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<center><a href="jacobi.c">Actual source code: jacobi.c</a></center><br>
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<pre width="80"><a name="line1"> 1: </a><font color="#B22222">/*$Id: jacobi.c,v 1.75 2001/08/07 03:03:32 balay Exp $*/</font>
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<a name="line3"> 3: </a><font color="#B22222">/* -------------------------------------------------------------------- </font>
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<a name="line5"> 5: </a><font color="#B22222"> This file implements a Jacobi preconditioner for matrices that use</font>
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<a name="line6"> 6: </a><font color="#B22222"> the <A href="../../../../../docs/manualpages/Mat/Mat.html#Mat">Mat</A> interface (various matrix formats). Actually, the only</font>
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<a name="line7"> 7: </a><font color="#B22222"> matrix operation used here is <A href="../../../../../docs/manualpages/Mat/MatGetDiagonal.html#MatGetDiagonal">MatGetDiagonal</A>(), which extracts </font>
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<a name="line8"> 8: </a><font color="#B22222"> diagonal elements of the preconditioning matrix.</font>
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<a name="line10"> 10: </a><font color="#B22222"> The following basic routines are required for each preconditioner.</font>
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<a name="line11"> 11: </a><font color="#B22222"> PCCreate_XXX() - Creates a preconditioner context</font>
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<a name="line12"> 12: </a><font color="#B22222"> PCSetFromOptions_XXX() - Sets runtime options</font>
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<a name="line13"> 13: </a><font color="#B22222"> PCApply_XXX() - Applies the preconditioner</font>
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<a name="line14"> 14: </a><font color="#B22222"> PCDestroy_XXX() - Destroys the preconditioner context</font>
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<a name="line15"> 15: </a><font color="#B22222"> where the suffix "_XXX" denotes a particular implementation, in</font>
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<a name="line16"> 16: </a><font color="#B22222"> this case we use _Jacobi (e.g., PCCreate_Jacobi, PCApply_Jacobi).</font>
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<a name="line17"> 17: </a><font color="#B22222"> These routines are actually called via the common user interface</font>
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<a name="line18"> 18: </a><font color="#B22222"> routines <A href="../../../../../docs/manualpages/PC/PCCreate.html#PCCreate">PCCreate</A>(), <A href="../../../../../docs/manualpages/PC/PCSetFromOptions.html#PCSetFromOptions">PCSetFromOptions</A>(), <A href="../../../../../docs/manualpages/PC/PCApply.html#PCApply">PCApply</A>(), and <A href="../../../../../docs/manualpages/PC/PCDestroy.html#PCDestroy">PCDestroy</A>(), </font>
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<a name="line19"> 19: </a><font color="#B22222"> so the application code interface remains identical for all </font>
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<a name="line20"> 20: </a><font color="#B22222"> preconditioners. </font>
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<a name="line22"> 22: </a><font color="#B22222"> Another key routine is:</font>
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<a name="line23"> 23: </a><font color="#B22222"> PCSetUp_XXX() - Prepares for the use of a preconditioner</font>
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<a name="line24"> 24: </a><font color="#B22222"> by setting data structures and options. The interface routine <A href="../../../../../docs/manualpages/PC/PCSetUp.html#PCSetUp">PCSetUp</A>()</font>
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<a name="line25"> 25: </a><font color="#B22222"> is not usually called directly by the user, but instead is called by</font>
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<a name="line26"> 26: </a><font color="#B22222"> <A href="../../../../../docs/manualpages/PC/PCApply.html#PCApply">PCApply</A>() if necessary.</font>
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<a name="line28"> 28: </a><font color="#B22222"> Additional basic routines are:</font>
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<a name="line29"> 29: </a><font color="#B22222"> PCView_XXX() - Prints details of runtime options that</font>
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<a name="line30"> 30: </a><font color="#B22222"> have actually been used.</font>
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<a name="line31"> 31: </a><font color="#B22222"> These are called by application codes via the interface routines</font>
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<a name="line32"> 32: </a><font color="#B22222"> <A href="../../../../../docs/manualpages/PC/PCView.html#PCView">PCView</A>().</font>
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<a name="line34"> 34: </a><font color="#B22222"> The various types of solvers (preconditioners, Krylov subspace methods,</font>
