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<h4 class="subsectionHead"><span class="titlemark"><span
class="cmr-12">6.9 </span></span> <a
id="x28-270006.9"></a><span
class="cmr-12">Auxiliary Methods</span></h4>
<!--l. 919--><p class="noindent" ><span
class="cmr-12">Various functionalities are implemented as additional methods of the preconditioner</span>
<span
class="cmr-12">object.</span>
<!--l. 922--><p class="noindent" >
<h5 class="subsubsectionHead"><span class="titlemark"><span
class="cmr-12">6.9.1 </span></span> <a
id="x28-280006.9.1"></a><span
class="cmr-12">Method: dump</span></h5>
<div class="center"
>
<!--l. 924--><p class="noindent" >
<!--l. 925--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">call</span><span
class="cmtt-12"> p%dump(info[,istart,iend,prefix,head,ac,rp,smoother,solver,global_num])</span></span></span><br />
</div>
<!--l. 928--><p class="noindent" ><span
class="cmr-12">Dump on file.</span>
<!--l. 931--><p class="noindent" ><span
class="cmbx-12">Arguments</span>
<div class="tabular"> <table id="TBL-17" class="tabular"
cellspacing="0" cellpadding="0"
><colgroup id="TBL-17-1g"><col
id="TBL-17-1"><col
id="TBL-17-2"></colgroup><tr
style="vertical-align:baseline;" id="TBL-17-1-"><td style="white-space:wrap; text-align:left;" id="TBL-17-1-1"
class="td11"><!--l. 937--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">info</span></span></span> </td><td style="white-space:wrap; text-align:left;" id="TBL-17-1-2"
class="td11"><!--l. 937--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">integer,</span><span
class="cmtt-12"> intent(out)</span></span></span><span
class="cmr-12">.</span> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-17-2-"><td style="white-space:wrap; text-align:left;" id="TBL-17-2-1"
class="td11"><!--l. 938--><p class="noindent" > </td><td style="white-space:wrap; text-align:left;" id="TBL-17-2-2"
class="td11"><!--l. 938--><p class="noindent" ><span
class="cmr-12">Error code. If no error, 0 is returned. See Section</span><span
class="cmr-12"> </span><a
href="userhtmlse8.html#x30-340008"><span
class="cmr-12">8</span><!--tex4ht:ref: sec:errors --></a> <span
class="cmr-12">for details.</span> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-17-3-"><td style="white-space:wrap; text-align:left;" id="TBL-17-3-1"
class="td11"><!--l. 939--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">amold</span></span></span> </td><td style="white-space:wrap; text-align:left;" id="TBL-17-3-2"
class="td11"><!--l. 939--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">class(psb_</span></span></span><span
class="cmti-12">x</span><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">_base_sparse_mat),</span><span
class="cmtt-12"> intent(in),</span><span
class="cmtt-12"> optional</span></span></span><span
class="cmr-12">.</span> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-17-4-"><td style="white-space:wrap; text-align:left;" id="TBL-17-4-1"
class="td11"><!--l. 940--><p class="noindent" > </td><td style="white-space:wrap; text-align:left;" id="TBL-17-4-2"
class="td11"><!--l. 940--><p class="noindent" ><span
class="cmr-12">The desired dynamic type for internal matrix components; this</span>
<span
class="cmr-12">allows e.g. running on GPUs; it needs not be the same on all</span>
<span
class="cmr-12">processes. See the PSBLAS User’s Guide for details </span><span class="cite"><span
class="cmr-12">[</span><a
href="userhtmlli4.html#XPSBLASGUIDE"><span
class="cmr-12">13</span></a><span
class="cmr-12">]</span></span><span
class="cmr-12">.</span> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-17-5-"><td style="white-space:wrap; text-align:left;" id="TBL-17-5-1"
class="td11"> </td> </tr></table></div>
<!--l. 947--><p class="noindent" >
<h5 class="subsubsectionHead"><span class="titlemark"><span
class="cmr-12">6.9.2 </span></span> <a
id="x28-290006.9.2"></a><span
class="cmr-12">Method: clone</span></h5>
<div class="center"
>
<!--l. 949--><p class="noindent" >
<!--l. 950--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">call</span><span
class="cmtt-12"> p%clone(pout,info)</span></span></span><br />
</div>
<!--l. 953--><p class="noindent" ><span
class="cmr-12">Create a (deep) copy of the preconditioner object.</span>
<!--l. 956--><p class="noindent" ><span
class="cmbx-12">Arguments</span>
<div class="tabular"> <table id="TBL-18" class="tabular"
cellspacing="0" cellpadding="0"
><colgroup id="TBL-18-1g"><col
id="TBL-18-1"><col
id="TBL-18-2"></colgroup><tr
style="vertical-align:baseline;" id="TBL-18-1-"><td style="white-space:wrap; text-align:left;" id="TBL-18-1-1"
