod{L2Om}{f_n}{g}$
% converges to $\scalprod{L2Om}{f}{g}$, then 
% we say that $(f_n)_n$ converges weakly to $f$
% in $\m{L2Om}$, and we write $f_n\wkconv{L2Om}{n\to\infty}f$.
% \end{verbatim}
%
% \begin{center}
% \fbox{\begin{minipage}{0.75\textwidth} This package
% uses of some commands of the package
% \package{amsmath} (some of these commands are available 
% only for version \textbf{2.0} or higher), which is then automatically
% loaded. All the options of \package{amsmath}
% may be defined as options of \package{functan}.
% 
% Before using \package{functan}, 
% be sure you have a recent version of \package{amsmath}
% installed in your computer.
% \end{minipage}}
% \end{center}
%
% \section{Loading the package}
%
% This package is loaded as any package by the command 
% "\usepackage". This package has no options, except
% those of \package{amsmath} in order to avoir 
% an option clash. Thus, the possible options 
% are: 
% "leqno",
% "intlimits",
% "nointlimits",
% "sumlimits",
% "nosumlimits",
% "namelimits",
% "nonamelinits",
% "reqno",
% "centertags",
% "tbtags",
% "cmex10" and 
% "fleqn".
% 
% \medskip
%
% \noindent\textbf{Incompatibilities : } This package 
% has no known incompatibilities with other packages.
%
% \section{The commands}
%
% \subsection{An alternative system of macros}
% 
% This system consists in associating a sequence
% of tokens to a name by the command "\Macro",
% and call it later by the command "\m".
%
% 
% \itm "\Macro"\marg{name}\marg{expansion} 
% \DescribeMacro{\Macro}
% associates the list of tokens \meta{expansion}
% to the list of tokens
% \meta{name}, which may contain any arbitrary 
% sequence of characters (except~"{", "}" and 
% active characters). This macro produces 
% a warning message ``The macro `\meta{name}' has 
% already been defined'' if \meta{name} already exists.
%
% \Nota The sequence \meta{name} may correspond to the control
% sequence of a \TeX{} macro without creating interferences.
% Internally, the system stores the expansion 
% of \meta{name} as the \TeX{} control sequence 
% "functan@macro@"\meta{name}.
%
% \itm "\m"\marg{name} gives the expansion corresponding
% \DescribeMacro{\m}
% to \meta{name} if a couple \meta{name} and \meta{expansion}
% has already been defined by 
% "\Macro". Otherwise, an error message 
% ``The macro `\meta{name}' is not defined'' is produced.
% The error message ``No macro's name given'' is 
% also produced if the argument is given, that is 
% if "\m{}" is encountered.
% 
% 
% \begin{examplenotab}
% "\Macro{L2Om}{\mathrm{L}^2(\Omega)}"\\
% "Denote by  $\m{L2Om}$ the space of functions such that..."\\
% \hbox{}\quad 
% Denote by  $\m{L2Om}$ the space of functions such that...
% \end{examplenotab}
% 
% \Nota A command "\mempty"
% is also defined whose action is similar to 
% "\m", except that it does not produce
% an error message if its argument is empty. 
%
% \subsection{Norms}
%
% The command "\norm" allows to typeset 
% norms easily. 
% \begin{table}
% \begin{center}
% \begin{tabular}{l l l l l l}
% \hline
% (empty string) & \texttt{auto} & 
% \texttt{big} & \texttt{Big} & \texttt{bigg} & \texttt{Bigg}\\
% \hline
% \end{tabular}
% \caption{\label{table-1} Possible arguments for the size}
% \end{center}
% \end{table}
% 
% \itm "\norm"\oarg{size}\marg{name}\marg{arg}
% \DescribeMacro{\norm}
% is roughly an equivalent to "\|"\meta{arg}"\|_{\m"\marg{name}"}"
% but with a control on the size of the vertical bars.
% If \meta{name} is empty, 
% then nothing is put in subscript. 
% The optional argument \meta{size} is one of the 
% element in Table~\ref{table-1}. 
% By default, \meta{size} is set to \texttt{auto}, 
% which is equivalent in using "\left\|"..."\right\|"
% around \meta{arg}.
% If \meta{size} is empty, that is when one call 
% "\norm[]{...}{...}", then the delimitor $\|$ 
% is used with its normal size. If \meta{size} is equal to 
% \texttt{big}, \texttt{Big}, \texttt{bigg} or \texttt{Bigg}, 
% then \meta{size} is inserted before the delimitors $\|$.
%
% \Nota If \meta{size} is not one of the elements of Table~\ref{table-1},
% the the normal size is used.
% 
% \begin{example}
% "\norm{}{f}" &  $\norm{}{f}$\\
% "\norm{L2Om}{f}" & $\norm{L2Om}{f}$\\
% "\norm[Big]{L2Om}{f}" & $\norm[Big]{L2Om}{f}$\\
% "\norm{L2Om}{\frac{1}{f}}" & $\norm{L2Om}{\frac{1}{f}}$\\
% "\norm[]{L2Om}{\frac{1}{f}}" & $\norm[]{L2Om}{\frac{1}{f}}$\\
% \end{example}
% 
% \itm "\norm*"\oarg{size}\marg{subscr}\marg{arg}
% \DescribeMacro{\norm*}
% works as "\norm", except that \meta{subscr} is not 
% one of the macro defined by "\Macro", 
% but any sequence of tokens which is put in subscript.
