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finally, the correct way of dealing with zero matrices in solve()

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This commit is contained in:
Benoit Jacob 2009-08-24 10:51:07 -04:00
parent b8106e97b4
commit 3288e5157a
1 changed files with 10 additions and 2 deletions
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12
Eigen/src/LU/LU.h
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@ -534,7 +534,16 @@ bool LU<MatrixType>::solve(
) const ) const
{ {
ei_assert(m_originalMatrix != 0 && "LU is not initialized."); ei_assert(m_originalMatrix != 0 && "LU is not initialized.");
if(m_rank==0) return false; result->resize(m_lu.cols(), b.cols());
if(m_rank==0)
{
if(b.squaredNorm() == RealScalar(0))
{
result->setZero();
return true;
}
else return false;
}
/* The decomposition PAQ = LU can be rewritten as A = P^{-1} L U Q^{-1}. /* The decomposition PAQ = LU can be rewritten as A = P^{-1} L U Q^{-1}.
* So we proceed as follows: * So we proceed as follows:
@ -577,7 +586,6 @@ bool LU<MatrixType>::solve(
.solveInPlace(c.corner(TopLeft, m_rank, c.cols())); .solveInPlace(c.corner(TopLeft, m_rank, c.cols()));
// Step 4 // Step 4
result->resize(m_lu.cols(), b.cols());
for(int i = 0; i < m_rank; ++i) result->row(m_q.coeff(i)) = c.row(i); for(int i = 0; i < m_rank; ++i) result->row(m_q.coeff(i)) = c.row(i);
for(int i = m_rank; i < m_lu.cols(); ++i) result->row(m_q.coeff(i)).setZero(); for(int i = m_rank; i < m_lu.cols(); ++i) result->row(m_q.coeff(i)).setZero();
return true; return true;