SVD_divide_conquer() [2/4]

bool EigenM2::SVD_divide_conquer	(	const LMatrixCCC *	A,
		LMatrixRRR *	Sigma,
		LMatrixCCC *	U,
		LMatrixCCC *	VT )

Definition at line 420 of file eigen.cpp.

{
  auto old_prec = Real::get_default_prec(); 
  Real::set_default_prec(A->ring().get_precision());
 
  MatrixXmpCCC AXmp(A->numRows(), A->numColumns());
  fill_to_MatrixXmp(*A, AXmp);
 
  Eigen::BDCSVD<MatrixXmpCCC> svd(AXmp, Eigen::ComputeThinU | Eigen::ComputeThinV);
  
  fill_from_MatrixXmp(svd.matrixU(), *U);
  fill_from_MatrixXmp(svd.matrixV().adjoint(), *VT);
  fill_from_MatrixXmp(svd.singularValues(), *Sigma);
 
  Real::set_default_prec(old_prec);
  return true;
}

References fill_from_MatrixXmp(), fill_to_MatrixXmp(), M2::ARingCCC::get_precision(), DMat< ACoeffRing >::numColumns(), DMat< ACoeffRing >::numRows(), and DMat< ACoeffRing >::ring().