% For example "\norm*{\infty}{f}" is equivalent 
% to "\norm{}{f}_{\infty}".
%
% \begin{example}
% "\norm*{\infty}{f}" & $\norm*{\infty}{f}$\\
% "\norm*[Big]{\infty}{f}" & $\norm*[Big]{\infty}{f}$\\
% \end{example}
% 
% \itm "\newnorm"\marg{name}\marg{expansion}
% \DescribeMacro{\newnorm}
% allows to override the behavior of the "\norm" macro.
% Instead of using a "\|"..."\|" 
% structure, the user may for example use other delimitors.
% Here \meta{name} is any sequence of tokens (except 
% "{", "}" and active characters), already 
% defined by "\Macro" or not.
% The arguments "#1" (for the size) et "#2" (for the argument) may be 
% used in \meta{expansion}. The macros 
% "\casesize" and "\delonearg" (see Section~\ref{sub-macro} below)
% may be used to create some new kind of norms. 
%
% \newnorm{L2Om}{\delonearg[#1]{#2}{|}{|}}
% \begin{example}
% "\newnorm{L2Om}{\delonearg[#1]{#2}{|}{|}}"  \\
% "\norm{L2Om}{f}" &  $\norm{L2Om}{f}$\\
% "\norm[Big]{L2Om}{f}" &  $\norm[Big]{L2Om}{f}$\\
% \end{example}
% 
% \Nota It seems that some side effects 
% appear when "\newnorm" is used inside a group. 
% Hence, it is recommended to use this command 
% in the preamble.
% 
% 
%
% \subsection{Scalar products}
% 
% Macros for scalar products are similar to 
% macros for the norms, except that two 
% argument are needed.
% 
% \itm "\scalprod"\oarg{size}\marg{name}\marg{arg 1}\marg{arg 2} 
% \DescribeMacro{\scalprod}
% creates roughly 
% "\langle"\meta{arg 1}","\meta{arg 2}"\rangle_{\m"\marg{name}"}".
% The optional 
% \meta{size} argument shall be taken in Table~\ref{table-1},
% and acts as a modifier for the size of the brackets.
%
% \begin{example}
% "\scalprod{}{f}{g}" & $\scalprod{}{f}{g}$\\
% "\scalprod{L2Om}{f}{g}" & $\scalprod{L2Om}{f}{g}$\\
% "\scalprod{L2Om}{f}{\frac{1}{g}}" & $\scalprod{L2Om}{f}{\frac{1}{g}}$\\
% "\scalprod[big]{L2Om}{f}{\frac{1}{g}}" & $\scalprod[big]{L2Om}{f}{\frac{1}{g}}$
% \end{example}
% 
% \itm "\scalprod*"\oarg{size}\marg{subscr}\marg{arg 1}\marg{arg 2} 
% \DescribeMacro{\scalprod*}
% acts like "\scalprod", except that \meta{subscr} is 
% not the name already defined by "\Macro", but 
% a sequence of tokens put in subscript after the closing 
% bracket. The rules are the same as for "\norm".
%
% \begin{example}
% "\scalprod*{X,Y}{Ax}{y}" & $\scalprod*{X,Y}{Ax}{y}$\\
% "\scalprod*{X,Y}{B^{-1}x}{y}" & $\scalprod*{X,Y}{B^{-1}x}{y}$\\
% "\scalprod*[]{X,Y}{B^{-1}x}{y}" & $\scalprod*[]{X,Y}{B^{-1}x}{y}$
% \end{example}
% 
% \itm "\newscalprod"\marg{name}\marg{expansion}
% \DescribeMacro{\newscalprod}
% allows to override the behavior of "\scalprod",
% as for "\newnorm". Here, \meta{expansion} may 
% used the three arguments "#1" (for the optional size), 
% "#2" (\meta{arg 1}) and "#3" (\meta{arg 2}).
% The command "\towarg" (see Section~\ref{sub-macro} below)
% may be used to help the user to deal with new types
% of scalar products.
%
% \newscalprod{L2}{\deltwoarg[#1]{#2}{#3}{(}{)}{|}}
% \begin{examplenotab}
% \noindent\strut"\newscalprod{L2Om}{\deltwoarg[#1]{#2}{#3}{(}{)}{|}}" 
% 
% \noindent\begin{tabular}{@{\strut} l l}
% "\scalprod{L2}{f}{g}" & $\scalprod{L2}{f}{g}$ \\
% "\scalprod[Big]{L2}{f}{g}" & $\scalprod[Big]{L2}{f}{g}$\\
% "\scalprod[]{L2}{f^2}{g^2}" & $\scalprod[]{L2}{f^2}{g^2}$
% \end{tabular}
% \end{examplenotab}
% 
% \Nota It seems that some side effects 
% appear when "\newnorm" is used inside a group. 
% Hence, it is recommended to used this command 
% in the preamble.
% 
% \subsection{Convergence}
% The package \package{amsmath} provides a way 
% to create \emph{extensible arrows}, whose
% size depends on the material put above and 
% below the arrow.
% 
% \itm "\conv"\marg{name}\marg{below}
% \DescribeMacro{\conv}
% creates an extensible arrow by putting the 
% expansion of \meta{name} above the arrow, 
% and \meta{below} under the arrow. 
% This command uses the commands "\xrightarrow" of 
% \package{amsmath}. However, the "\xrightarrow" command 
% takes as an optional argument the material to be put 
% below. Here, it is a mandatory second argument.