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<a name="line35"> 35: </a><font color="#B22222"> nonlinear solvers, timesteppers) are all organized similarly, so the</font>
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<a name="line36"> 36: </a><font color="#B22222"> above description applies to these categories also. One exception is</font>
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<a name="line37"> 37: </a><font color="#B22222"> that the analogues of <A href="../../../../../docs/manualpages/PC/PCApply.html#PCApply">PCApply</A>() for these components are <A href="../../../../../docs/manualpages/KSP/KSPSolve.html#KSPSolve">KSPSolve</A>(), </font>
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<a name="line38"> 38: </a><font color="#B22222"> <A href="../../../../../docs/manualpages/SNES/SNESSolve.html#SNESSolve">SNESSolve</A>(), and TSSolve().</font>
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<a name="line40"> 40: </a><font color="#B22222"> Additional optional functionality unique to preconditioners is left and</font>
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<a name="line41"> 41: </a><font color="#B22222"> right symmetric preconditioner application via <A href="../../../../../docs/manualpages/PC/PCApplySymmetricLeft.html#PCApplySymmetricLeft">PCApplySymmetricLeft</A>() </font>
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<a name="line42"> 42: </a><font color="#B22222"> and <A href="../../../../../docs/manualpages/PC/PCApplySymmetricRight.html#PCApplySymmetricRight">PCApplySymmetricRight</A>(). The Jacobi implementation is </font>
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<a name="line43"> 43: </a><font color="#B22222"> PCApplySymmetricLeftOrRight_Jacobi().</font>
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<a name="line45"> 45: </a><font color="#B22222"> -------------------------------------------------------------------- */</font>
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<a name="line47"> 47: </a><font color="#B22222">/* </font>
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<a name="line48"> 48: </a><font color="#B22222"> Include files needed for the Jacobi preconditioner:</font>
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<a name="line49"> 49: </a><font color="#B22222"> pcimpl.h - private include file intended for use by all preconditioners </font>
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<a name="line50"> 50: </a><font color="#B22222">*/</font>
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<a name="line52"> 52: </a> #include <A href="../../../../../src/sles/pc/pcimpl.h.html">src/sles/pc/pcimpl.h</A>
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<a name="line54"> 54: </a><font color="#B22222">/* </font>
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<a name="line55"> 55: </a><font color="#B22222"> Private context (data structure) for the Jacobi preconditioner. </font>
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<a name="line56"> 56: </a><font color="#B22222">*/</font>
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<a name="line57"> 57: </a><font color="#4169E1">typedef</font> <font color="#4169E1">struct</font> {
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<a name="line58"> 58: </a> <A href="../../../../../docs/manualpages/Vec/Vec.html#Vec">Vec</A> diag; <font color="#B22222">/* vector containing the reciprocals of the diagonal elements</font>
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<a name="line59"> 59: </a><font color="#B22222"> of the preconditioner matrix */</font>
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<a name="line60"> 60: </a> <A href="../../../../../docs/manualpages/Vec/Vec.html#Vec">Vec</A> diagsqrt; <font color="#B22222">/* vector containing the reciprocals of the square roots of</font>
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<a name="line61"> 61: </a><font color="#B22222"> the diagonal elements of the preconditioner matrix (used </font>
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<a name="line62"> 62: </a><font color="#B22222"> only for symmetric preconditioner application) */</font>
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<a name="line63"> 63: </a> <A href="../../../../../docs/manualpages/Sys/PetscTruth.html#PetscTruth">PetscTruth</A> userowmax;
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<a name="line64"> 64: </a>} PC_Jacobi;
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<a name="line66"> 66: </a><strong><font color="#4169E1"><a name="PCJacobiSetUseRowMax_Jacobi"></a>EXTERN_C_BEGIN</font></strong>
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<a name="line67"> 67: </a><strong><font color="#4169E1">int PCJacobiSetUseRowMax_Jacobi(<A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A> pc)</font></strong>
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<a name="line68"> 68: </a>{
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<a name="line69"> 69: </a> PC_Jacobi *j;
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<a name="line72"> 72: </a> j = (PC_Jacobi*)pc->data;
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<a name="line73"> 73: </a> j->userowmax = PETSC_TRUE;
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<a name="line74"> 74: </a> <font color="#4169E1">return</font>(0);
