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Fixed docs.
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+23
-23
@@ -80,25 +80,25 @@ where <!-- MATH
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$A=(a_{ij}) \in \mathbb{R}^{n \times n}$
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-->
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<SPAN CLASS="MATH"><IMG
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WIDTH="137" HEIGHT="37" ALIGN="MIDDLE" BORDER="0"
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WIDTH="137" HEIGHT="38" ALIGN="MIDDLE" BORDER="0"
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SRC="img5.png"
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ALT="$A=(a_{ij}) \in \mathbb{R}^{n \times n}$"></SPAN> is a nonsingular sparse matrix;
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for ease of presentation we assume <SPAN CLASS="MATH"><IMG
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WIDTH="18" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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WIDTH="17" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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SRC="img3.png"
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ALT="$A$"></SPAN> has a symmetric sparsity
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pattern.
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</BIG></BIG></BIG>
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<P>
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<BIG CLASS="LARGE"><BIG CLASS="LARGE"><BIG CLASS="LARGE">Let us consider as finest index space the set of row (column) indices of <SPAN CLASS="MATH"><IMG
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WIDTH="18" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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WIDTH="17" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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SRC="img3.png"
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ALT="$A$"></SPAN>, i.e.,
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<!-- MATH
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$\Omega = \{1, 2, \ldots, n\}$
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-->
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<SPAN CLASS="MATH"><IMG
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WIDTH="131" HEIGHT="34" ALIGN="MIDDLE" BORDER="0"
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WIDTH="132" HEIGHT="36" ALIGN="MIDDLE" BORDER="0"
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SRC="img6.png"
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ALT="$\Omega = \{1, 2, \ldots, n\}$"></SPAN>.
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Any algebraic multilevel preconditioners implemented in MLD2P4 generates
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@@ -122,39 +122,39 @@ a hierarchy of index spaces and a corresponding hierarchy of matrices,
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<BR CLEAR="ALL">
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<P></P><BIG CLASS="LARGE"><BIG CLASS="LARGE"><BIG CLASS="LARGE">
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by using the information contained in <SPAN CLASS="MATH"><IMG
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WIDTH="18" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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WIDTH="17" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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SRC="img3.png"
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ALT="$A$"></SPAN>, without assuming any
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knowledge of the geometry of the problem from which <SPAN CLASS="MATH"><IMG
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WIDTH="18" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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WIDTH="17" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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SRC="img3.png"
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ALT="$A$"></SPAN> originates.
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A vector space <!-- MATH
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$\mathbb{R}^{n_{k}}$
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-->
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<SPAN CLASS="MATH"><IMG
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WIDTH="33" HEIGHT="19" ALIGN="BOTTOM" BORDER="0"
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WIDTH="34" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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SRC="img8.png"
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ALT="$\mathbb{R}^{n_{k}}$"></SPAN> is associated with <SPAN CLASS="MATH"><IMG
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WIDTH="25" HEIGHT="19" ALIGN="BOTTOM" BORDER="0"
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WIDTH="25" HEIGHT="18" ALIGN="BOTTOM" BORDER="0"
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SRC="img9.png"
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ALT="$\Omega^k$"></SPAN>,
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where <SPAN CLASS="MATH"><IMG
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WIDTH="23" HEIGHT="31" ALIGN="MIDDLE" BORDER="0"
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SRC="img10.png"
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ALT="$n_k$"></SPAN> is the size of <SPAN CLASS="MATH"><IMG
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WIDTH="25" HEIGHT="19" ALIGN="BOTTOM" BORDER="0"
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WIDTH="25" HEIGHT="18" ALIGN="BOTTOM" BORDER="0"
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SRC="img9.png"
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ALT="$\Omega^k$"></SPAN>.
