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diff --git a/Eigen/src/SparseLU/SparseLU_pivotL.h b/Eigen/src/SparseLU/SparseLU_pivotL.h
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+// This file is part of Eigen, a lightweight C++ template library
+// for linear algebra.
+//
+// Copyright (C) 2012 Désiré Nuentsa-Wakam <desire.nuentsa_wakam@inria.fr>
+//
+// This Source Code Form is subject to the terms of the Mozilla
+// Public License v. 2.0. If a copy of the MPL was not distributed
+// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+/*
+
+ * NOTE: This file is the modified version of xpivotL.c file in SuperLU
+
+ * -- SuperLU routine (version 3.0) --
+ * Univ. of California Berkeley, Xerox Palo Alto Research Center,
+ * and Lawrence Berkeley National Lab.
+ * October 15, 2003
+ *
+ * Copyright (c) 1994 by Xerox Corporation. All rights reserved.
+ *
+ * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY
+ * EXPRESSED OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
+ *
+ * Permission is hereby granted to use or copy this program for any
+ * purpose, provided the above notices are retained on all copies.
+ * Permission to modify the code and to distribute modified code is
+ * granted, provided the above notices are retained, and a notice that
+ * the code was modified is included with the above copyright notice.
+ */
+#ifndef SPARSELU_PIVOTL_H
+#define SPARSELU_PIVOTL_H
+
+namespace Eigen {
+namespace internal {
+
+/**
+ * \brief Performs the numerical pivotin on the current column of L, and the CDIV operation.
+ *
+ * Pivot policy :
+ * (1) Compute thresh = u * max_(i>=j) abs(A_ij);
+ * (2) IF user specifies pivot row k and abs(A_kj) >= thresh THEN
+ * pivot row = k;
+ * ELSE IF abs(A_jj) >= thresh THEN
+ * pivot row = j;
+ * ELSE
+ * pivot row = m;
+ *
+ * Note: If you absolutely want to use a given pivot order, then set u=0.0.
+ *
+ * \param jcol The current column of L
+ * \param diagpivotthresh diagonal pivoting threshold
+ * \param[in,out] perm_r Row permutation (threshold pivoting)
+ * \param[in] iperm_c column permutation - used to finf diagonal of Pc*A*Pc'
+ * \param[out] pivrow The pivot row
+ * \param glu Global LU data
+ * \return 0 if success, i > 0 if U(i,i) is exactly zero
+ *
+ */
+template <typename Scalar, typename Index>
+Index SparseLUImpl<Scalar,Index>::pivotL(const Index jcol, const RealScalar& diagpivotthresh, IndexVector& perm_r, IndexVector& iperm_c, Index& pivrow, GlobalLU_t& glu)
+{
+
+ Index fsupc = (glu.xsup)((glu.supno)(jcol)); // First column in the supernode containing the column jcol
+ Index nsupc = jcol - fsupc; // Number of columns in the supernode portion, excluding jcol; nsupc >=0
+ Index lptr = glu.xlsub(fsupc); // pointer to the starting location of the row subscripts for this supernode portion
+ Index nsupr = glu.xlsub(fsupc+1) - lptr; // Number of rows in the supernode
+ Index lda = glu.xlusup(fsupc+1) - glu.xlusup(fsupc); // leading dimension
+ Scalar* lu_sup_ptr = &(glu.lusup.data()[glu.xlusup(fsupc)]); // Start of the current supernode
+ Scalar* lu_col_ptr = &(glu.lusup.data()[glu.xlusup(jcol)]); // Start of jcol in the supernode
+ Index* lsub_ptr = &(glu.lsub.data()[lptr]); // Start of row indices of the supernode
+
+ // Determine the largest abs numerical value for partial pivoting
+ Index diagind = iperm_c(jcol); // diagonal index
+ RealScalar pivmax = 0.0;
+ Index pivptr = nsupc;
+ Index diag = emptyIdxLU;
+ RealScalar rtemp;
+ Index isub, icol, itemp, k;
+ for (isub = nsupc; isub < nsupr; ++isub) {
+ using std::abs;
+ rtemp = abs(lu_col_ptr[isub]);
+ if (rtemp > pivmax) {
+ pivmax = rtemp;
+ pivptr = isub;
+ }
+ if (lsub_ptr[isub] == diagind) diag = isub;
+ }
+
+ // Test for singularity
+ if ( pivmax == 0.0 ) {
+ pivrow = lsub_ptr[pivptr];
+ perm_r(pivrow) = jcol;
+ return (jcol+1);
+ }
+
+ RealScalar thresh = diagpivotthresh * pivmax;
+
+ // Choose appropriate pivotal element
+
+ {
+ // Test if the diagonal element can be used as a pivot (given the threshold value)
+ if (diag >= 0 )
+ {
+ // Diagonal element exists
+ using std::abs;
+ rtemp = abs(lu_col_ptr[diag]);
+ if (rtemp != 0.0 && rtemp >= thresh) pivptr = diag;
+ }
+ pivrow = lsub_ptr[pivptr];
+ }
+
+ // Record pivot row
+ perm_r(pivrow) = jcol;
+ // Interchange row subscripts
+ if (pivptr != nsupc )
+ {
+ std::swap( lsub_ptr[pivptr], lsub_ptr[nsupc] );
+ // Interchange numerical values as well, for the two rows in the whole snode
+ // such that L is indexed the same way as A
+ for (icol = 0; icol <= nsupc; icol++)
+ {
+ itemp = pivptr + icol * lda;
+ std::swap(lu_sup_ptr[itemp], lu_sup_ptr[nsupc + icol * lda]);
+ }
+ }
+ // cdiv operations
+ Scalar temp = Scalar(1.0) / lu_col_ptr[nsupc];
+ for (k = nsupc+1; k < nsupr; k++)
+ lu_col_ptr[k] *= temp;
+ return 0;
+}
+
+} // end namespace internal
+} // end namespace Eigen
+
+#endif // SPARSELU_PIVOTL_H