Squashed 'third_party/eigen/' content from commit 61d72f6

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diff --git a/Eigen/src/SparseLU/SparseLU_SupernodalMatrix.h b/Eigen/src/SparseLU/SparseLU_SupernodalMatrix.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>
+// Copyright (C) 2012 Gael Guennebaud <gael.guennebaud@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/.
+
+#ifndef EIGEN_SPARSELU_SUPERNODAL_MATRIX_H
+#define EIGEN_SPARSELU_SUPERNODAL_MATRIX_H
+
+namespace Eigen {
+namespace internal {
+
+/** \ingroup SparseLU_Module
+ * \brief a class to manipulate the L supernodal factor from the SparseLU factorization
+ * 
+ * This class  contain the data to easily store 
+ * and manipulate the supernodes during the factorization and solution phase of Sparse LU. 
+ * Only the lower triangular matrix has supernodes.
+ * 
+ * NOTE : This class corresponds to the SCformat structure in SuperLU
+ * 
+ */
+/* TODO
+ * InnerIterator as for sparsematrix 
+ * SuperInnerIterator to iterate through all supernodes 
+ * Function for triangular solve
+ */
+template <typename _Scalar, typename _Index>
+class MappedSuperNodalMatrix
+{
+  public:
+    typedef _Scalar Scalar; 
+    typedef _Index Index;
+    typedef Matrix<Index,Dynamic,1> IndexVector; 
+    typedef Matrix<Scalar,Dynamic,1> ScalarVector;
+  public:
+    MappedSuperNodalMatrix()
+    {
+      
+    }
+    MappedSuperNodalMatrix(Index m, Index n,  ScalarVector& nzval, IndexVector& nzval_colptr, IndexVector& rowind, 
+             IndexVector& rowind_colptr, IndexVector& col_to_sup, IndexVector& sup_to_col )
+    {
+      setInfos(m, n, nzval, nzval_colptr, rowind, rowind_colptr, col_to_sup, sup_to_col);
+    }
+    
+    ~MappedSuperNodalMatrix()
+    {
+      
+    }
+    /**
+     * Set appropriate pointers for the lower triangular supernodal matrix
+     * These infos are available at the end of the numerical factorization
+     * FIXME This class will be modified such that it can be use in the course 
+     * of the factorization.
+     */
+    void setInfos(Index m, Index n, ScalarVector& nzval, IndexVector& nzval_colptr, IndexVector& rowind, 
+             IndexVector& rowind_colptr, IndexVector& col_to_sup, IndexVector& sup_to_col )
+    {
+      m_row = m;
+      m_col = n; 
+      m_nzval = nzval.data(); 
+      m_nzval_colptr = nzval_colptr.data(); 
+      m_rowind = rowind.data(); 
+      m_rowind_colptr = rowind_colptr.data(); 
+      m_nsuper = col_to_sup(n); 
+      m_col_to_sup = col_to_sup.data(); 
+      m_sup_to_col = sup_to_col.data(); 
+    }
+    
+    /**
+     * Number of rows
+     */
+    Index rows() { return m_row; }
+    
+    /**
+     * Number of columns
+     */
+    Index cols() { return m_col; }
+    
+    /**
+     * Return the array of nonzero values packed by column
+     * 
+     * The size is nnz
+     */
+    Scalar* valuePtr() {  return m_nzval; }
+    
+    const Scalar* valuePtr() const 
+    {
+      return m_nzval; 
+    }
+    /**
+     * Return the pointers to the beginning of each column in \ref valuePtr()
+     */
+    Index* colIndexPtr()
+    {
+      return m_nzval_colptr; 
+    }
+    
+    const Index* colIndexPtr() const
+    {
+      return m_nzval_colptr; 
+    }
+    
+    /**
+     * Return the array of compressed row indices of all supernodes
+     */
+    Index* rowIndex()  { return m_rowind; }
+    
+    const Index* rowIndex() const
+    {
+      return m_rowind; 
+    }
+    
+    /**
+     * Return the location in \em rowvaluePtr() which starts each column
+     */
+    Index* rowIndexPtr() { return m_rowind_colptr; }
+    
+    const Index* rowIndexPtr() const 
+    {
+      return m_rowind_colptr; 
+    }
+    
+    /** 
+     * Return the array of column-to-supernode mapping 
+     */
+    Index* colToSup()  { return m_col_to_sup; }
+    
+    const Index* colToSup() const
+    {
+      return m_col_to_sup;       
+    }
+    /**
+     * Return the array of supernode-to-column mapping
+     */
+    Index* supToCol() { return m_sup_to_col; }
+    
+    const Index* supToCol() const 
+    {
+      return m_sup_to_col;
+    }
+    
+    /**
+     * Return the number of supernodes
+     */
+    Index nsuper() const 
+    {
+      return m_nsuper; 
+    }
+    
+    class InnerIterator; 
+    template<typename Dest>
+    void solveInPlace( MatrixBase<Dest>&X) const;
+    
+      
+      
+    
+  protected:
+    Index m_row; // Number of rows
+    Index m_col; // Number of columns 
+    Index m_nsuper; // Number of supernodes 
+    Scalar* m_nzval; //array of nonzero values packed by column
+    Index* m_nzval_colptr; //nzval_colptr[j] Stores the location in nzval[] which starts column j 
+    Index* m_rowind; // Array of compressed row indices of rectangular supernodes
+    Index* m_rowind_colptr; //rowind_colptr[j] stores the location in rowind[] which starts column j