class="td11"><!--l. 959--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">pout</span></span></span> </td><td style="white-space:wrap; text-align:left;" id="TBL-18-1-2"
class="td11"><!--l. 959--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">type(mld_</span></span></span><span
class="cmti-12">x</span><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">prec_type),</span><span
class="cmtt-12"> intent(out)</span></span></span><span
class="cmr-12">.</span> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-18-2-"><td style="white-space:wrap; text-align:left;" id="TBL-18-2-1"
class="td11"><!--l. 960--><p class="noindent" > </td><td style="white-space:wrap; text-align:left;" id="TBL-18-2-2"
class="td11"><!--l. 960--><p class="noindent" ><span
class="cmr-12">The copy of the preconditioner data structure. Note that </span><span
class="cmti-12">x </span><span
class="cmr-12">must</span>
<span
class="cmr-12">be chosen according to the real/complex, single/double precision</span>
<span
class="cmr-12">version of MLD2P4 under use.</span> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-18-3-"><td style="white-space:wrap; text-align:left;" id="TBL-18-3-1"
class="td11"><!--l. 963--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">info</span></span></span> </td><td style="white-space:wrap; text-align:left;" id="TBL-18-3-2"
class="td11"><!--l. 963--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">integer,</span><span
class="cmtt-12"> intent(out)</span></span></span><span
class="cmr-12">.</span> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-18-4-"><td style="white-space:wrap; text-align:left;" id="TBL-18-4-1"
class="td11"><!--l. 964--><p class="noindent" > </td><td style="white-space:wrap; text-align:left;" id="TBL-18-4-2"
class="td11"><!--l. 964--><p class="noindent" ><span
class="cmr-12">Error code. If no error, 0 is returned. See Section</span><span
class="cmr-12"> </span><a
href="userhtmlse8.html#x30-340008"><span
class="cmr-12">8</span><!--tex4ht:ref: sec:errors --></a> <span
class="cmr-12">for details.</span> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-18-5-"><td style="white-space:wrap; text-align:left;" id="TBL-18-5-1"
class="td11"> </td> </tr></table></div>
<!--l. 969--><p class="noindent" >
<h5 class="subsubsectionHead"><span class="titlemark"><span
class="cmr-12">6.9.3 </span></span> <a
id="x28-300006.9.3"></a><span
class="cmr-12">Method: sizeof</span></h5>
<div class="center"
>
<!--l. 971--><p class="noindent" >
<!--l. 972--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">sz</span><span
class="cmtt-12"> =</span><span
class="cmtt-12"> </span><span
class="cmtt-12"> p%sizeof()</span></span></span><br />
</div>
<!--l. 975--><p class="noindent" ><span
class="cmr-12">Return memory footprint in bytes.</span>
<!--l. 988--><p class="noindent" >
<h5 class="subsubsectionHead"><span class="titlemark"><span
class="cmr-12">6.9.4 </span></span> <a
id="x28-310006.9.4"></a><span
class="cmr-12">Method: allocate</span><span
class="cmr-12">_wrk</span></h5>
<div class="center"
>
<!--l. 990--><p class="noindent" >
<!--l. 991--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">call</span><span
class="cmtt-12"> p%allocate_wrk(info[,</span><span
class="cmtt-12"> vmold])</span></span></span><br />
</div>
<!--l. 994--><p class="noindent" ><span
class="cmr-12">Allocate internal work vectors. Each application of the preconditioner uses a number of</span>
<span
class="cmr-12">work vectors which are allocated internally as necessary; therefore allocation and</span>
<span
class="cmr-12">deallocation of memory occurs multiple times during the execution of a Krylov method.</span>
<span
class="cmr-12">In most cases this strategy is perfectly acceptable, but on some platforms, most</span>
<span
class="cmr-12">notably GPUs, memory allocation is a slow operation, and the default behaviour would</span>
<span
class="cmr-12">lead to a slowdown. This method allows to trade space for time by preallocating</span>
<span
class="cmr-12">the internal workspace outside of the invocation of a Krylov method. When</span>
<span
class="cmr-12">using GPUs or other specialized devices, the </span><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">vmold</span></span></span> <span
class="cmr-12">argument is also necessary</span>
<span
class="cmr-12">to ensure the internal work vectors are of the appropriate dynamic type to</span>
<span
class="cmr-12">exploit the accelerator hardware; when allocation occurs internally this is</span>
<span
class="cmr-12">taken care of based on the dynamic type of the </span><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">x</span></span></span> <span