% 
% \begin{example}
% "x_n\conv{}{} x" & $x_n\conv{}{} x$\\
% "f_n\conv{}{n\to\infty} f" & $f_n\conv{}{n\to\infty} f$\\
% "f_n\conv{L2Om}{n\to\infty} f" & $f_n\conv{L2Om}{n\to\infty} f$\\
% \end{example}
% 
% \itm "\conv*"\marg{above}\marg{below}
% \DescribeMacro{\conv*}
% is similar to "\conv", except that both 
% \meta{above} and \meta{below} are lists of tokens
% that are put respectively above and below the arrow.
%
% \begin{example}
% "f_n\conv*{\text{uniformly}}{n\to\infty} f" & $f_n\conv*{\text{uniformly}}{n\to\infty} f$
% \end{example}
% 
% \itm "\newconv"\marg{name}\marg{expansion} allows
% \DescribeMacro{\newconv}
% to override the behavior of "\conv"\marg{name}, 
% whether \meta{name} corresponds to a name 
% defined by "\Macro" or not. The token list 
% \meta{expansion} may use one argument "#1".
%
% \begin{examplenotab}
% "\newconv{*L2Om}{\conv*{\star\text{-}\m{L2Om}}{#1}}"\\
% "f_n\conv{*L2Om}{n\to\infty} f" \quad $f_n\conv{*L2Om}{n\to\infty}f$\\
% \end{examplenotab}
% 
% \itms "\leftconv"\marg{name}\marg{below} 
% \DescribeMacro{\leftconv}
% \DescribeMacro{\leftconv*}
%\\ and "\leftconv*"\marg{above}\marg{below} 
% act like "\conv" and "\conv*", except that 
% an arrow pointing to the left ($\leftconv{}{}$) is used instead
% of an arrow pointing to the right ($\conv{}{}$).
%
% \itms "\leftrightconv"\marg{name}\marg{below}
% \DescribeMacro{\leftrightconv}
% \DescribeMacro{\leftrightconv*}
% \\and "\leftrightconv*"\marg{above}\marg{below} 
% act like "\conv" and "\conv*", except that 
% an arrow pointing both to the left and to
% the right ($\leftrightconv{}{}$) is used instead
% of an arrow pointing to the right ($\conv{}{}$).
% 
% 
% There are other commands similar to "\conv", 
% "\conv*", "\leftconv", "\leftconv*",
% "\leftrightconv" and "\leftrightconv*"
% that is with the same arguments, but with 
% different types of arrows. 
% 
% \itms "\wkconv", "\wkconv*", "\leftwkconv",
% \DescribeMacro{\wkconv}
% \DescribeMacro{\wkconv*}
% \DescribeMacro{\leftwkconv}
% \DescribeMacro{\leftwkconv*}
% \DescribeMacro{\leftrightwkconv}
% \DescribeMacro{\leftrightwkconv*}
% "\leftwkconv*",\\
% "\leftrightwkconv" and "\leftrightwkconv*"
% use $\wkconv{}{}$ instead of~$\conv{}{}$. Such an arrow 
% is generally used to denote \emph{weak convergence}
% (hence the "wk").
%
% \begin{example}
% "f_n\wkconv{}{n\to\infty} f" & 
% $f_n\wkconv{}{n\to\infty} f$\\
% "f_n\wkconv{H10}{n\to\infty} f" & 
% $f_n\wkconv{H10}{n\to\infty} f$
% \end{example}
%
% \itms "\Conv", "\Conv*", "\Leftconv", "\Leftconv*",
% \DescribeMacro{\Conv}
% \DescribeMacro{\Conv*}
% \DescribeMacro{\Leftconv}
% \DescribeMacro{\Leftconv*}
% \DescribeMacro{\Leftrightconv}
% \DescribeMacro{\Leftrightconv*}
% "\Leftrightconv" and "\Leftrightconv*"
% use $\Conv{}{}$ instead of~$\conv{}{}$. 
% This may be used to denote convergence in 
% distribution in probability theory.
% This could also be used for the implication 
% and equivalence symbols in logic.
% \begin{examplenotab}
% "\mu_n\Conv{}{n\to\infty} \mu" \quad 
% $\mu_n\Conv{}{n\to\infty} \mu$\\
% "x<0\Leftrightconv*{\text{Lemma 1.1}}{} f(x)\geq 0"\\
% \hbox{}\quad $x<0\Leftrightconv*{\text{Lemma 1.1}}{} f(x)\geq 0$
% \end{examplenotab}
% 
% \subsection{Defining macros}
% 
% \label{sub-macro}
%
% The package \package{functan} provides a few 
% macros to help the user to define its own
% norms, scalar products, ...
% 
% \itm "\delonearg"\oarg{size}\marg{arg}\marg{left del}\marg{right del} 
% \DescribeMacro{\delonearg}
%\\ surrounds \meta{arg} the left delimitor 
% \meta{left del} and the right delimitor \meta{right del}.
% The possible values of the optional argument \meta{size} (which is by 
% default set to "auto") are given in Table~\ref{table-1}.