+    Index* m_col_to_sup; // col_to_sup[j] is the supernode number to which column j belongs
+    Index* m_sup_to_col; //sup_to_col[s] points to the starting column of the s-th supernode
+    
+  private :
+};
+
+/**
+  * \brief InnerIterator class to iterate over nonzero values of the current column in the supernodal matrix L
+  * 
+  */
+template<typename Scalar, typename Index>
+class MappedSuperNodalMatrix<Scalar,Index>::InnerIterator
+{
+  public:
+     InnerIterator(const MappedSuperNodalMatrix& mat, Index outer)
+      : m_matrix(mat),
+        m_outer(outer), 
+        m_supno(mat.colToSup()[outer]),
+        m_idval(mat.colIndexPtr()[outer]),
+        m_startidval(m_idval),
+        m_endidval(mat.colIndexPtr()[outer+1]),
+        m_idrow(mat.rowIndexPtr()[mat.supToCol()[mat.colToSup()[outer]]]),
+        m_endidrow(mat.rowIndexPtr()[mat.supToCol()[mat.colToSup()[outer]]+1])
+    {}
+    inline InnerIterator& operator++()
+    { 
+      m_idval++; 
+      m_idrow++;
+      return *this;
+    }
+    inline Scalar value() const { return m_matrix.valuePtr()[m_idval]; }
+    
+    inline Scalar& valueRef() { return const_cast<Scalar&>(m_matrix.valuePtr()[m_idval]); }
+    
+    inline Index index() const { return m_matrix.rowIndex()[m_idrow]; }
+    inline Index row() const { return index(); }
+    inline Index col() const { return m_outer; }
+    
+    inline Index supIndex() const { return m_supno; }
+    
+    inline operator bool() const 
+    { 
+      return ( (m_idval < m_endidval) && (m_idval >= m_startidval)
+                && (m_idrow < m_endidrow) );
+    }
+    
+  protected:
+    const MappedSuperNodalMatrix& m_matrix; // Supernodal lower triangular matrix 
+    const Index m_outer;                    // Current column 
+    const Index m_supno;                    // Current SuperNode number
+    Index m_idval;                          // Index to browse the values in the current column
+    const Index m_startidval;               // Start of the column value
+    const Index m_endidval;                 // End of the column value
+    Index m_idrow;                          // Index to browse the row indices 
+    Index m_endidrow;                       // End index of row indices of the current column
+};
+
+/**
+ * \brief Solve with the supernode triangular matrix
+ * 
+ */
+template<typename Scalar, typename Index>
+template<typename Dest>
+void MappedSuperNodalMatrix<Scalar,Index>::solveInPlace( MatrixBase<Dest>&X) const
+{
+    Index n = X.rows(); 
+    Index nrhs = X.cols(); 
+    const Scalar * Lval = valuePtr();                 // Nonzero values 
+    Matrix<Scalar,Dynamic,Dynamic> work(n, nrhs);     // working vector
+    work.setZero();
+    for (Index k = 0; k <= nsuper(); k ++)
+    {
+      Index fsupc = supToCol()[k];                    // First column of the current supernode 
+      Index istart = rowIndexPtr()[fsupc];            // Pointer index to the subscript of the current column
+      Index nsupr = rowIndexPtr()[fsupc+1] - istart;  // Number of rows in the current supernode
+      Index nsupc = supToCol()[k+1] - fsupc;          // Number of columns in the current supernode
+      Index nrow = nsupr - nsupc;                     // Number of rows in the non-diagonal part of the supernode
+      Index irow;                                     //Current index row
+      
+      if (nsupc == 1 )
+      {
+        for (Index j = 0; j < nrhs; j++)
+        {
+          InnerIterator it(*this, fsupc);
+          ++it; // Skip the diagonal element
+          for (; it; ++it)
+          {
+            irow = it.row();
+            X(irow, j) -= X(fsupc, j) * it.value();
+          }
+        }
+      }
+      else
+      {
+        // The supernode has more than one column 
+        Index luptr = colIndexPtr()[fsupc]; 
+        Index lda = colIndexPtr()[fsupc+1] - luptr;
+        
+        // Triangular solve 
+        Map<const Matrix<Scalar,Dynamic,Dynamic>, 0, OuterStride<> > A( &(Lval[luptr]), nsupc, nsupc, OuterStride<>(lda) ); 
+        Map< Matrix<Scalar,Dynamic,Dynamic>, 0, OuterStride<> > U (&(X(fsupc,0)), nsupc, nrhs, OuterStride<>(n) ); 
+        U = A.template triangularView<UnitLower>().solve(U); 
+        
+        // Matrix-vector product 
+        new (&A) Map<const Matrix<Scalar,Dynamic,Dynamic>, 0, OuterStride<> > ( &(Lval[luptr+nsupc]), nrow, nsupc, OuterStride<>(lda) ); 
+        work.block(0, 0, nrow, nrhs) = A * U; 
+        
+        //Begin Scatter 
+        for (Index j = 0; j < nrhs; j++)
+        {
+          Index iptr = istart + nsupc; 
+          for (Index i = 0; i < nrow; i++)
+          {
+            irow = rowIndex()[iptr]; 
+            X(irow, j) -= work(i, j); // Scatter operation
+            work(i, j) = Scalar(0); 
+            iptr++;
+          }
+        }
+      }
+    } 
+}
+
+} // end namespace internal
+
+} // end namespace Eigen
+
+#endif // EIGEN_SPARSELU_MATRIX_H