class="cmr-12">argument to the </span><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">apply</span></span></span>
<span
class="cmr-12">method.</span>
<!--l. 1010--><p class="noindent" ><span
class="cmbx-12">Arguments</span>
<div class="tabular"> <table id="TBL-19" class="tabular"
cellspacing="0" cellpadding="0"
><colgroup id="TBL-19-1g"><col
id="TBL-19-1"><col
id="TBL-19-2"></colgroup><tr
style="vertical-align:baseline;" id="TBL-19-1-"><td style="white-space:wrap; text-align:left;" id="TBL-19-1-1"
class="td11"><!--l. 1016--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">info</span></span></span> </td><td style="white-space:wrap; text-align:left;" id="TBL-19-1-2"
class="td11"><!--l. 1016--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">integer,</span><span
class="cmtt-12"> intent(out)</span></span></span><span
class="cmr-12">.</span> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-19-2-"><td style="white-space:wrap; text-align:left;" id="TBL-19-2-1"
class="td11"><!--l. 1017--><p class="noindent" > </td><td style="white-space:wrap; text-align:left;" id="TBL-19-2-2"
class="td11"><!--l. 1017--><p class="noindent" ><span
class="cmr-12">Error code. If no error, 0 is returned. See Section</span><span
class="cmr-12"> </span><a
href="userhtmlse8.html#x30-340008"><span
class="cmr-12">8</span><!--tex4ht:ref: sec:errors --></a> <span
class="cmr-12">for details.</span> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-19-3-"><td style="white-space:wrap; text-align:left;" id="TBL-19-3-1"
class="td11"><!--l. 1018--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">vmold</span></span></span> </td><td style="white-space:wrap; text-align:left;" id="TBL-19-3-2"
class="td11"><!--l. 1018--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">class(psb_</span></span></span><span
class="cmti-12">x</span><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">_base_vect_type),</span><span
class="cmtt-12"> intent(in),</span><span
class="cmtt-12"> optional</span></span></span><span
class="cmr-12">.</span> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-19-4-"><td style="white-space:wrap; text-align:left;" id="TBL-19-4-1"
class="td11"><!--l. 1019--><p class="noindent" > </td><td style="white-space:wrap; text-align:left;" id="TBL-19-4-2"
class="td11"><!--l. 1019--><p class="noindent" ><span
class="cmr-12">The desired dynamic type for internal vector components; this</span>
<span
class="cmr-12">allows e.g. running on GPUs.</span> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-19-5-"><td style="white-space:wrap; text-align:left;" id="TBL-19-5-1"
class="td11"> </td> </tr></table></div>
<!--l. 1025--><p class="noindent" >
<h5 class="subsubsectionHead"><span class="titlemark"><span
class="cmr-12">6.9.5 </span></span> <a
id="x28-320006.9.5"></a><span
class="cmr-12">Method: free</span><span
class="cmr-12">_wrk</span></h5>
<div class="center"
>
<!--l. 1027--><p class="noindent" >
<!--l. 1028--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">call</span><span
class="cmtt-12"> p%free_wrk(info)</span></span></span><br />
</div>
<!--l. 1031--><p class="noindent" ><span
class="cmr-12">Deallocate internal work vectors.</span>
<!--l. 1034--><p class="noindent" ><span
class="cmbx-12">Arguments</span>
<div class="tabular"> <table id="TBL-20" class="tabular"
cellspacing="0" cellpadding="0"
><colgroup id="TBL-20-1g"><col
id="TBL-20-1"><col
id="TBL-20-2"></colgroup><tr
style="vertical-align:baseline;" id="TBL-20-1-"><td style="white-space:wrap; text-align:left;" id="TBL-20-1-1"
class="td11"><!--l. 1040--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">info</span></span></span> </td><td style="white-space:wrap; text-align:left;" id="TBL-20-1-2"
class="td11"><!--l. 1040--><p class="noindent" ><span class="obeylines-h"><span class="verb"><span
class="cmtt-12">integer,</span><span
class="cmtt-12"> intent(out)</span></span></span><span
class="cmr-12">.</span> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-20-2-"><td style="white-space:wrap; text-align:left;" id="TBL-20-2-1"
class="td11"><!--l. 1041--><p class="noindent" > </td><td style="white-space:wrap; text-align:left;" id="TBL-20-2-2"
class="td11"><!--l. 1041--><p class="noindent" ><span
class="cmr-12">Error code. If no error, 0 is returned. See Section</span><span
class="cmr-12"> </span><a
href="userhtmlse8.html#x30-340008"><span
class="cmr-12">8</span><!--tex4ht:ref: sec:errors --></a> <span
class="cmr-12">for details.</span> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-20-3-"><td style="white-space:wrap; text-align:left;" id="TBL-20-3-1"
class="td11"> </td> </tr></table></div>
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