% \newcommand{\ket}[2][auto]{\delonearg[#1]{#2}{|}{\rangle}}
% \newcommand{\bra}[2][auto]{\delonearg[#1]{#2}{\langle}{|}}
% \begin{examplenotab}
% "\newcommand{\event}[2][auto]{\delonearg[#1]{#2}{\{}{\}}}"\\
% "\event{1,\dotsc,\frac{1}{n}}"\\
% "\cup\event[]{\frac{1}{n^2},\dotsc,\frac{2}{n^2}}"\\
% \hbox{}\quad$\event{1,\dotsc,\frac{1}{n}}\cup\event[]{\frac{1}{n},\dotsc,\frac{2}{n}}$\\
% "\newcommand{\ket}[2][auto]{\delonearg[#1]{#2}{|}{\rangle}}"\\
% "\ket{Ax}" \quad $\ket{Ax}$\\
% "\newcommand{\bra}[2][auto]{\delonearg[#1]{#2}{\langle}{|}}"\\
% "\bra{Ax}" \quad $\bra{Ax}$
% \end{examplenotab}
%
% \itm "\deltwoarg"\oarg{size}\marg{arg 1}\marg{arg 2}...
% \DescribeMacro{\deltwoarg}
% \\...\marg{left del}\marg{right del}\marg{sep}
% is similar to "\delonearg", except that it 
% separates \meta{arg 1} and \meta{arg 2}
% by a separator \meta{sep.}. If
% \meta{sep} is set to "|", then a vertical bar
% is used, with an automatic adjustment to the size
% of the delimitors.
%
% \newcommand{\set}[3][auto]{\deltwoarg[#1]{#2}{#3}{\{}{\}}{\,;\,}}
% \newcommand{\braket}[3][auto]{\deltwoarg[#1]{#2}{#3}{\langle}{\rangle}{|}}
% \begin{examplenotab}
% "\newcommand{\set}[3][auto]{\deltwoarg[#1]{#2}{#3}{\{}{\}}{\,;\,}}"\\
% "\set{x\geq 0}{P(x)=0}" \quad $\set{x\geq 0}{P(x)=0}$\\
% "\newcommand{\braket}[3][auto]{%"\\
% "\deltwoarg[#1]{#2}{#3}{\langle}{\rangle}{|}}"\\
% "\braket{Ax}{y}" \quad $\braket{Ax}{y}$
% \end{examplenotab}
% 
% \itm "\casesize"\marg{size}\marg{auto}\marg{empty}...
% \DescribeMacro{\casesize}
%\\...\marg{big}\marg{Big}\marg{bigg}\marg{Bigg}
% takes \meta{size} in Table~\ref{table-1} 
% and executes \marg{empty} if \meta{size} is an empty 
% list of tokens, \meta{auto} if \meta{size} is "auto",
% \meta{big} if \meta{size} is "big", ...
% The error message ``Size argument `\meta{size}' of `casesize' not valid''
% is produced if \meta{size} is not in Table~\ref{table-1}
% 
% \itm "\delcasesize"\marg{size}\marg{auto}\marg{empty}\marg{other}
% \DescribeMacro{\delcasesize}
% is similar to "\casesize", except that \meta{other} is 
% executed if \meta{size} is different from "auto" 
% or from an empty list of tokens.
%
%
% \section{Examples}
%
% \subsection{Macros with arguments}
% 
% It is possible to define a macro \meta{name}
% such that "\m"\marg{name} accepts some arguments. 
% For that, it is sufficient 
% that it expands into a \TeX{} command 
% that accepts arguments.
% 
% \newcommand{\evolution}[2]{\m{#1}(0,T;\m{#2})}
% \Macro{L20T}{\evolution{L2}}
% \begin{examplenotab}
% "\newcommand{\evolution}[2]{\m{#1}(0,T;\m{#2})}"\\
% "\Macro{L20T}{\evolution{L2}}"\\
% "\m{L20T}{H10Om}\cap\m{L20T}{L2Om}"\quad
% $\m{L20T}{H10Om}\cap\m{L20T}{L2Om}$
% \end{examplenotab}
% 
% 
% \subsection{Matrix norms}
%\newnorm{matrix}{\delcasesize{#1}%
%{\left|\left|\left| #2\right|\right|\right|}%
%{|||#2|||}%
%{#1|#1|#1|#2 #1|#1|#1|}}
% 
% A matrix norm with three bars may be 
% defined by 
%\begin{verbatim}
%\newnorm{matrix}{\delcasesize{#1}%
%{\left|\left|\left| #2\right|\right|\right|}%
%{|||#2|||}%
%{#1|#1|#1|#2 #1|#1|#1|}}
%\end{verbatim}
% so that 
% \begin{examplenotab}
% "\norm{matrix}{A^2}\leq \norm{matrix}{A}^2"\quad
% $\norm{matrix}{A^2}\leq \norm{matrix}{A}^2$\\
% "\norm[]{matrix}{A^2}\leq \norm{matrix}{A}^2"\quad
% $\norm[]{matrix}{A^2}\leq \norm{matrix}{A}^2$
% \end{examplenotab}
%
% \subsection{Sets}
%
% An example of code for defining sets was given 
% with the documentation of "\deltwoarg". Here is 
% another possibility
% \newcommand{\settwo}[3][auto]{\deltwoarg[#1]{#2\,}{\,#3}{\{}{\}}{|}}
% \begin{examplenotab}
% "\newcommand{\set}[3][auto]{%"\\
% "\deltwoarg[#1]{#2\,}{\,#3}{\{}{\}}{|}}"\\
% "\set{x>-1}{\frac{x}{1+x}\geq \frac{1}{2}}"\quad 
% $\displaystyle \settwo{x>-1}{\frac{x}{1+x}\geq \frac{1}{2}}$ 
% \end{examplenotab}
%
% \subsection{Duality products}
%
% The command "\casesize" may be used for defining
% a duality product, which is a bit tricky since 
% we want the position of name of the dual space 
% to be adjusted to the size of the delimitors.
