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Merged MixedI8 in new branch (to be later merged into development)
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@@ -61,7 +61,7 @@ space to which there corresponds an index space and a matrix sparsity
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pattern. As an example, consider a cell-centered finite-volume
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discretization of the Navier-Stokes equations on a simulation domain;
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the index space <SPAN CLASS="MATH"><IMG
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WIDTH="46" HEIGHT="13" ALIGN="BOTTOM" BORDER="0"
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WIDTH="45" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
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SRC="img15.png"
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ALT="$1\dots n$"></SPAN> is isomorphic to the set of cell centers,
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whereas the pattern of the associated linear system matrix is
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@@ -72,7 +72,7 @@ by the discretization stencil.
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Thus the first order of business is to establish an index space, and
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this is done with a call to <code>psb_cdall</code> in which we specify the
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size of the index space <SPAN CLASS="MATH"><IMG
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WIDTH="13" HEIGHT="13" ALIGN="BOTTOM" BORDER="0"
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WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
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SRC="img16.png"
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ALT="$n$"></SPAN> and the allocation of the elements of the
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index space to the various processes making up the MPI (virtual)
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@@ -81,22 +81,22 @@ parallel machine.
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<P>
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The index space is partitioned among processes, and this creates a
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mapping from the “global” numbering <SPAN CLASS="MATH"><IMG
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WIDTH="46" HEIGHT="13" ALIGN="BOTTOM" BORDER="0"
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WIDTH="45" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
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SRC="img15.png"
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ALT="$1\dots n$"></SPAN> to a numbering
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“local” to each process; each process <SPAN CLASS="MATH"><IMG
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WIDTH="9" HEIGHT="17" ALIGN="BOTTOM" BORDER="0"
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WIDTH="9" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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SRC="img4.png"
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ALT="$i$"></SPAN> will own a certain subset
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<!-- MATH
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$1\dots n_{\hbox{row}_i}$
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-->
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<SPAN CLASS="MATH"><IMG
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WIDTH="77" HEIGHT="30" ALIGN="MIDDLE" BORDER="0"
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WIDTH="76" HEIGHT="29" ALIGN="MIDDLE" BORDER="0"
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SRC="img17.png"
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ALT="$1\dots n_{\hbox{row}_i}$"></SPAN>, each element of which corresponds to a certain
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element of <SPAN CLASS="MATH"><IMG
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WIDTH="46" HEIGHT="13" ALIGN="BOTTOM" BORDER="0"
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WIDTH="45" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
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SRC="img15.png"
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ALT="$1\dots n$"></SPAN>. The user does not set explicitly this mapping;
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when the application needs to indicate to which element of the index
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@@ -106,7 +106,7 @@ library will translate into the appropriate “local” numbering.
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<P>
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For a given index space <SPAN CLASS="MATH"><IMG
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WIDTH="46" HEIGHT="13" ALIGN="BOTTOM" BORDER="0"
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WIDTH="45" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
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SRC="img15.png"
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ALT="$1\dots n$"></SPAN> there are many possible associated
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topologies, i.e. many different discretization stencils; thus the
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@@ -115,7 +115,7 @@ defined a sparsity pattern, either explicitly through <code>psb_cdins</code>
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or implicitly through <code>psb_spins</code>. The descriptor is finalized
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with a call to <code>psb_cdasb</code> and a sparse matrix with a call to
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<code>psb_spasb</code>. After <code>psb_cdasb</code> each process <SPAN CLASS="MATH"><IMG
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WIDTH="9" HEIGHT="17" ALIGN="BOTTOM" BORDER="0"
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WIDTH="9" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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SRC="img4.png"
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ALT="$i$"></SPAN> will have
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defined a set of “halo” (or “ghost”) indices
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@@ -123,16 +123,16 @@ defined a set of “halo” (or “ghost”) indices
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$n_{\hbox{row}_i}+1\dots n_{\hbox{col}_i}$
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-->
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<SPAN CLASS="MATH"><IMG
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WIDTH="130" HEIGHT="30" ALIGN="MIDDLE" BORDER="0"
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WIDTH="131" HEIGHT="29" ALIGN="MIDDLE" BORDER="0"
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SRC="img18.png"
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ALT="$n_{\hbox{row}_i}+1\dots n_{\hbox{col}_i}$"></SPAN>, denoting elements of the index
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space that are <SPAN CLASS="textit">not</SPAN> assigned to process <SPAN CLASS="MATH"><IMG
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WIDTH="9" HEIGHT="17" ALIGN="BOTTOM" BORDER="0"
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WIDTH="9" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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SRC="img4.png"
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ALT="$i$"></SPAN>; however the
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variables associated with them are needed to complete computations
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associated with the sparse matrix <SPAN CLASS="MATH"><IMG
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WIDTH="16" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
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WIDTH="16" HEIGHT="15" ALIGN="BOTTOM" BORDER="0"
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SRC="img1.png"
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ALT="$A$"></SPAN>, and thus they have to be
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fetched from (neighbouring) processes. The descriptor of the index
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@@ -173,8 +173,8 @@ follows:
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<LI>Call the iterative method of choice, e.g. <code>psb_bicgstab</code>
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</LI>
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</OL>
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This is the structure of the sample program
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<code>test/pargen/psb_d_pde3d.f90</code>.
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This is the structure of the sample programs in the directory
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<code>test/pargen/</code>.
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<P>
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For a simulation in which the same discretization mesh is used over
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