17faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez// This file is part of Eigen, a lightweight C++ template library 27faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez// for linear algebra. 37faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez// 47faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez// Copyright (C) 2012 Désiré Nuentsa-Wakam <desire.nuentsa_wakam@inria.fr> 57faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez// 67faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez// This Source Code Form is subject to the terms of the Mozilla 77faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez// Public License v. 2.0. If a copy of the MPL was not distributed 87faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez// with this file, You can obtain one at http://mozilla.org/MPL/2.0/. 97faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez 107faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez/* This file is a modified version of heap_relax_snode.c file in SuperLU 117faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * -- SuperLU routine (version 3.0) -- 127faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * Univ. of California Berkeley, Xerox Palo Alto Research Center, 137faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * and Lawrence Berkeley National Lab. 147faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * October 15, 2003 157faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * 167faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * Copyright (c) 1994 by Xerox Corporation. All rights reserved. 177faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * 187faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY 197faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * EXPRESSED OR IMPLIED. ANY USE IS AT YOUR OWN RISK. 207faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * 217faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * Permission is hereby granted to use or copy this program for any 227faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * purpose, provided the above notices are retained on all copies. 237faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * Permission to modify the code and to distribute modified code is 247faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * granted, provided the above notices are retained, and a notice that 257faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * the code was modified is included with the above copyright notice. 267faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez */ 277faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez 287faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez#ifndef SPARSELU_RELAX_SNODE_H 297faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez#define SPARSELU_RELAX_SNODE_H 307faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez 317faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandeznamespace Eigen { 327faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez 337faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandeznamespace internal { 347faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez 357faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez/** 367faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * \brief Identify the initial relaxed supernodes 377faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * 387faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * This routine is applied to a column elimination tree. 397faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * It assumes that the matrix has been reordered according to the postorder of the etree 407faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * \param n the number of columns 417faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * \param et elimination tree 427faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * \param relax_columns Maximum number of columns allowed in a relaxed snode 437faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * \param descendants Number of descendants of each node in the etree 447faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez * \param relax_end last column in a supernode 457faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez */ 467faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandeztemplate <typename Scalar, typename Index> 477faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandezvoid SparseLUImpl<Scalar,Index>::relax_snode (const Index n, IndexVector& et, const Index relax_columns, IndexVector& descendants, IndexVector& relax_end) 487faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez{ 497faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez 507faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez // compute the number of descendants of each node in the etree 517faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez Index j, parent; 527faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez relax_end.setConstant(emptyIdxLU); 537faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez descendants.setZero(); 547faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez for (j = 0; j < n; j++) 557faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez { 567faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez parent = et(j); 577faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez if (parent != n) // not the dummy root 587faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez descendants(parent) += descendants(j) + 1; 597faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez } 607faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez // Identify the relaxed supernodes by postorder traversal of the etree 617faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez Index snode_start; // beginning of a snode 627faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez for (j = 0; j < n; ) 637faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez { 647faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez parent = et(j); 657faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez snode_start = j; 667faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez while ( parent != n && descendants(parent) < relax_columns ) 677faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez { 687faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez j = parent; 697faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez parent = et(j); 707faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez } 717faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez // Found a supernode in postordered etree, j is the last column 727faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez relax_end(snode_start) = j; // Record last column 737faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez j++; 747faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez // Search for a new leaf 757faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez while (descendants(j) != 0 && j < n) j++; 767faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez } // End postorder traversal of the etree 777faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez 787faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez} 797faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez 807faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez} // end namespace internal 817faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez 827faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez} // end namespace Eigen 837faaa9f3f0df9d23790277834d426c3d992ac3baCarlos Hernandez#endif 84