% The command "\dual" defined by
% 
%\newcommand{\dual}[5][auto]{
%\casesize{#1}{
%\left.\vphantom{\left\langle #4;#5\right\rangle}%
%\right._{\m{#2}}\left.%
%\left\langle #4;#5\right\rangle\right._{\m{#3}}}%
%{{}_{\m{#2}}\langle #4;#5\rangle_{\m{#3}}}%
%{\bigl._{\m{#2}}\bigl\langle #4;#5\bigr\rangle_{\m{#3}}}%
%{\Bigl._{\m{#2}}\Bigl\langle #4;#5\Bigr\rangle_{\m{#3}}}%
%{\biggl._{\m{#2}}\biggl\langle #4;#5\biggr\rangle_{\m{#3}}}%
%{\Biggl._{\m{#2}}\Biggl\langle #4;#5\Biggr\rangle_{\m{#3}}}}
% \begin{verbatim}
%\newcommand{\dual}[5][auto]{
%\casesize{#1}{
%\left.\vphantom{\left\langle #4;#5\right\rangle}%
%\right._{\m{#2}}\left.%
%\left\langle #4;#5\right\rangle\right._{\m{#3}}}%
%{{}_{\m{#2}}\langle #4;#5\rangle_{\m{#3}}}%
%{\bigl._{\m{#2}}\bigl\langle #4;#5\bigr\rangle_{\m{#3}}}%
%{\Bigl._{\m{#2}}\Bigl\langle #4;#5\Bigr\rangle_{\m{#3}}}%
%{\biggl._{\m{#2}}\biggl\langle #4;#5\biggr\rangle_{\m{#3}}}%
%{\Biggl._{\m{#2}}\Biggl\langle #4;#5\Biggr\rangle_{\m{#3}}}}
% \end{verbatim}
% may be used to produce
% \Macro{H1}{\mathrm{H}^1}
% \Macro{H-1}{\mathrm{H}^{-1}}
% \begin{example}
% "\Macro{H1}{\mathrm{H}^1}"\\
% "\Macro{H-1}{\mathrm{H}^{-1}}"\\
% "\dual{H-1}{H1}{f}{\frac{1}{g}}" & 
% $\dual{H-1}{H1}{f}{\frac{1}{g}}$\\
% "\dual[]{H-1}{H1}{f}{\frac{1}{g}}" &
% $\dual[]{H-1}{H1}{f}{\frac{1}{g}}$\\
% "\dual[bigg]{H-1}{H1}{f}{\frac{1}{g}}" & 
% $\dual[bigg]{H-1}{H1}{f}{\frac{1}{g}}$
% \end{example}
%
%
%
%
% \section{The code}
%
% \subsection{Package heading}
% This package uses some code of the \package{amsmath} package.
% All the options of \package{amsmath} may 
% be set as options of \package{functan} in 
% order to avoir an option clash.
%    \begin{macrocode}
%<*package>
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{functan}[2004/07/03 v1.0, Macros for functional analysis]
\DeclareOption{leqno}{%
\PassOptionsToPackage{leqno}{amsmath}}
\DeclareOption{intlimits}{%
\PassOptionsToPackage{intlimits}{amsmath}}
\DeclareOption{nointlimits}{%
\PassOptionsToPackage{leqno}{amsmath}}
\DeclareOption{sumlimits}{%
\PassOptionsToPackage{sumlimits}{amsmath}}
\DeclareOption{nosumlimits}{%
\PassOptionsToPackage{leqno}{amsmath}}
\DeclareOption{namelimits}{%
\PassOptionsToPackage{namelimits}{amsmath}}
\DeclareOption{nonamelinits}{%
\PassOptionsToPackage{nonamelinits}{amsmath}}
\DeclareOption{reqno}{%
\PassOptionsToPackage{reqno}{amsmath}}
\DeclareOption{centertags}{%
\PassOptionsToPackage{centertags}{amsmath}}
\DeclareOption{tbtags}{%
\PassOptionsToPackage{tbtags}{amsmath}}
\DeclareOption{cmex10}{%
\PassOptionsToPackage{cmex10}{amsmath}}
\DeclareOption{fleqn}{%
\PassOptionsToPackage{fleqn}{amsmath}}
\ProcessOptions
\RequirePackage{amsmath}[2000/01/01 v2.0]
%    \end{macrocode}
% \subsection{Defining macros}
%
% \begin{macro}{\Macro}
% This commands defines a new macro with 
% name \meta{name}, by creating 
% a \TeX{} command \verb+functan@macro@+\meta{name}.
% A warning message is sent if \meta{name} has already 
% been defined.
%    \begin{macrocode}
\newcommand{\Macro}[2]{\@ifundefined{functan@macro@#1}{}{%
\PackageWarning{functan}{The macro '#1' has already been defined}}
\@namedef{functan@macro@#1}{#2}}
%    \end{macrocode}
% \end{macro}
% \begin{macro}{\m}
% \begin{macro}{\mempty}
% This command allows to call the macro defined by \meta{name}.
