SparseLU_relax_snode.h
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00001 // This file is part of Eigen, a lightweight C++ template library
00002 // for linear algebra.
00003 //
00004 // Copyright (C) 2012 Désiré Nuentsa-Wakam <desire.nuentsa_wakam@inria.fr>
00005 //
00006 // This Source Code Form is subject to the terms of the Mozilla
00007 // Public License v. 2.0. If a copy of the MPL was not distributed
00008 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
00009 
00010 /* This file is a modified version of heap_relax_snode.c file in SuperLU
00011  * -- SuperLU routine (version 3.0) --
00012  * Univ. of California Berkeley, Xerox Palo Alto Research Center,
00013  * and Lawrence Berkeley National Lab.
00014  * October 15, 2003
00015  *
00016  * Copyright (c) 1994 by Xerox Corporation.  All rights reserved.
00017  *
00018  * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY
00019  * EXPRESSED OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
00020  *
00021  * Permission is hereby granted to use or copy this program for any
00022  * purpose, provided the above notices are retained on all copies.
00023  * Permission to modify the code and to distribute modified code is
00024  * granted, provided the above notices are retained, and a notice that
00025  * the code was modified is included with the above copyright notice.
00026  */
00027 
00028 #ifndef SPARSELU_RELAX_SNODE_H
00029 #define SPARSELU_RELAX_SNODE_H
00030 
00031 namespace Eigen {
00032 
00033 namespace internal {
00034  
00046 template <typename Scalar, typename Index>
00047 void SparseLUImpl<Scalar,Index>::relax_snode (const Index n, IndexVector& et, const Index relax_columns, IndexVector& descendants, IndexVector& relax_end)
00048 {
00049   
00050   // compute the number of descendants of each node in the etree
00051   Index j, parent; 
00052   relax_end.setConstant(emptyIdxLU);
00053   descendants.setZero();
00054   for (j = 0; j < n; j++) 
00055   {
00056     parent = et(j);
00057     if (parent != n) // not the dummy root
00058       descendants(parent) += descendants(j) + 1;
00059   }
00060   // Identify the relaxed supernodes by postorder traversal of the etree
00061   Index snode_start; // beginning of a snode 
00062   for (j = 0; j < n; )
00063   {
00064     parent = et(j);
00065     snode_start = j; 
00066     while ( parent != n && descendants(parent) < relax_columns ) 
00067     {
00068       j = parent; 
00069       parent = et(j);
00070     }
00071     // Found a supernode in postordered etree, j is the last column 
00072     relax_end(snode_start) = j; // Record last column
00073     j++;
00074     // Search for a new leaf
00075     while (descendants(j) != 0 && j < n) j++;
00076   } // End postorder traversal of the etree
00077   
00078 }
00079 
00080 } // end namespace internal
00081 
00082 } // end namespace Eigen
00083 #endif


acado
Author(s): Milan Vukov, Rien Quirynen
autogenerated on Sat Jun 8 2019 19:39:23