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For all <SPAN CLASS="MATH"><IMG
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WIDTH="71" HEIGHT="32" ALIGN="MIDDLE" BORDER="0"
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WIDTH="70" HEIGHT="34" ALIGN="MIDDLE" BORDER="0"
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SRC="img11.png"
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ALT="$k < nlev$"></SPAN>, a restriction operator and a prolongation one are built,
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which connect two levels <SPAN CLASS="MATH"><IMG
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WIDTH="14" HEIGHT="20" ALIGN="BOTTOM" BORDER="0"
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WIDTH="14" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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SRC="img12.png"
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ALT="$k$"></SPAN> and <SPAN CLASS="MATH"><IMG
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WIDTH="44" HEIGHT="32" ALIGN="MIDDLE" BORDER="0"
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WIDTH="44" HEIGHT="34" ALIGN="MIDDLE" BORDER="0"
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SRC="img13.png"
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ALT="$k+1$"></SPAN>:
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</BIG></BIG></BIG>
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@@ -168,7 +168,7 @@ P^k \in \mathbb{R}^{n_k \times n_{k+1}}, \quad
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-->
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<IMG
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WIDTH="255" HEIGHT="30" BORDER="0"
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WIDTH="253" HEIGHT="30" BORDER="0"
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SRC="img14.png"
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ALT="\begin{displaymath}
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P^k \in \mathbb{R}^{n_k \times n_{k+1}}, \quad
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@@ -178,7 +178,7 @@ R^k \in \mathbb{R}^{n_{k+1}\times n_k};
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<BR CLEAR="ALL">
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<P></P><BIG CLASS="LARGE"><BIG CLASS="LARGE"><BIG CLASS="LARGE">
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the matrix <SPAN CLASS="MATH"><IMG
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WIDTH="43" HEIGHT="19" ALIGN="BOTTOM" BORDER="0"
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WIDTH="43" HEIGHT="18" ALIGN="BOTTOM" BORDER="0"
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SRC="img15.png"
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ALT="$A^{k+1}$"></SPAN> is computed by using the previous operators according
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to the Galerkin approach, i.e.,
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@@ -192,7 +192,7 @@ A^{k+1}=R^kA^kP^k.
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-->
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<IMG
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WIDTH="131" HEIGHT="28" BORDER="0"
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WIDTH="129" HEIGHT="27" BORDER="0"
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SRC="img16.png"
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ALT="\begin{displaymath}
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A^{k+1}=R^kA^kP^k.
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@@ -205,22 +205,22 @@ In the current implementation of MLD2P4 we have <SPAN CLASS="MATH"><IMG
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SRC="img17.png"
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ALT="$R^k=(P^k)^T$"></SPAN>
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A smoother with iteration matrix <SPAN CLASS="MATH"><IMG
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WIDTH="31" HEIGHT="19" ALIGN="BOTTOM" BORDER="0"
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WIDTH="32" HEIGHT="18" ALIGN="BOTTOM" BORDER="0"
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SRC="img18.png"
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ALT="$M^k$"></SPAN> is set up at each level <SPAN CLASS="MATH"><IMG
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WIDTH="71" HEIGHT="32" ALIGN="MIDDLE" BORDER="0"
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WIDTH="70" HEIGHT="34" ALIGN="MIDDLE" BORDER="0"
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SRC="img11.png"
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ALT="$k < nlev$"></SPAN>, and a solver
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is set up at the coarsest level, so that they are ready for application
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(for example, setting up a solver based on the <SPAN CLASS="MATH"><IMG
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WIDTH="30" HEIGHT="16" ALIGN="BOTTOM" BORDER="0"
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WIDTH="30" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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SRC="img19.png"
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ALT="$LU$"></SPAN> factorization means computing
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and storing the <SPAN CLASS="MATH"><IMG
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WIDTH="16" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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WIDTH="17" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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SRC="img20.png"
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ALT="$L$"></SPAN> and <SPAN CLASS="MATH"><IMG
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WIDTH="18" HEIGHT="16" ALIGN="BOTTOM" BORDER="0"
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WIDTH="18" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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SRC="img21.png"
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ALT="$U$"></SPAN> factors). The construction of the hierarchy of AMG components
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described so far corresponds to the so-called build phase of the preconditioner.
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@@ -262,8 +262,8 @@ end
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\begin{tabbing}
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\quad \=\quad \=\quad...
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...[1mm]
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\>endif [1mm]
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\>return $u^k$ [1mm]
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\>endif \\ [1mm]
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\>return $u^k$\ \\ [1mm]
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end
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\end{tabbing}\end{minipage}}">
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@@ -276,7 +276,7 @@ end
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to obtain different multilevel preconditioners;
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this is done in the application phase, i.e., in the computation of a vector
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of type <SPAN CLASS="MATH"><IMG
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WIDTH="81" HEIGHT="20" ALIGN="BOTTOM" BORDER="0"
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WIDTH="82" HEIGHT="21" ALIGN="BOTTOM" BORDER="0"
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SRC="img23.png"
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ALT="$w=B^{-1}v$"></SPAN>, where <SPAN CLASS="MATH"><IMG
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WIDTH="19" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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