% An error message is sent if \meta{name} has not been 
% defined, or if no argument is given.
% The macro \verb+\mempty+ provides no error 
% message is the argument is empty. It is used 
% to deal with \verb+\conv+ macros.
%    \begin{macrocode}
\newcommand{\m}[1]{\@ifempty{#1}{%
\PackageError{functan}{No macro's name given}{}
}{%
\@ifundefined{functan@macro@#1}{%
\PackageError{functan}{The macro `#1' is not defined}{}}{%
\@nameuse{functan@macro@#1}}}}
\newcommand{\mempty}[1]{\@ifempty{#1}{}{%
\@ifundefined{functan@macro@#1}{%
\PackageError{functan}{The macro `#1' is not defined}{}}{%
\@nameuse{functan@macro@#1}}}}
%    \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \subsection{Dealing with size}
% \begin{macro}{\functan@casesize}
% \begin{macro}{\delcasesize}
% The macro "\delcasesize" is an alias for "\functan@casesize".
% These macros require four arguments. This first one 
% is the size among $\emptyset$ (empty argument for normal size)
% \texttt{auto} and one of the delimitors possible
% size (\texttt{big}, \texttt{Big}, \texttt{bigg}, \texttt{Bigg}).
% It \texttt{auto} is detected, then the second argument 
% is executed. It no argument is given, then the third
% argument is executed. Otherwise, the fourth argument
% is executed. 
% Another macro, "\casesize" (see below), is intended 
% to execute a different code the the six distinct possibilities
% ($\emptyset$, \texttt{auto}, 
% \texttt{big}, \texttt{Big}, \texttt{bigg}, \texttt{Bigg}).
%    \begin{macrocode}
\global\def\functan@size@auto{auto}
\newcommand{\functan@casesize}[4]{\def\functan@size{#1}%
\ifx\functan@size\functan@size@auto #2\else%
\@ifempty{#1}{#3}{#4}\fi}
\let\delcasesize\functan@casesize
%    \end{macrocode}
% \end{macro}
% \end{macro}
% \begin{macro}{\casesize}
% The first argument is one of the delimitor's size 
% specification (\texttt{auto}, $\emptyset$,
% \texttt{big}, \texttt{Big}, \texttt{bigg}, \texttt{Bigg}),
% and the six others are the different codes
% for each of the possible size in the order given just above.
%    \begin{macrocode}
\global\def\functan@size@big{big}
\global\def\functan@size@Big{Big}
\global\def\functan@size@bigg{bigg}
\global\def\functan@size@Bigg{Bigg}
\newcommand{\casesize}[7]{%
\def\functan@size{#1}
\@ifempty{#1}{#3}{%
\ifx\functan@size\functan@size@auto{#2}\else%
\ifx\functan@size\functan@size@big{#4}\else%
\ifx\functan@size\functan@size@Big{#5}\else%
\ifx\functan@size\functan@size@bigg{#6}\else%
\ifx\functan@size\functan@size@Bigg{#7}\else%
\PackageError{functan}{Size argument `#1' of `casesize' not valid}%
\fi\fi\fi\fi\fi}}
%    \end{macrocode}
% \end{macro}
% \begin{macro}{\delonearg}
% \begin{macro}{\deltwoarg}
% These two macros may be used for defining a pair
% of delimitors with automatic or manual size adjustment.
%
% \Nota A "big-g-g" argument is transformed 
% into \TeX{} control sequence with the command 
% "\@nameuse". If the argument of \@nameuse
% is not a control sequence for an already defined 
% control sequence, then "\@nameuse"\marg{...} 
% is transformed into an empty list.
%    \begin{macrocode}
\newcommand{\delonearg}[4][auto]{%
\functan@casesize{#1}{\left#3 #2 \right#4}{%
#3 #2 #4}{\@nameuse{#1l}#3 #2 \@nameuse{#1r}#4}}
\newcommand{\deltwoarg}[6][auto]{%
\def\functan@vert@bar{|}%
\edef\functan@arg@bar{#6}%
\ifx\functan@arg@bar\functan@vert@bar%
\functan@casesize{#1}{\left#4 #2\;\vrule\; #3\right#5}{%
#4 #2\;\vert\;#3 #5}{%
\@nameuse{#1l}#4 #2\;\@nameuse{#1}\vert\;#3 \@nameuse{#1r}#5}
\else
\functan@casesize{#1}{\left#4 #2 #6 #3 \right#5}{%
#4 #2 #6 #3  #5}{%
\@nameuse{#1l}#4  #2 #6 #3 \@nameuse{#1r}#5}
\fi}
%    \end{macrocode}
% \end{macro}
% \end{macro}
% \subsection{Norms}
% \begin{macro}{\functan@norm}
% This is the generic macro for the norms, which 
% uses double bars $\Vert$ as delimitors.
%    \begin{macrocode}
\newcommand{\functan@norm}[3]{%
\functan@casesize{#1}{\left\lVert #3\right\rVert%
\@ifnotempty{#2}{_{#2}}}{%
\lVert #3\rVert\@ifnotempty{#2}{_{#2}}}{%
\@nameuse{#1l}\lVert #3\@nameuse{#1r}\rVert%
\@ifnotempty{#2}{_{#2}}}}
%    \end{macrocode}
% \end{macro}
% \begin{macro}{\functan@starred@norm}
% \begin{macro}{\functan@nonstarred@norm}
% This two macros call the command 
% "\functan@norm" either with (non-starred form)
% or without (starred form) expending the second 
% argument \meta{name} as the name of a macro defined by "\Macro".
