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diff --git a/Eigen/src/SparseLU/SparseLU_pruneL.h b/Eigen/src/SparseLU/SparseLU_pruneL.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 [s,d,c,z]pruneL.c file in SuperLU
+
+ * -- SuperLU routine (version 2.0) --
+ * Univ. of California Berkeley, Xerox Palo Alto Research Center,
+ * and Lawrence Berkeley National Lab.
+ * November 15, 1997
+ *
+ * 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_PRUNEL_H
+#define SPARSELU_PRUNEL_H
+
+namespace Eigen {
+namespace internal {
+
+/**
+ * \brief Prunes the L-structure.
+ *
+ * It prunes the L-structure of supernodes whose L-structure contains the current pivot row "pivrow"
+ *
+ *
+ * \param jcol The current column of L
+ * \param[in] perm_r Row permutation
+ * \param[out] pivrow The pivot row
+ * \param nseg Number of segments
+ * \param segrep
+ * \param repfnz
+ * \param[out] xprune
+ * \param glu Global LU data
+ *
+ */
+template <typename Scalar, typename Index>
+void SparseLUImpl<Scalar,Index>::pruneL(const Index jcol, const IndexVector& perm_r, const Index pivrow, const Index nseg, const IndexVector& segrep, BlockIndexVector repfnz, IndexVector& xprune, GlobalLU_t& glu)
+{
+ // For each supernode-rep irep in U(*,j]
+ Index jsupno = glu.supno(jcol);
+ Index i,irep,irep1;
+ bool movnum, do_prune = false;
+ Index kmin = 0, kmax = 0, minloc, maxloc,krow;
+ for (i = 0; i < nseg; i++)
+ {
+ irep = segrep(i);
+ irep1 = irep + 1;
+ do_prune = false;
+
+ // Don't prune with a zero U-segment
+ if (repfnz(irep) == emptyIdxLU) continue;
+
+ // If a snode overlaps with the next panel, then the U-segment
+ // is fragmented into two parts -- irep and irep1. We should let
+ // pruning occur at the rep-column in irep1s snode.
+ if (glu.supno(irep) == glu.supno(irep1) ) continue; // don't prune
+
+ // If it has not been pruned & it has a nonz in row L(pivrow,i)
+ if (glu.supno(irep) != jsupno )
+ {
+ if ( xprune (irep) >= glu.xlsub(irep1) )
+ {
+ kmin = glu.xlsub(irep);
+ kmax = glu.xlsub(irep1) - 1;
+ for (krow = kmin; krow <= kmax; krow++)
+ {
+ if (glu.lsub(krow) == pivrow)
+ {
+ do_prune = true;
+ break;
+ }
+ }
+ }
+
+ if (do_prune)
+ {
+ // do a quicksort-type partition
+ // movnum=true means that the num values have to be exchanged
+ movnum = false;
+ if (irep == glu.xsup(glu.supno(irep)) ) // Snode of size 1
+ movnum = true;
+
+ while (kmin <= kmax)
+ {
+ if (perm_r(glu.lsub(kmax)) == emptyIdxLU)
+ kmax--;
+ else if ( perm_r(glu.lsub(kmin)) != emptyIdxLU)
+ kmin++;
+ else
+ {
+ // kmin below pivrow (not yet pivoted), and kmax
+ // above pivrow: interchange the two suscripts
+ std::swap(glu.lsub(kmin), glu.lsub(kmax));
+
+ // If the supernode has only one column, then we
+ // only keep one set of subscripts. For any subscript
+ // intercnahge performed, similar interchange must be
+ // done on the numerical values.
+ if (movnum)
+ {
+ minloc = glu.xlusup(irep) + ( kmin - glu.xlsub(irep) );
+ maxloc = glu.xlusup(irep) + ( kmax - glu.xlsub(irep) );
+ std::swap(glu.lusup(minloc), glu.lusup(maxloc));
+ }
+ kmin++;
+ kmax--;
+ }
+ } // end while
+
+ xprune(irep) = kmin; //Pruning
+ } // end if do_prune
+ } // end pruning
+ } // End for each U-segment
+}
+
+} // end namespace internal
+} // end namespace Eigen
+
+#endif // SPARSELU_PRUNEL_H