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<a name="line75"> 75: </a>}
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<a name="line76"> 76: </a>EXTERN_C_END
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<a name="line78"> 78: </a><font color="#B22222">/* -------------------------------------------------------------------------- */</font>
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<a name="line79"> 79: </a><font color="#B22222">/*</font>
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<a name="line80"> 80: </a><font color="#B22222"> PCSetUp_Jacobi - Prepares for the use of the Jacobi preconditioner</font>
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<a name="line81"> 81: </a><font color="#B22222"> by setting data structures and options. </font>
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<a name="line83"> 83: </a><font color="#B22222"> Input Parameter:</font>
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<a name="line84"> 84: </a><font color="#B22222">. pc - the preconditioner context</font>
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<a name="line86"> 86: </a><font color="#B22222"> Application Interface Routine: <A href="../../../../../docs/manualpages/PC/PCSetUp.html#PCSetUp">PCSetUp</A>()</font>
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<a name="line88"> 88: </a><font color="#B22222"> Notes:</font>
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<a name="line89"> 89: </a><font color="#B22222"> The interface routine <A href="../../../../../docs/manualpages/PC/PCSetUp.html#PCSetUp">PCSetUp</A>() is not usually called directly by</font>
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<a name="line90"> 90: </a><font color="#B22222"> the user, but instead is called by <A href="../../../../../docs/manualpages/PC/PCApply.html#PCApply">PCApply</A>() if necessary.</font>
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<a name="line91"> 91: </a><font color="#B22222">*/</font>
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<a name="line92"> 92: </a><strong><font color="#4169E1"><a name="PCSetUp_Jacobi"></a>static int PCSetUp_Jacobi(<A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A> pc)</font></strong>
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<a name="line93"> 93: </a>{
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<a name="line94"> 94: </a> PC_Jacobi *jac = (PC_Jacobi*)pc->data;
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<a name="line95"> 95: </a> <A href="../../../../../docs/manualpages/Vec/Vec.html#Vec">Vec</A> diag,diagsqrt;
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<a name="line96"> 96: </a> int ierr,n,i,zeroflag=0;
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<a name="line97"> 97: </a> <A href="../../../../../docs/manualpages/Sys/PetscScalar.html#PetscScalar">PetscScalar</A> *x;
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<a name="line101">101: </a> <font color="#B22222">/*</font>
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<a name="line102">102: </a><font color="#B22222"> For most preconditioners the code would begin here something like</font>
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<a name="line104">104: </a><font color="#B22222"> if (pc->setupcalled == 0) { allocate space the first time this is ever called</font>
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<a name="line105">105: </a><font color="#B22222"> <A href="../../../../../docs/manualpages/Vec/VecDuplicate.html#VecDuplicate">VecDuplicate</A>(pc->vec,&jac->diag);</font>
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<a name="line106">106: </a><font color="#B22222"> PetscLogObjectParent(pc,jac->diag);</font>
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<a name="line107">107: </a><font color="#B22222"> }</font>
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<a name="line109">109: </a><font color="#B22222"> But for this preconditioner we want to support use of both the matrix' diagonal</font>
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<a name="line110">110: </a><font color="#B22222"> elements (for left or right preconditioning) and square root of diagonal elements</font>
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<a name="line111">111: </a><font color="#B22222"> (for symmetric preconditioning). Hence we do not allocate space here, since we</font>
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<a name="line112">112: </a><font color="#B22222"> don't know at this point which will be needed (diag and/or diagsqrt) until the user</font>
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<a name="line113">113: </a><font color="#B22222"> applies the preconditioner, and we don't want to allocate BOTH unless we need</font>
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<a name="line114">114: </a><font color="#B22222"> them both. Thus, the diag and diagsqrt are allocated in PCSetUp_Jacobi_NonSymmetric()</font>
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<a name="line115">115: </a><font color="#B22222"> and PCSetUp_Jacobi_Symmetric(), respectively.</font>
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<a name="line116">116: </a><font color="#B22222"> */</font>
