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new simplified API to fill sparse matrices (the old functions are

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deprecated). Basically there are now only 2 functions to set a
coefficient:
1) mat.coeffRef(row,col) = value;
2) mat.insert(row,col) = value;
coeffRef has no limitation, insert assumes the coeff has not already
been set, and raises an assert otherwise.
In addition I added a much lower level, but more efficient filling
mechanism for
internal use only.
This commit is contained in:
Gael Guennebaud
2009-05-04 14:25:12 +00:00
parent ddb6e96d48
commit 2829314284
12 changed files with 287 additions and 110 deletions
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10
Eigen/src/Sparse/SparseLLT.h
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@@ -135,7 +135,8 @@ void SparseLLT<MatrixType,Backend>::compute(const MatrixType& a)
RealScalar density = a.nonZeros()/RealScalar(size*size);
// TODO estimate the number of non zeros
m_matrix.startFill(a.nonZeros()*2);
m_matrix.setZero();
m_matrix.reserve(a.nonZeros()*2);
for (int j = 0; j < size; ++j)
{
Scalar x = ei_real(a.coeff(j,j));
@@ -173,14 +174,15 @@ void SparseLLT<MatrixType,Backend>::compute(const MatrixType& a)
// copy the temporary vector to the respective m_matrix.col()
// while scaling the result by 1/real(x)
RealScalar rx = ei_sqrt(ei_real(x));
m_matrix.fill(j,j) = rx;
m_matrix.insert(j,j) = rx; // FIXME use insertBack
Scalar y = Scalar(1)/rx;
for (typename AmbiVector<Scalar>::Iterator it(tempVector, m_precision*rx); it; ++it)
{
m_matrix.fill(it.index(), j) = it.value() * y;
// FIXME use insertBack
m_matrix.insert(it.index(), j) = it.value() * y;
}
}
m_matrix.endFill();
m_matrix.finalize();
}
/** Computes b = L^-T L^-1 b */