Refactoring codes for numeric updates

1 files changed, 92 insertions, 0 deletions

diff --git a/Eigen/src/SparseLU/SparseLU_kernel_bmod.h b/Eigen/src/SparseLU/SparseLU_kernel_bmod.h
new file mode 100644
index 000000000..d5df70fd2
--- /dev/null
+++ b/Eigen/src/SparseLU/SparseLU_kernel_bmod.h
@@ -0,0 +1,92 @@
+// 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>
+//
+// Eigen is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 3 of the License, or (at your option) any later version.
+//
+// Alternatively, you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 2 of
+// the License, or (at your option) any later version.
+//
+// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License and a copy of the GNU General Public License along with
+// Eigen. If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef SPARSELU_KERNEL_BMOD_H
+#define SPARSELU_KERNEL_BMOD_H
+
+/**
+ * \brief Performs numeric block updates from a given supernode to a single column
+ * 
+ * \param segsize Size of the segment (and blocks ) to use for updates
+ * \param [in,out]dense Packed values of the original matrix
+ * \param tempv temporary vector to use for updates
+ * \param lusup array containing the supernodes
+ * \param nsupr Number of rows in the supernode
+ * \param nrow Number of rows in the rectangular part of the supernode
+ * \param lsub compressed row subscripts of supernodes
+ * \param lptr pointer to the first column of the current supernode in lsub
+ * \param no_zeros Number of nonzeros elements before the diagonal part of the supernode
+ * \return 0 on success
+ */
+template <typename BlockScalarVector, typename ScalarVector, typename IndexVector>
+int LU_kernel_bmod(const int segsize, BlockScalarVector& dense, ScalarVector& tempv, ScalarVector& lusup, int& luptr, const int nsupr, const int nrow, IndexVector& lsub, const int lptr, const int no_zeros)
+{
+  typedef typename ScalarVector::Scalar Scalar; 
+  // First, copy U[*,j] segment from dense(*) to tempv(*)
+   // The result of triangular solve is in tempv[*]; 
+    // The result of matric-vector update is in dense[*]
+  int isub = lptr + no_zeros; 
+  int i, irow;
+  for (i = 0; i < segsize; i++)
+  {
+    irow = lsub(isub); 
+    tempv(i) = dense(irow); 
+    ++isub; 
+  }
+  // Dense triangular solve -- start effective triangle
+  luptr += nsupr * no_zeros + no_zeros; 
+  // Form Eigen matrix and vector 
+  Map<Matrix<Scalar,Dynamic,Dynamic>, 0, OuterStride<> > A( &(lusup.data()[luptr]), segsize, segsize, OuterStride<>(nsupr) );
+  VectorBlock<ScalarVector> u(tempv, 0, segsize);
+  
+  u = A.template triangularView<UnitLower>().solve(u); 
+  
+  // Dense matrix-vector product y <-- A*x 
+  luptr += segsize; 
+  new (&A) Map<Matrix<Scalar,Dynamic, Dynamic>, 0, OuterStride<> > ( &(lusup.data()[luptr]), nrow, segsize, OuterStride<>(nsupr) ); 
+  VectorBlock<ScalarVector> l(tempv, segsize, nrow); 
+  l= A * u;
+  
+  // Scatter tempv[] into SPA dense[] as a temporary storage 
+  isub = lptr + no_zeros; 
+  for (i = 0; i < segsize; i++)
+  {
+    irow = lsub(isub); 
+    dense(irow) = tempv(i); 
+    tempv(i) =  Scalar(0.0); 
+    ++isub;
+  }
+  
+  // Scatter l into SPA dense[]
+  for (i = 0; i < nrow; i++)
+  {
+    irow = lsub(isub); 
+    dense(irow) -= l(i); 
+    l(i) = Scalar(0.0); 
+    ++isub; 
+  }
+  
+  return 0; 
+}
+#endif
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