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<a name="line118">118: </a> <font color="#B22222">/*</font>
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<a name="line119">119: </a><font color="#B22222"> Here we set up the preconditioner; that is, we copy the diagonal values from</font>
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<a name="line120">120: </a><font color="#B22222"> the matrix and put them into a format to make them quick to apply as a preconditioner.</font>
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<a name="line121">121: </a><font color="#B22222"> */</font>
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<a name="line122">122: </a> diag = jac->diag;
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<a name="line123">123: </a> diagsqrt = jac->diagsqrt;
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<a name="line125">125: </a> <font color="#4169E1">if</font> (diag) {
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<a name="line126">126: </a> <font color="#4169E1">if</font> (jac->userowmax) {
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<a name="line127">127: </a> <A href="../../../../../docs/manualpages/Mat/MatGetRowMax.html#MatGetRowMax">MatGetRowMax</A>(pc->pmat,diag);
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<a name="line128">128: </a> } <font color="#4169E1">else</font> {
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<a name="line129">129: </a> <A href="../../../../../docs/manualpages/Mat/MatGetDiagonal.html#MatGetDiagonal">MatGetDiagonal</A>(pc->pmat,diag);
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<a name="line130">130: </a> }
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<a name="line131">131: </a> <A href="../../../../../docs/manualpages/Vec/VecReciprocal.html#VecReciprocal">VecReciprocal</A>(diag);
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<a name="line132">132: </a> <A href="../../../../../docs/manualpages/Vec/VecGetLocalSize.html#VecGetLocalSize">VecGetLocalSize</A>(diag,&n);
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<a name="line133">133: </a> <A href="../../../../../docs/manualpages/Vec/VecGetArray.html#VecGetArray">VecGetArray</A>(diag,&x);
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<a name="line134">134: </a> <font color="#4169E1">for</font> (i=0; i<n; i++) {
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<a name="line135">135: </a> <font color="#4169E1">if</font> (x[i] == 0.0) {
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<a name="line136">136: </a> x[i] = 1.0;
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<a name="line137">137: </a> zeroflag = 1;
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<a name="line138">138: </a> }
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<a name="line139">139: </a> }
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<a name="line140">140: </a> <A href="../../../../../docs/manualpages/Vec/VecRestoreArray.html#VecRestoreArray">VecRestoreArray</A>(diag,&x);
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<a name="line141">141: </a> }
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<a name="line142">142: </a> <font color="#4169E1">if</font> (diagsqrt) {
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<a name="line143">143: </a> <font color="#4169E1">if</font> (jac->userowmax) {
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<a name="line144">144: </a> <A href="../../../../../docs/manualpages/Mat/MatGetRowMax.html#MatGetRowMax">MatGetRowMax</A>(pc->pmat,diagsqrt);
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<a name="line145">145: </a> } <font color="#4169E1">else</font> {
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<a name="line146">146: </a> <A href="../../../../../docs/manualpages/Mat/MatGetDiagonal.html#MatGetDiagonal">MatGetDiagonal</A>(pc->pmat,diagsqrt);
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<a name="line147">147: </a> }
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<a name="line148">148: </a> <A href="../../../../../docs/manualpages/Vec/VecGetLocalSize.html#VecGetLocalSize">VecGetLocalSize</A>(diagsqrt,&n);
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<a name="line149">149: </a> <A href="../../../../../docs/manualpages/Vec/VecGetArray.html#VecGetArray">VecGetArray</A>(diagsqrt,&x);
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<a name="line150">150: </a> <font color="#4169E1">for</font> (i=0; i<n; i++) {
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<a name="line151">151: </a> <font color="#4169E1">if</font> (x[i] != 0.0) x[i] = 1.0/sqrt(PetscAbsScalar(x[i]));
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<a name="line152">152: </a> <font color="#4169E1">else</font> {
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<a name="line153">153: </a> x[i] = 1.0;
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<a name="line154">154: </a> zeroflag = 1;
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<a name="line155">155: </a> }
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<a name="line156">156: </a> }
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<a name="line157">157: </a> <A href="../../../../../docs/manualpages/Vec/VecRestoreArray.html#VecRestoreArray">VecRestoreArray</A>(diagsqrt,&x);
