\batchmode \documentclass[a4paper,twoside,11pt]{article} \usepackage{pstricks} \usepackage{fancybox} \usepackage{amsfonts} \usepackage{ifpdf} \usepackage[bookmarks=true, bookmarksnumbered=true, bookmarksopen=false, plainpages=false, pdfpagelabels, colorlinks, linkcolor=blue]{hyperref} \usepackage{ifthen} \usepackage{graphicx} \newtheorem{theorem}{Theorem} \newtheorem{corollary}{Corollary} \usepackage{rotating} \pdfoutput=0 \setlength \textwidth{1.15\textwidth} \pagestyle{myheadings} \newcounter{subroutine}[subsection] \newcounter{example}[subroutine] \makeatletter% \providecommand{\subsubroutine}[2]{% \stepcounter{subroutine}% \subsection*{\flushleft #1---#2 \endflushleft}% \addcontentsline{toc}{subsubsection}{#1}% \markright{#1}}%% \providecommand{\examplename}{Example}% \providecommand{\syntaxname}{Syntax} \makeatother% \providecommand{\example}{\stepcounter{example}% \section*{Example~\arabic{example}}} % \providecommand{\precdata}{\hyperlink{precdata}{{\tt mld\_prec\_type}}}% \providecommand{\descdata}{\hyperlink{descdata}{{\tt psb\_desc\_type}}}% \providecommand{\spdata}{\hyperlink{spdata}{{\tt psb\_spmat\_type}}}% \providecommand{\Ref}[1]{\mbox{(\ref{#1})}} \usepackage[dvips]{pstcol} \pagecolor[gray]{.7} \usepackage[latin1]{inputenc} \makeatletter \makeatletter \count@=\the\catcode`\_ \catcode`\_=8 \newenvironment{tex2html_wrap}{}{}% \catcode`\<=12\catcode`\_=\count@ \newcommand{\providedcommand}[1]{\expandafter\providecommand\csname #1\endcsname}% \newcommand{\renewedcommand}[1]{\expandafter\providecommand\csname #1\endcsname{}% \expandafter\renewcommand\csname #1\endcsname}% \newcommand{\newedenvironment}[1]{\newenvironment{#1}{}{}\renewenvironment{#1}}% \let\newedcommand\renewedcommand \let\renewedenvironment\newedenvironment \makeatother \let\mathon=$ \let\mathoff=$ \ifx\AtBeginDocument\undefined \newcommand{\AtBeginDocument}[1]{}\fi \newbox\sizebox \setlength{\hoffset}{0pt}\setlength{\voffset}{0pt} \addtolength{\textheight}{\footskip}\setlength{\footskip}{0pt} \addtolength{\textheight}{\topmargin}\setlength{\topmargin}{0pt} \addtolength{\textheight}{\headheight}\setlength{\headheight}{0pt} \addtolength{\textheight}{\headsep}\setlength{\headsep}{0pt} \setlength{\textwidth}{349pt} \newwrite\lthtmlwrite \makeatletter \let\realnormalsize=\normalsize \global\topskip=2sp \def\preveqno{}\let\real@float=\@float \let\realend@float=\end@float \def\@float{\let\@savefreelist\@freelist\real@float} \def\liih@math{\ifmmode$\else\bad@math\fi} \def\end@float{\realend@float\global\let\@freelist\@savefreelist} \let\real@dbflt=\@dbflt \let\end@dblfloat=\end@float \let\@largefloatcheck=\relax \let\if@boxedmulticols=\iftrue \def\@dbflt{\let\@savefreelist\@freelist\real@dbflt} \def\adjustnormalsize{\def\normalsize{\mathsurround=0pt \realnormalsize \parindent=0pt\abovedisplayskip=0pt\belowdisplayskip=0pt}% \def\phantompar{\csname par\endcsname}\normalsize}% \def\lthtmltypeout#1{{\let\protect\string \immediate\write\lthtmlwrite{#1}}}% \newcommand\lthtmlhboxmathA{\adjustnormalsize\setbox\sizebox=\hbox\bgroup\kern.05em }% \newcommand\lthtmlhboxmathB{\adjustnormalsize\setbox\sizebox=\hbox to\hsize\bgroup\hfill }% \newcommand\lthtmlvboxmathA{\adjustnormalsize\setbox\sizebox=\vbox\bgroup % \let\ifinner=\iffalse \let\)\liih@math }% \newcommand\lthtmlboxmathZ{\@next\next\@currlist{}{\def\next{\voidb@x}}% \expandafter\box\next\egroup}% \newcommand\lthtmlmathtype[1]{\gdef\lthtmlmathenv{#1}}% \newcommand\lthtmllogmath{\dimen0\ht\sizebox \advance\dimen0\dp\sizebox \ifdim\dimen0>.95\vsize \lthtmltypeout{% *** image for \lthtmlmathenv\space is too tall at \the\dimen0, reducing to .95 vsize ***}% \ht\sizebox.95\vsize \dp\sizebox\z@ \fi \lthtmltypeout{l2hSize % :\lthtmlmathenv:\the\ht\sizebox::\the\dp\sizebox::\the\wd\sizebox.\preveqno}}% \newcommand\lthtmlfigureA[1]{\let\@savefreelist\@freelist \lthtmlmathtype{#1}\lthtmlvboxmathA}% \newcommand\lthtmlpictureA{\bgroup\catcode`\_=8 \lthtmlpictureB}% \newcommand\lthtmlpictureB[1]{\lthtmlmathtype{#1}\egroup \let\@savefreelist\@freelist \lthtmlhboxmathB}% \newcommand\lthtmlpictureZ[1]{\hfill\lthtmlfigureZ}% \newcommand\lthtmlfigureZ{\lthtmlboxmathZ\lthtmllogmath\copy\sizebox \global\let\@freelist\@savefreelist}% \newcommand\lthtmldisplayA{\bgroup\catcode`\_=8 \lthtmldisplayAi}% \newcommand\lthtmldisplayAi[1]{\lthtmlmathtype{#1}\egroup\lthtmlvboxmathA}% \newcommand\lthtmldisplayB[1]{\edef\preveqno{(\theequation)}% \lthtmldisplayA{#1}\let\@eqnnum\relax}% \newcommand\lthtmldisplayZ{\lthtmlboxmathZ\lthtmllogmath\lthtmlsetmath}% \newcommand\lthtmlinlinemathA{\bgroup\catcode`\_=8 \lthtmlinlinemathB} \newcommand\lthtmlinlinemathB[1]{\lthtmlmathtype{#1}\egroup\lthtmlhboxmathA \vrule height1.5ex width0pt }% \newcommand\lthtmlinlineA{\bgroup\catcode`\_=8 \lthtmlinlineB}% \newcommand\lthtmlinlineB[1]{\lthtmlmathtype{#1}\egroup\lthtmlhboxmathA}% \newcommand\lthtmlinlineZ{\egroup\expandafter\ifdim\dp\sizebox>0pt % \expandafter\centerinlinemath\fi\lthtmllogmath\lthtmlsetinline} \newcommand\lthtmlinlinemathZ{\egroup\expandafter\ifdim\dp\sizebox>0pt % \expandafter\centerinlinemath\fi\lthtmllogmath\lthtmlsetmath} \newcommand\lthtmlindisplaymathZ{\egroup % \centerinlinemath\lthtmllogmath\lthtmlsetmath} \def\lthtmlsetinline{\hbox{\vrule width.1em \vtop{\vbox{% \kern.1em\copy\sizebox}\ifdim\dp\sizebox>0pt\kern.1em\else\kern.3pt\fi \ifdim\hsize>\wd\sizebox \hrule depth1pt\fi}}} \def\lthtmlsetmath{\hbox{\vrule width.1em\kern-.05em\vtop{\vbox{% \kern.1em\kern0.8 pt\hbox{\hglue.17em\copy\sizebox\hglue0.8 pt}}\kern.3pt% \ifdim\dp\sizebox>0pt\kern.1em\fi \kern0.8 pt% \ifdim\hsize>\wd\sizebox \hrule depth1pt\fi}}} \def\centerinlinemath{% \dimen1=\ifdim\ht\sizebox<\dp\sizebox \dp\sizebox\else\ht\sizebox\fi \advance\dimen1by.5pt \vrule width0pt height\dimen1 depth\dimen1 \dp\sizebox=\dimen1\ht\sizebox=\dimen1\relax} \def\lthtmlcheckvsize{\ifdim\ht\sizebox<\vsize \ifdim\wd\sizebox<\hsize\expandafter\hfill\fi \expandafter\vfill \else\expandafter\vss\fi}% \providecommand{\selectlanguage}[1]{}% \makeatletter \tracingstats = 1 \begin{document} \pagestyle{empty}\thispagestyle{empty}\lthtmltypeout{}% \lthtmltypeout{latex2htmlLength hsize=\the\hsize}\lthtmltypeout{}% \lthtmltypeout{latex2htmlLength vsize=\the\vsize}\lthtmltypeout{}% \lthtmltypeout{latex2htmlLength hoffset=\the\hoffset}\lthtmltypeout{}% \lthtmltypeout{latex2htmlLength voffset=\the\voffset}\lthtmltypeout{}% \lthtmltypeout{latex2htmlLength topmargin=\the\topmargin}\lthtmltypeout{}% \lthtmltypeout{latex2htmlLength topskip=\the\topskip}\lthtmltypeout{}% \lthtmltypeout{latex2htmlLength headheight=\the\headheight}\lthtmltypeout{}% \lthtmltypeout{latex2htmlLength headsep=\the\headsep}\lthtmltypeout{}% \lthtmltypeout{latex2htmlLength parskip=\the\parskip}\lthtmltypeout{}% \lthtmltypeout{latex2htmlLength oddsidemargin=\the\oddsidemargin}\lthtmltypeout{}% \makeatletter \if@twoside\lthtmltypeout{latex2htmlLength evensidemargin=\the\evensidemargin}% \else\lthtmltypeout{latex2htmlLength evensidemargin=\the\oddsidemargin}\fi% \lthtmltypeout{}% \makeatother \setcounter{page}{1} \onecolumn % !!! IMAGES START HERE !!! \newlength{\centeroffset}% \begingroup \renewcommand{\thepage}{toc} \endgroup \stepcounter{section} {\newpage\clearpage \lthtmldisplayA{displaymath238}% \begin{displaymath} Ax=b, \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline265}% $A$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} \stepcounter{section} \stepcounter{section} \stepcounter{section} \stepcounter{subsection} \stepcounter{subsection} \stepcounter{subsection} \stepcounter{subsection} \stepcounter{section} \stepcounter{subsection} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline586}% $A=(a_{ij}) \in \Re^{n \times n}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline588}% $G=(W,E)$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline592}% $W=\{1, 2, \ldots, n\}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline594}% $E=\{(i,j) : a_{ij} \neq 0\}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline596}% $G$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline598}% $\delta > 0$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline600}% $\delta$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline602}% $W$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline606}% $m$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline608}% $W_i^0 \subset W$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline610}% $\cup_{i=1}^m W_i^0 = W$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline616}% $W_i^\delta \supset W_i^{\delta-1}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline618}% $W_i^{\delta-1}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline620}% $n_i^\delta$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline622}% $W_i^\delta$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline624}% $R_i^{\delta} \in \Re^{n_i^\delta \times n}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline626}% $v \in \Re^n$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline628}% $v_i^{\delta} \in \Re^{n_i^\delta}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline630}% $v$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline634}% $R_i^{\delta}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline636}% $\Re^{n_i^\delta}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline638}% $\Re^n$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline640}% $A_i^\delta=R_i^\delta A (R_i^\delta)^T \in \Re^{n_i^\delta \times n_i^\delta}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline644}% $W_i^{\delta}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmldisplayA{displaymath564}% \begin{displaymath} M_{AS}^{-1}= \sum_{i=1}^m (R_i^{\delta})^T (A_i^\delta)^{-1} R_i^{\delta}, \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline646}% $A_i^\delta$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline652}% $v_i = R_i^{\delta} v$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline654}% $i=1,\ldots,m$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline656}% $A_i^\delta w_i = v_i$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline660}% $w_i$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline662}% $w = \sum_{i=1}^m (R_i^{\delta})^T w_i$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline664}% $p$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline668}% $p,t$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline672}% $(\tilde{R}_i^0)^T \in \Re^{n_i^\delta \times n}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline674}% $\tilde{R}_i^0$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline676}% $R_i^\delta$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline678}% $W_i^\delta \backslash W_i^0$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmldisplayA{displaymath565}% \begin{displaymath} M_{RAS}^{-1}= \sum_{i=1}^m (\tilde{R}_i^0)^T (A_i^\delta)^{-1} R_i^{\delta}. \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmldisplayA{displaymath566}% \begin{displaymath} M_{ASH}^{-1}= \sum_{i=1}^m (R_i^{\delta})^T (A_i^\delta)^{-1} \tilde{R}_i^0. \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline680}% $\delta=0$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline686}% $A_C$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline692}% $W_C$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline694}% $n_C$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline696}% $R_C \in \Re^{n_C \times n}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmldisplayA{displaymath567}% \begin{displaymath} A_C=R_C A R_C^T \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline700}% $M_{1L}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmldisplayA{displaymath568}% \begin{displaymath} M_{C}^{-1}= R_C^T A_C^{-1} R_C, \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline704}% $M_{C}^{-1}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline710}% $M_{C}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmldisplayA{displaymath569}% \begin{displaymath} M_{2LA}^{-1} = M_{C}^{-1} + M_{1L}^{-1}. \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline714}% $M_{2L-A}^{-1}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline720}% $M_{1L}^{-1}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmldisplayA{displaymath570}% \begin{displaymath} \begin{array}{l} w = M_{1L}^{-1} v, \\ z = w + M_{C}^{-1} (v-Aw); \end{array} \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmldisplayA{displaymath571}% \begin{displaymath} M_{2LH-PRE}^{-1} = M_{C}^{-1} + \left( I - M_{C}^{-1}A \right) M_{1L}^{-1}. \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmldisplayA{displaymath572}% \begin{displaymath} \begin{array}{l} w = M_{C}^{-1} v , \\ z = w + M_{1L}^{-1} (v-Aw) , \end{array} \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmldisplayA{displaymath573}% \begin{displaymath} M_{2LH-POST}^{-1} = M_{1L}^{-1} + \left( I - M_{1L}^{-1}A \right) M_{C}^{-1}. \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline734}% $M$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline738}% $w=M^{-1}v$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline740}% $nlev$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline742}% $l$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline744}% $A_l$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline746}% $M_l$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline748}% $A_1=A$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlpictureA{tex2html_wrap860}% \framebox{ \begin{minipage}{.85\textwidth} {\small \begin{tabbing} \quad \=\quad \=\quad \=\quad \\[-1mm] $v_1 = v$; \\[2mm] \textbf{for $l=2, nlev$\ do}\\[1mm] \> ! transfer $v_{l-1}$\ to the next coarser level\\ \> $v_l = R_lv_{l-1}$\ \\[1mm] \textbf{endfor} \\[2mm] ! apply the coarsest-level correction\\[1mm] $y_{nlev} = A_{nlev}^{-1} v_{nlev}$\\[2mm] \textbf{for $l=nlev -1 , 1, -1$\ do}\\[1mm] \> ! transfer $y_{l+1}$\ to the next finer level\\ \> $y_l = R_{l+1}^T y_{l+1}$;\\[1mm] \> ! compute the residual at the current level\\ \> $r_l = v_l-A_l^{-1} y_l$;\\[1mm] \> ! apply the basic Schwarz preconditioner to the residual\\ \> $r_l = M_l^{-1} r_l$\\[1mm] \> ! update $y_l$\\ \> $y_l = y_l+r_l$\\ \textbf{endfor} \\[1mm] $w = y_1$; \end{tabbing} } \end{minipage} }% \lthtmlpictureZ \lthtmlcheckvsize\clearpage} \stepcounter{subsection} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline776}% $R_C$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline784}% $R_C^T$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline798}% $N_r$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline802}% $r \in W$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmldisplayA{displaymath574}% \begin{displaymath} N_r = \left\{s \in W: |a_{rs}| > \theta \sqrt{|a_{rr}a_{ss}|} \right\} \cup \left\{ r \right\} , \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline804}% $\theta \in [0,1]$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline806}% $i$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline808}% $W_i^0$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline812}% $P_C=R_C^T$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline814}% $P \in \Re^{n \times n_C}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmldisplayA{displaymath531}% \begin{displaymath} P=(p_{ij}), \quad p_{ij}= \left\{ \begin{array}{ll} 1 & \quad \mbox{if} \; i \in V^j_C \\ 0 & \quad \mbox{otherwise} \end{array} \right. . \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline816}% $P_C$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline818}% $P$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline820}% $S \in \Re^{n \times n}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmldisplayA{displaymath542}% \begin{displaymath} P_C = S P, \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline822}% $S$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmldisplayA{displaymath546}% \begin{displaymath} S = I - \omega D^{-1} A , \end{displaymath}% \lthtmldisplayZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline824}% $\omega$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline826}% $D^{-1}A$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} \stepcounter{section} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline983}% $\theta = 0$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} \stepcounter{subsection} \stepcounter{section} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline1324}% $w$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} \stepcounter{subsection} \stepcounter{subsection} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline1328}% $\ge 0$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline1342}% $t$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline1346}% $\in [0, 1]$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline1348}% $\theta$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline1352}% $>0$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} \stepcounter{subsection} \stepcounter{subsection} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline1374}% $y = op(M^{-1})\, x$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline1378}% $op$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline1382}% $x$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline1384}% $y$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline1386}% $op(M^{-1}) = M^{-1}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline1388}% $op(M^{-1}) = M^{-T}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline1390}% $M^{-1})$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} {\newpage\clearpage \lthtmlinlinemathA{tex2html_wrap_inline1392}% $op(M^{-1}) = M^{-C}$% \lthtmlinlinemathZ \lthtmlcheckvsize\clearpage} \stepcounter{subsection} \stepcounter{subsection} \stepcounter{section} \appendix \stepcounter{section} \end{document}