% Note that if the second argument is empty 
% in "\functan@nonstarred@norm", then 
% no error message is produced. This allows 
% to have a subscript just after the norm
% such as in "\norm{}{f}_1"
% without producing an error message 
% of type ``double subscript error''. Note
% that the previous example may also be 
% written "\norm*{1}{f}".
% For the non-starred version, 
% if a \TeX{} macro 
% "functan@named@norm@"\meta{name}
% exists (which is defined by "\newnorm"), 
% then this macro is called instead 
% of \verb+\functan@norm+.
%    \begin{macrocode}
\newcommand{\functan@starred@norm}[3][auto]{%
\functan@norm{#1}{#2}{#3}}
\newcommand{\functan@nonstarred@norm}[3][auto]{%
\@ifundefined{functan@named@norm@#2}%
{\@ifempty{#2}{\functan@norm{#1}{}{#3}}{%
\functan@norm{#1}{\m{#2}}{#3}}}%
{\@nameuse{functan@named@norm@#2}{#1}{#3}}}
%    \end{macrocode}
% \end{macro}
% \end{macro}
% \begin{macro}{\newnorm}
% This macro allows to override the 
% behavior of the "\norm" macro
% by defining a \TeX{} command 
% "functan@named@norm@"\meta{name}.
%    \begin{macrocode}
\newcommand{\newnorm}[1]{%
\@namedef{functan@named@norm@#1}##1##2}
%    \end{macrocode}
% \end{macro}
% \begin{macro}{\norm} This macro is the
%one which is finally used. The presence 
%of a star "*" is checked 
%and either "\functan@starred@norm" or  
%"\functan@nonstarred@norm" is called in 
%consequence.
%    \begin{macrocode}
\newcommand{\norm}{\@ifstar{\functan@starred@norm}%
{\functan@nonstarred@norm}}
%    \end{macrocode}
% \end{macro}
%
%
% \subsection{Convergence}
%
% \Nota It is for this set of macros that 
% the compatibility with version 2.0 of "amsmath"
% or higher is important.
%
% \begin{macro}{\newconv} This macro 
% allows to override the behavior of the 
% \verb+\conv+ macro, by defining a 
% \TeX{} control sequence "functan@named@conv@"\meta{name}.
%    \begin{macrocode}
\newcommand{\newconv}[1]{%
\@namedef{functan@named@conv@#1}##1}
%    \end{macrocode}
% \end{macro}
% \begin{macro}{\conv} 
% This macros stands for the usual convergence
% symbol ($\rightarrow$). The presence of a star 
% \verb+*+ is checked, and either
% \verb+\functan@nonstarred@conv+ 
% or \verb+\functan@starred@conv+ is called in consequence.
% If a \TeX{} command called 
% \verb+functan@named@conv@+\meta{name} exists, 
% where \meta{name} is the first argument of \verb+\conv+,
% then this command is called instead of the others.
%
% The command \verb+\xrightarrow+ is defined 
% in the \package{amsmath} package.
%    \begin{macrocode}
\newcommand{\conv}{%
\@ifstar{\functan@starred@conv}{\functan@nonstarred@conv}}
\newcommand{\functan@nonstarred@conv}[2]{%
\@ifundefined{functan@named@conv@#1}%
{\xrightarrow[#2]{\mempty{#1}}}{\@nameuse{functan@named@conv@#1}{#2}}}
\newcommand{\functan@starred@conv}[2]{\xrightarrow[#2]{#1}}
%    \end{macrocode}
% \end{macro}
% \begin{macro}{\xleftrightglobalarrow}
% \begin{macro}{\Xleftrightglobalarrow}
% \begin{macro}{\Xrightglobalarrow}
% \begin{macro}{\Xleftglobalarrow}
% These commands are defined in a way similar to the
% one in \verb+\xrightarrow+ in the package \package{amsmath}.
% The first four arguments are lengths added on each 
% side of the argument.
%    \begin{macrocode}
\newcommand{\xleftrightarrow}[2][]{%
\ext@arrow 9999\leftrightarrowfill@{#1}{#2}}
\newcommand{\Xrightarrow}[2][]{%
\ext@arrow 0359\Rightarrowfill@{#1}{#2}}
\newcommand{\Xleftarrow}[2][]{%
\ext@arrow 3095\Leftarrowfill@{#1}{#2}}
\newcommand{\Xleftrightarrow}[2][]{%
\ext@arrow 9999\Leftrightarrowfill@{#1}{#2}}
%    \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
% \begin{macro}{\leftconv}
% \begin{macro}{\leftrightconv}
% The commands \verb+\leftconv+ and \verb+\leftrightconv+ are defined 
% as the command \verb+\conv+, except that it
% is not possible to override them (however, 
% any kind of arrow may be used with the command 
% \verb+\newconv+).