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<a name="line158">158: </a> }
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<a name="line159">159: </a> <font color="#4169E1">if</font> (zeroflag) {
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<a name="line160">160: </a> <A href="../../../../../docs/manualpages/Profiling/PetscLogInfo.html#PetscLogInfo">PetscLogInfo</A>(pc,<font color="#666666">"PCSetUp_Jacobi:Zero detected in diagonal of matrix, using 1 at those locationsn"</font>);
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<a name="line161">161: </a> }
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<a name="line163">163: </a> <font color="#4169E1">return</font>(0);
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<a name="line164">164: </a>}
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<a name="line165">165: </a><font color="#B22222">/* -------------------------------------------------------------------------- */</font>
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<a name="line166">166: </a><font color="#B22222">/*</font>
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<a name="line167">167: </a><font color="#B22222"> PCSetUp_Jacobi_Symmetric - Allocates the vector needed to store the</font>
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<a name="line168">168: </a><font color="#B22222"> inverse of the square root of the diagonal entries of the matrix. This</font>
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<a name="line169">169: </a><font color="#B22222"> is used for symmetric application of the Jacobi preconditioner.</font>
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<a name="line171">171: </a><font color="#B22222"> Input Parameter:</font>
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<a name="line172">172: </a><font color="#B22222">. pc - the preconditioner context</font>
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<a name="line173">173: </a><font color="#B22222">*/</font>
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<a name="line174">174: </a><strong><font color="#4169E1"><a name="PCSetUp_Jacobi_Symmetric"></a>static int PCSetUp_Jacobi_Symmetric(<A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A> pc)</font></strong>
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<a name="line175">175: </a>{
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<a name="line176">176: </a> int ierr;
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<a name="line177">177: </a> PC_Jacobi *jac = (PC_Jacobi*)pc->data;
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<a name="line181">181: </a> <A href="../../../../../docs/manualpages/Vec/VecDuplicate.html#VecDuplicate">VecDuplicate</A>(pc->vec,&jac->diagsqrt);
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<a name="line182">182: </a> PetscLogObjectParent(pc,jac->diagsqrt);
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<a name="line183">183: </a> PCSetUp_Jacobi(pc);
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<a name="line184">184: </a> <font color="#4169E1">return</font>(0);
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<a name="line185">185: </a>}
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<a name="line186">186: </a><font color="#B22222">/* -------------------------------------------------------------------------- */</font>
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<a name="line187">187: </a><font color="#B22222">/*</font>
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<a name="line188">188: </a><font color="#B22222"> PCSetUp_Jacobi_NonSymmetric - Allocates the vector needed to store the</font>
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<a name="line189">189: </a><font color="#B22222"> inverse of the diagonal entries of the matrix. This is used for left of</font>
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<a name="line190">190: </a><font color="#B22222"> right application of the Jacobi preconditioner.</font>
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<a name="line192">192: </a><font color="#B22222"> Input Parameter:</font>
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<a name="line193">193: </a><font color="#B22222">. pc - the preconditioner context</font>
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<a name="line194">194: </a><font color="#B22222">*/</font>
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<a name="line195">195: </a><strong><font color="#4169E1"><a name="PCSetUp_Jacobi_NonSymmetric"></a>static int PCSetUp_Jacobi_NonSymmetric(<A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A> pc)</font></strong>
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<a name="line196">196: </a>{
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<a name="line197">197: </a> int ierr;
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<a name="line198">198: </a> PC_Jacobi *jac = (PC_Jacobi*)pc->data;
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<a name="line202">202: </a> <A href="../../../../../docs/manualpages/Vec/VecDuplicate.html#VecDuplicate">VecDuplicate</A>(pc->vec,&jac->diag);
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<a name="line203">203: </a> PetscLogObjectParent(pc,jac->diag);
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<a name="line204">204: </a> PCSetUp_Jacobi(pc);
