1 // This file is part of Eigen, a lightweight C++ template library 2 // for linear algebra. 3 // 4 // Copyright (C) 2012 Désiré Nuentsa-Wakam <desire.nuentsa_wakam@inria.fr> 5 // 6 // This Source Code Form is subject to the terms of the Mozilla 7 // Public License v. 2.0. If a copy of the MPL was not distributed 8 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/. 9 10 /* 11 * NOTE: This file comes from a partly modified version of files slu_[s,d,c,z]defs.h 12 * -- SuperLU routine (version 4.1) -- 13 * Univ. of California Berkeley, Xerox Palo Alto Research Center, 14 * and Lawrence Berkeley National Lab. 15 * November, 2010 16 * 17 * Global data structures used in LU factorization - 18 * 19 * nsuper: #supernodes = nsuper + 1, numbered [0, nsuper]. 20 * (xsup,supno): supno[i] is the supernode no to which i belongs; 21 * xsup(s) points to the beginning of the s-th supernode. 22 * e.g. supno 0 1 2 2 3 3 3 4 4 4 4 4 (n=12) 23 * xsup 0 1 2 4 7 12 24 * Note: dfs will be performed on supernode rep. relative to the new 25 * row pivoting ordering 26 * 27 * (xlsub,lsub): lsub[*] contains the compressed subscript of 28 * rectangular supernodes; xlsub[j] points to the starting 29 * location of the j-th column in lsub[*]. Note that xlsub 30 * is indexed by column. 31 * Storage: original row subscripts 32 * 33 * During the course of sparse LU factorization, we also use 34 * (xlsub,lsub) for the purpose of symmetric pruning. For each 35 * supernode {s,s+1,...,t=s+r} with first column s and last 36 * column t, the subscript set 37 * lsub[j], j=xlsub[s], .., xlsub[s+1]-1 38 * is the structure of column s (i.e. structure of this supernode). 39 * It is used for the storage of numerical values. 40 * Furthermore, 41 * lsub[j], j=xlsub[t], .., xlsub[t+1]-1 42 * is the structure of the last column t of this supernode. 43 * It is for the purpose of symmetric pruning. Therefore, the 44 * structural subscripts can be rearranged without making physical 45 * interchanges among the numerical values. 46 * 47 * However, if the supernode has only one column, then we 48 * only keep one set of subscripts. For any subscript interchange 49 * performed, similar interchange must be done on the numerical 50 * values. 51 * 52 * The last column structures (for pruning) will be removed 53 * after the numercial LU factorization phase. 54 * 55 * (xlusup,lusup): lusup[*] contains the numerical values of the 56 * rectangular supernodes; xlusup[j] points to the starting 57 * location of the j-th column in storage vector lusup[*] 58 * Note: xlusup is indexed by column. 59 * Each rectangular supernode is stored by column-major 60 * scheme, consistent with Fortran 2-dim array storage. 61 * 62 * (xusub,ucol,usub): ucol[*] stores the numerical values of 63 * U-columns outside the rectangular supernodes. The row 64 * subscript of nonzero ucol[k] is stored in usub[k]. 65 * xusub[i] points to the starting location of column i in ucol. 66 * Storage: new row subscripts; that is subscripts of PA. 67 */ 68 69 #ifndef EIGEN_LU_STRUCTS 70 #define EIGEN_LU_STRUCTS 71 namespace Eigen { 72 namespace internal { 73 74 typedef enum {LUSUP, UCOL, LSUB, USUB, LLVL, ULVL} MemType; 75 76 template <typename IndexVector, typename ScalarVector> 77 struct LU_GlobalLU_t { 78 typedef typename IndexVector::Scalar Index; 79 IndexVector xsup; //First supernode column ... xsup(s) points to the beginning of the s-th supernode 80 IndexVector supno; // Supernode number corresponding to this column (column to supernode mapping) 81 ScalarVector lusup; // nonzero values of L ordered by columns 82 IndexVector lsub; // Compressed row indices of L rectangular supernodes. 83 IndexVector xlusup; // pointers to the beginning of each column in lusup 84 IndexVector xlsub; // pointers to the beginning of each column in lsub 85 Index nzlmax; // Current max size of lsub 86 Index nzlumax; // Current max size of lusup 87 ScalarVector ucol; // nonzero values of U ordered by columns 88 IndexVector usub; // row indices of U columns in ucol 89 IndexVector xusub; // Pointers to the beginning of each column of U in ucol 90 Index nzumax; // Current max size of ucol 91 Index n; // Number of columns in the matrix 92 Index num_expansions; 93 }; 94 95 // Values to set for performance 96 template <typename Index> 97 struct perfvalues { 98 Index panel_size; // a panel consists of at most <panel_size> consecutive columns 99 Index relax; // To control degree of relaxing supernodes. If the number of nodes (columns) 100 // in a subtree of the elimination tree is less than relax, this subtree is considered 101 // as one supernode regardless of the row structures of those columns 102 Index maxsuper; // The maximum size for a supernode in complete LU 103 Index rowblk; // The minimum row dimension for 2-D blocking to be used; 104 Index colblk; // The minimum column dimension for 2-D blocking to be used; 105 Index fillfactor; // The estimated fills factors for L and U, compared with A 106 }; 107 108 } // end namespace internal 109 110 } // end namespace Eigen 111 #endif // EIGEN_LU_STRUCTS 112