%    \begin{macrocode}
\newcommand{\leftconv}{%
\@ifstar{\functan@starred@leftconv}%
{\functan@nonstarred@leftconv}}
\newcommand{\functan@nonstarred@leftconv}[2]{%
\xleftarrow[#2]{\mempty{#1}}}
\newcommand{\functan@starred@leftconv}[2]{%
\xleftarrow[#2]{#1}}
\newcommand{\leftrightconv}{%
\@ifstar{\functan@starred@leftrightconv}%
{\functan@nonstarred@leftrightconv}}
\newcommand{\functan@nonstarred@leftrightconv}[2]{%
\xleftrightarrow[#2]{\mempty{#1}}}
\newcommand{\functan@starred@leftrightconv}[2]{%
\xleftrightarrow[#2]{#1}}
%    \end{macrocode}
% \end{macro}
% \end{macro}
% \begin{macro}{\Conv}
% \begin{macro}{\Leftconv}
% \begin{macro}{\Leftrightconv}
% These macros are defined like \verb+\conv+.
%    \begin{macrocode}
\newcommand{\Conv}{%
\@ifstar{\functan@starred@Conv}{\functan@nonstarred@Conv}}
\newcommand{\functan@nonstarred@Conv}[2]{%
\Xrightarrow[#2]{\mempty{#1}}}
\newcommand{\functan@starred@Conv}[2]{%
\Xrightarrow[#2]{#1}}
\newcommand{\Leftconv}{%
\@ifstar{\functan@starred@Leftconv}%
{\functan@nonstarred@Leftconv}}
\newcommand{\functan@nonstarred@Leftconv}[2]{%
\Xleftarrow[#2]{\mempty{#1}}}
\newcommand{\functan@starred@Leftconv}[2]{%
\Xleftarrow[#2]{#1}}
\newcommand{\Leftrightconv}{%
\@ifstar{\functan@starred@Leftrightconv}%
{\functan@nonstarred@Leftrightconv}}
\newcommand{\functan@nonstarred@Leftrightconv}[2]{%
\Xleftrightarrow[#2]{\mempty{#1}}}
\newcommand{\functan@starred@Leftrightconv}[2]{%
\Xleftrightarrow[#2]{#1}}
%    \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \begin{macro}{\xrightharpoon}
% \begin{macro}{\xleftharpoon}
% \begin{macro}{\xleftrightharpoon}
% This type of arrow behaves as the other ones, except
% that an $\rightharpoonup$ is used at the end 
% of the arrow.
%    \begin{macrocode}
\def\rightharpoonfill@{\arrowfill@\relbar\relbar\rightharpoonup}
\newcommand{\xrightharpoon}[2][]%
{\ext@arrow 0359\rightharpoonfill@{#1}{#2}}
\def\leftharpoonfill@{\arrowfill@\leftharpoonup\relbar\relbar}
\newcommand{\xleftharpoon}[2][]%
{\ext@arrow 3095\leftharpoonfill@{#1}{#2}}
\def\leftrightharpoonfill@%
{\arrowfill@\leftharpoonup\relbar\rightharpoonup}
\newcommand{\xleftrightharpoon}[2][]%
{\ext@arrow 3095\leftrightharpoonfill@{#1}{#2}}
%    \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \begin{macro}{\wkconv}
% \begin{macro}{\leftwkconv}
% \begin{macro}{\leftrightwkconv}
% These macro may be used for the weak convergence.
% Its definition is similar to the one of \verb+\conv+.
%    \begin{macrocode}
\newcommand{\wkconv}{%
\@ifstar{\functan@starred@wkconv}%
{\functan@nonstarred@wkconv}}
\newcommand{\functan@nonstarred@wkconv}[2]{%
\xrightharpoon[#2]{\mempty{#1}}}
\newcommand{\functan@starred@wkconv}[2]{%
\xrightharpoon[#2]{#1}}
\newcommand{\leftwkconv}{%
\@ifstar{\functan@starred@leftwkconv}%
{\functan@nonstarred@leftwkconv}}
\newcommand{\functan@nonstarred@leftwkconv}[2]{%
\xleftharpoon[#2]{\mempty{#1}}}
\newcommand{\functan@starred@leftwkconv}[2]{%
\xleftharpoon[#2]{#1}}
\newcommand{\leftrightwkconv}{%
\@ifstar{\functan@starred@leftrightwkconv}%
{\functan@nonstarred@leftrightwkconv}}
\newcommand{\functan@nonstarred@leftrightwkconv}[2]{%
\xleftrightharpoon[#2]{\mempty{#1}}}
\newcommand{\functan@starred@leftrightwkconv}[2]{%
\xleftrightharpoon[#2]{#1}}
%    \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
% \subsection{Scalar products}
%
% \begin{macro}{\scalprod}
% \begin{macro}{\newscalprod}
% The definition of the scalar product is
% similar to the definition of norms.
%    \begin{macrocode}
\newcommand{\scalprod}{\@ifstar{\functan@starred@scalprod}%
{\functan@nonstarred@scalprod}}
\newcommand{\functan@starred@scalprod}[4][auto]{
\deltwoarg[#1]{#3}{#4}{\langle}%
{\rangle}{,}\@ifempty{#2}{}{_{#2}}}
\newcommand{\functan@nonstarred@scalprod}[4][auto]{
\@ifundefined{functan@scalprod@named@#2}{
\deltwoarg[#1]{#3}{#4}{\langle}%
{\rangle}{,}\@ifempty{#2}{}{_{\m{#2}}}}{%
\@nameuse{functan@scalprod@named@#2}{#1}{#3}{#4}}}
\newcommand{\newscalprod}[1]{%
\@namedef{functan@scalprod@named@#1}##1##2##3}
%</package>
%    \end{macrocode}
% \end{macro}
% \end{macro}
% \Finale
% \setcounter{IndexColumns}{2}
% \PrintIndex