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<a name="line205">205: </a> <font color="#4169E1">return</font>(0);
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<a name="line206">206: </a>}
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<a name="line207">207: </a><font color="#B22222">/* -------------------------------------------------------------------------- */</font>
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<a name="line208">208: </a><font color="#B22222">/*</font>
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<a name="line209">209: </a><font color="#B22222"> PCApply_Jacobi - Applies the Jacobi preconditioner to a vector.</font>
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<a name="line211">211: </a><font color="#B22222"> Input Parameters:</font>
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<a name="line212">212: </a><font color="#B22222">. pc - the preconditioner context</font>
219
<a name="line213">213: </a><font color="#B22222">. x - input vector</font>
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<a name="line215">215: </a><font color="#B22222"> Output Parameter:</font>
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<a name="line216">216: </a><font color="#B22222">. y - output vector</font>
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<a name="line218">218: </a><font color="#B22222"> Application Interface Routine: <A href="../../../../../docs/manualpages/PC/PCApply.html#PCApply">PCApply</A>()</font>
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<a name="line219">219: </a><font color="#B22222"> */</font>
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<a name="line220">220: </a><strong><font color="#4169E1"><a name="PCApply_Jacobi"></a>static int PCApply_Jacobi(<A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A> pc,<A href="../../../../../docs/manualpages/Vec/Vec.html#Vec">Vec</A> x,<A href="../../../../../docs/manualpages/Vec/Vec.html#Vec">Vec</A> y)</font></strong>
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<a name="line221">221: </a>{
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<a name="line222">222: </a> PC_Jacobi *jac = (PC_Jacobi*)pc->data;
229
<a name="line223">223: </a> int ierr;
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<a name="line226">226: </a> <font color="#4169E1">if</font> (!jac->diag) {
232
<a name="line227">227: </a> PCSetUp_Jacobi_NonSymmetric(pc);
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<a name="line228">228: </a> }
234
<a name="line229">229: </a> <A href="../../../../../docs/manualpages/Vec/VecPointwiseMult.html#VecPointwiseMult">VecPointwiseMult</A>(x,jac->diag,y);
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<a name="line230">230: </a> <font color="#4169E1">return</font>(0);
236
<a name="line231">231: </a>}
237
<a name="line232">232: </a><font color="#B22222">/* -------------------------------------------------------------------------- */</font>
238
<a name="line233">233: </a><font color="#B22222">/*</font>
239
<a name="line234">234: </a><font color="#B22222"> PCApplySymmetricLeftOrRight_Jacobi - Applies the left or right part of a</font>
240
<a name="line235">235: </a><font color="#B22222"> symmetric preconditioner to a vector.</font>
242
<a name="line237">237: </a><font color="#B22222"> Input Parameters:</font>
243
<a name="line238">238: </a><font color="#B22222">. pc - the preconditioner context</font>
244
<a name="line239">239: </a><font color="#B22222">. x - input vector</font>
246
<a name="line241">241: </a><font color="#B22222"> Output Parameter:</font>
247
<a name="line242">242: </a><font color="#B22222">. y - output vector</font>
249
<a name="line244">244: </a><font color="#B22222"> Application Interface Routines: <A href="../../../../../docs/manualpages/PC/PCApplySymmetricLeft.html#PCApplySymmetricLeft">PCApplySymmetricLeft</A>(), <A href="../../../../../docs/manualpages/PC/PCApplySymmetricRight.html#PCApplySymmetricRight">PCApplySymmetricRight</A>()</font>
250
<a name="line245">245: </a><font color="#B22222">*/</font>
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<a name="line246">246: </a><strong><font color="#4169E1"><a name="PCApplySymmetricLeftOrRight_Jacobi"></a>static int PCApplySymmetricLeftOrRight_Jacobi(<A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A> pc,<A href="../../../../../docs/manualpages/Vec/Vec.html#Vec">Vec</A> x,<A href="../../../../../docs/manualpages/Vec/Vec.html#Vec">Vec</A> y)</font></strong>
252
<a name="line247">247: </a>{
253
<a name="line248">248: </a> int ierr;
254
<a name="line249">249: </a> PC_Jacobi *jac = (PC_Jacobi*)pc->data;
256
<a name="line252">252: </a> <font color="#4169E1">if</font> (!jac->diagsqrt) {
257
<a name="line253">253: </a> PCSetUp_Jacobi_Symmetric(pc);
258
<a name="line254">254: </a> }
259
<a name="line255">255: </a> <A href="../../../../../docs/manualpages/Vec/VecPointwiseMult.html#VecPointwiseMult">VecPointwiseMult</A>(x,jac->diagsqrt,y);
260
<a name="line256">256: </a> <font color="#4169E1">return</font>(0);
261
<a name="line257">257: </a>}
262
<a name="line258">258: </a><font color="#B22222">/* -------------------------------------------------------------------------- */</font>
263
<a name="line259">259: </a><font color="#B22222">/*</font>
264
