Eigen::COLAMDOrdering< Index > Class Template Reference

#include <Ordering.h>

Public Types
typedef PermutationMatrix< Dynamic, Dynamic, Index >	PermutationType
typedef Matrix< Index, Dynamic, 1 >	IndexVector

Public Member Functions
template<typename MatrixType >
void	operator() (const MatrixType &mat, PermutationType &perm)

Detailed Description

template<typename Index>
class Eigen::COLAMDOrdering< Index >

Functor computing the column approximate minimum degree ordering The matrix should be in column-major format

Definition at line 115 of file Ordering.h.

Member Function Documentation

template<typename Index >

template<typename MatrixType >

void Eigen::COLAMDOrdering< Index >::operator() ( const MatrixType &  mat, PermutationType &  perm  )

inline

Compute the permutation vector form a sparse matrix

Definition at line 123 of file Ordering.h.

    {
      Index m = mat.rows();
      Index n = mat.cols();
      Index nnz = mat.nonZeros();
      // Get the recommended value of Alen to be used by colamd
      Index Alen = internal::colamd_recommended(nnz, m, n); 
      // Set the default parameters
      double knobs [COLAMD_KNOBS]; 
      Index stats [COLAMD_STATS];
      internal::colamd_set_defaults(knobs);
      
      Index info;
      IndexVector p(n+1), A(Alen); 
      for(Index i=0; i <= n; i++)   p(i) = mat.outerIndexPtr()[i];
      for(Index i=0; i < nnz; i++)  A(i) = mat.innerIndexPtr()[i];
      // Call Colamd routine to compute the ordering 
      info = internal::colamd(m, n, Alen, A.data(), p.data(), knobs, stats); 
      eigen_assert( info && "COLAMD failed " );
      
      perm.resize(n);
      for (Index i = 0; i < n; i++) perm.indices()(p(i)) = i;
    }

---

The documentation for this class was generated from the following file:

• C:/Users/Brig/Documents/ShapeWorksStudio/src/Surfworks/Eigen/src/OrderingMethods/Ordering.h