<a name="line260">260: </a><font color="#B22222"> PCDestroy_Jacobi - Destroys the private context for the Jacobi preconditioner</font>
265
<a name="line261">261: </a><font color="#B22222"> that was created with PCCreate_Jacobi().</font>
267
<a name="line263">263: </a><font color="#B22222"> Input Parameter:</font>
268
<a name="line264">264: </a><font color="#B22222">. pc - the preconditioner context</font>
270
<a name="line266">266: </a><font color="#B22222"> Application Interface Routine: <A href="../../../../../docs/manualpages/PC/PCDestroy.html#PCDestroy">PCDestroy</A>()</font>
271
<a name="line267">267: </a><font color="#B22222">*/</font>
272
<a name="line268">268: </a><strong><font color="#4169E1"><a name="PCDestroy_Jacobi"></a>static int PCDestroy_Jacobi(<A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A> pc)</font></strong>
273
<a name="line269">269: </a>{
274
<a name="line270">270: </a> PC_Jacobi *jac = (PC_Jacobi*)pc->data;
275
<a name="line271">271: </a> int ierr;
277
<a name="line274">274: </a> <font color="#4169E1">if</font> (jac->diag) {<A href="../../../../../docs/manualpages/Vec/VecDestroy.html#VecDestroy">VecDestroy</A>(jac->diag);}
278
<a name="line275">275: </a> <font color="#4169E1">if</font> (jac->diagsqrt) {<A href="../../../../../docs/manualpages/Vec/VecDestroy.html#VecDestroy">VecDestroy</A>(jac->diagsqrt);}
280
<a name="line277">277: </a> <font color="#B22222">/*</font>
281
<a name="line278">278: </a><font color="#B22222"> Free the private data structure that was hanging off the <A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A></font>
282
<a name="line279">279: </a><font color="#B22222"> */</font>
283
<a name="line280">280: </a> <A href="../../../../../docs/manualpages/Sys/PetscFree.html#PetscFree">PetscFree</A>(jac);
284
<a name="line281">281: </a> <font color="#4169E1">return</font>(0);
285
<a name="line282">282: </a>}
287
<a name="line284">284: </a><strong><font color="#4169E1"><a name="PCSetFromOptions_Jacobi"></a>static int PCSetFromOptions_Jacobi(<A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A> pc)</font></strong>
288
<a name="line285">285: </a>{
289
<a name="line286">286: </a> PC_Jacobi *jac = (PC_Jacobi*)pc->data;
290
<a name="line287">287: </a> int ierr;
292
<a name="line290">290: </a> <A href="../../../../../docs/manualpages/Sys/PetscOptionsHead.html#PetscOptionsHead">PetscOptionsHead</A>(<font color="#666666">"Jacobi options"</font>);
293
<a name="line291">291: </a> <A href="../../../../../docs/manualpages/Sys/PetscOptionsLogical.html#PetscOptionsLogical">PetscOptionsLogical</A>(<font color="#666666">"-pc_jacobi_rowmax"</font>,<font color="#666666">"Use row maximums for diagonal"</font>,<font color="#666666">"<A href="../../../../../docs/manualpages/PC/PCJacobiSetUseRowMax.html#PCJacobiSetUseRowMax">PCJacobiSetUseRowMax</A>"</font>,jac->userowmax,
294
<a name="line292">292: </a> &jac->userowmax,PETSC_NULL);
295
<a name="line293">293: </a> <A href="../../../../../docs/manualpages/Sys/PetscOptionsTail.html#PetscOptionsTail">PetscOptionsTail</A>();
296
<a name="line294">294: </a> <font color="#4169E1">return</font>(0);
297
<a name="line295">295: </a>}
299
<a name="line297">297: </a><font color="#B22222">/* -------------------------------------------------------------------------- */</font>
300
<a name="line298">298: </a><font color="#B22222">/*</font>
301
<a name="line299">299: </a><font color="#B22222"> PCCreate_Jacobi - Creates a Jacobi preconditioner context, PC_Jacobi, </font>
302
<a name="line300">300: </a><font color="#B22222"> and sets this as the private data within the generic preconditioning </font>
303
<a name="line301">301: </a><font color="#B22222"> context, <A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A>, that was created within <A href="../../../../../docs/manualpages/PC/PCCreate.html#PCCreate">PCCreate</A>().</font>
305
<a name="line303">303: </a><font color="#B22222"> Input Parameter:</font>
306
<a name="line304">304: </a><font color="#B22222">. pc - the preconditioner context</font>
308
<a name="line306">306: </a><font color="#B22222"> Application Interface Routine: <A href="../../../../../docs/manualpages/PC/PCCreate.html#PCCreate">PCCreate</A>()</font>
309
<a name="line307">307: </a><font color="#B22222">*/</font>
310
<a name="line308">308: </a><strong><font color="#4169E1"><a name="PCCreate_Jacobi"></a>EXTERN_C_BEGIN</font></strong>
311
<a name="line309">309: </a><strong><font color="#4169E1">int PCCreate_Jacobi(<A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A> pc)</font></strong>
312
<a name="line310">310: </a>{
313
<a name="line311">311: </a> PC_Jacobi *jac;
314
<a name="line312">312: </a> int ierr;
317
<a name="line316">316: </a> <font color="#B22222">/*</font>
318
<a name="line317">317: </a><font color="#B22222"> Creates the private data structure for this preconditioner and</font>
319
<a name="line318">318: </a><font color="#B22222"> attach it to the <A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A> object.</font>
320
<a name="line319">319: </a><font color="#B22222"> */</font>
321
<a name="line320">320: </a> ierr = <A href="../../../../../docs/manualpages/Sys/PetscNew.html#PetscNew">PetscNew</A>(PC_Jacobi,&jac);
322
<a name="line321">321: </a> pc->data = (void*)jac;
324
<a name="line323">323: </a> <font color="#B22222">/*</font>
325
<a name="line324">324: </a><font color="#B22222"> Logs the memory usage; this is not needed but allows PETSc to </font>
326
<a name="line325">325: </a><font color="#B22222"> monitor how much memory is being used for various purposes.</font>
327
<a name="line326">326: </a><font color="#B22222"> */</font>
328
<a name="line327">327: </a> PetscLogObjectMemory(pc,<font color="#4169E1">sizeof</font>(PC_Jacobi));
330
<a name="line329">329: </a> <font color="#B22222">/*</font>
331
<a name="line330">330: </a><font color="#B22222"> Initialize the pointers to vectors to ZERO; these will be used to store</font>
332
<a name="line331">331: </a><font color="#B22222"> diagonal entries of the matrix for fast preconditioner application.</font>
333
<a name="line332">332: </a><font color="#B22222"> */</font>
334
<a name="line333">333: </a> jac->diag = 0;
335
<a name="line334">334: </a> jac->diagsqrt = 0;
336
<a name="line335">335: </a> jac->userowmax = PETSC_FALSE;
338
<a name="line337">337: </a> <font color="#B22222">/*</font>
339
<a name="line338">338: </a><font color="#B22222"> Set the pointers for the functions that are provided above.</font>
340
<a name="line339">339: </a><font color="#B22222"> Now when the user-level routines (such as <A href="../../../../../docs/manualpages/PC/PCApply.html#PCApply">PCApply</A>(), <A href="../../../../../docs/manualpages/PC/PCDestroy.html#PCDestroy">PCDestroy</A>(), etc.)</font>
341
<a name="line340">340: </a><font color="#B22222"> are called, they will automatically call these functions. Note we</font>
342
<a name="line341">341: </a><font color="#B22222"> choose not to provide a couple of these functions since they are</font>
343
<a name="line342">342: </a><font color="#B22222"> not needed.</font>
344
<a name="line343">343: </a><font color="#B22222"> */</font>
345
<a name="line344">344: </a> pc->ops->apply = PCApply_Jacobi;
346
<a name="line345">345: </a> pc->ops->applytranspose = PCApply_Jacobi;
347
<a name="line346">346: </a> pc->ops->setup = PCSetUp_Jacobi;
348
<a name="line347">347: </a> pc->ops->destroy = PCDestroy_Jacobi;
349
<a name="line348">348: </a> pc->ops->setfromoptions = PCSetFromOptions_Jacobi;
350
<a name="line349">349: </a> pc->ops->view = 0;
351
<a name="line350">350: </a> pc->ops->applyrichardson = 0;
352
<a name="line351">351: </a> pc->ops->applysymmetricleft = PCApplySymmetricLeftOrRight_Jacobi;
353
<a name="line352">352: </a> pc->ops->applysymmetricright = PCApplySymmetricLeftOrRight_Jacobi;
354
<a name="line353">353: </a> <A href="../../../../../docs/manualpages/Sys/PetscObjectComposeFunctionDynamic.html#PetscObjectComposeFunctionDynamic">PetscObjectComposeFunctionDynamic</A>((<A href="../../../../../docs/manualpages/Sys/PetscObject.html#PetscObject">PetscObject</A>)pc,<font color="#666666">"PCJacobiSetUseRowMax_C"</font>,<font color="#666666">"PCJacobiSetUseRowMax_Jacobi"</font>,
355
<a name="line354">354: </a> PCJacobiSetUseRowMax_Jacobi);
356
<a name="line355">355: </a> <font color="#4169E1">return</font>(0);
357
<a name="line356">356: </a>}
358
<a name="line357">357: </a>EXTERN_C_END
360
<a name="line359">359: </a><font color="#B22222">/*@</font>
361
<a name="line360">360: </a><font color="#B22222"> <A href="../../../../../docs/manualpages/PC/PCJacobiSetUseRowMax.html#PCJacobiSetUseRowMax">PCJacobiSetUseRowMax</A> - Causes the Jacobi preconditioner to use the </font>
362
<a name="line361">361: </a><font color="#B22222"> maximum entry in each row as the diagonal preconditioner, instead of</font>
363
<a name="line362">362: </a><font color="#B22222"> the diagonal entry</font>
365
<a name="line364">364: </a><font color="#B22222"> Collective on <A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A></font>
367
<a name="line366">366: </a><font color="#B22222"> Input Parameters:</font>
368
<a name="line367">367: </a><font color="#B22222">. pc - the preconditioner context</font>
371
<a name="line370">370: </a><font color="#B22222"> Options Database Key:</font>
372
<a name="line371">371: </a><font color="#B22222">. -pc_jacobi_rowmax </font>
374
<a name="line373">373: </a><font color="#B22222"> Level: intermediate</font>
376
<a name="line375">375: </a><font color="#B22222"> Concepts: Jacobi preconditioner</font>
378
<a name="line377">377: </a><font color="#B22222">@*/</font>
379
<a name="line378">378: </a><strong><font color="#4169E1"><a name="PCJacobiSetUseRowMax"></a>int <A href="../../../../../docs/manualpages/PC/PCJacobiSetUseRowMax.html#PCJacobiSetUseRowMax">PCJacobiSetUseRowMax</A>(<A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A> pc)</font></strong>
380
<a name="line379">379: </a>{
381
<a name="line380">380: </a> int ierr,(*f)(<A href="../../../../../docs/manualpages/PC/PC.html#PC">PC</A>);
383
<a name="line384">384: </a> <A href="../../../../../docs/manualpages/Sys/PetscObjectQueryFunction.html#PetscObjectQueryFunction">PetscObjectQueryFunction</A>((<A href="../../../../../docs/manualpages/Sys/PetscObject.html#PetscObject">PetscObject</A>)pc,<font color="#666666">"PCJacobiSetRowMax_C"</font>,(void (**)(void))&f);
384
<a name="line385">385: </a> <font color="#4169E1">if</font> (f) {
385
<a name="line386">386: </a> (*f)(pc);
386
<a name="line387">387: </a> }
387
<a name="line388">388: </a> <font color="#4169E1">return</font>(0);
388
<a name="line389">389: </a>}