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Added triangular assignement, e.g.:

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m.upper() = a+b;
only updates the upper triangular part of m.
Note that:
 m = (a+b).upper();
updates all coefficients of m (but half of the additions
will be skiped)

Updated back/forward substitution to better use Eigen's capability.
This commit is contained in:
Gael Guennebaud
2008-04-26 19:20:26 +00:00
parent 4c92150676
commit b4c974d059
4 changed files with 120 additions and 59 deletions
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67
Eigen/src/Core/Triangular.h
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@@ -96,49 +96,6 @@ template<int Mode, typename MatrixType> class Triangular
return Triangular<(Upper | Lower) xor Mode, Transpose<MatrixType> >((m_matrix.transpose()));
}
#if 0
template<typename OtherDerived>
Triangular& operator=(const MatrixBase<OtherDerived>& other);
/** Overloaded to provide optimal evaluation loops */
template<typename OtherDerived>
Triangular& operator +=(const MatrixBase<OtherDerived>& other)
{
return *this = m_matrix + other;
}
/** Overloaded to provide optimal evaluation loops */
template<typename OtherDerived>
Triangular& operator *=(const MatrixBase<OtherDerived>& other)
{
return *this = this->lazyProduct(other).eval();
}
/** Optimized triangular matrix - matrix product */
template<typename OtherDerived>
TriangularProduct<Mode, MatrixType, OtherDerived> lazyProduct(const MatrixBase<Scalar, OtherDerived>& other) const
{
return TriangularProduct<Mode,MatrixType,OtherDerived>(m_matrix, other.ref());
}
/** Optimized triangular matrix - matrix product */
template<typename OtherDerived>
Eval<TriangularProduct<Mode, MatrixType, OtherDerived> > operator * (const MatrixBase<Scalar, OtherDerived>& other) const
{
return this->lazyProduct(other).eval();
}
/** Optimized matrix - triangular matrix product */
template<typename OtherDerived>
friend Eval<Transpose<TriangularProduct<0x1 xor Mode, Transpose<MatRef>, Transpose<OtherDerived> > > >
operator * (const MatrixBase<Scalar, OtherDerived>& other, const Triangular<Mode,MatrixType>& tri)
{
return tri.transpose().lazyProduct(other.transpose()).transpose().eval();
}
#endif
/** \returns the product of the inverse of *this with \a other.
*
* This function computes the inverse-matrix matrix product inv(*this) \a other
@@ -159,36 +116,32 @@ template<int Mode, typename MatrixType> class Triangular
{
// forward substitution
if (Flags & UnitDiagBit)
res.col(c)[0] = other.col(c)[0];
res(0,c) = other(0,c);
else
res.col(c)[0] = other.col(c)[0]/_coeff(0, 0);
res(0,c) = other(0,c)/_coeff(0, 0);
for (int i=1 ; i<_rows() ; ++i)
{
Scalar tmp = other.col(c)[i];
for (int j = 0 ; j < i ; ++j)
tmp -= _coeff(i,j) * res.col(c)[j];
Scalar tmp = other(i,c) - ((this->row(i).start(i)).transpose() * res.col(c).start(i))(0,0);
if (Flags & UnitDiagBit)
res.col(c)[i] = tmp;
res(i,c) = tmp;
else
res.col(c)[i] = tmp/_coeff(i,i);
res(i,c) = tmp/_coeff(i,i);
}
}
else
{
// backward substitution
if (Flags & UnitDiagBit)
res.col(c)[_cols()-1] = other.col(c)[_cols()-1];
res(_cols()-1,c) = other(_cols()-1,c);
else
res.col(c)[_cols()-1] = other.col(c)[_cols()-1]/_coeff(_rows()-1, _cols()-1);
res(_cols()-1,c) = other(_cols()-1, c)/_coeff(_rows()-1, _cols()-1);
for (int i=_rows()-2 ; i>=0 ; --i)
{
Scalar tmp = other.col(c)[i];
for (int j = i+1 ; j < _cols() ; ++j)
tmp -= _coeff(i,j) * res.col(c)[j];
Scalar tmp = other(i,c) - ((this->row(i).end(_cols()-i-1)).transpose() * res.col(c).end(_cols()-i-1))(0,0);
if (Flags & UnitDiagBit)
res.col(c)[i] = tmp;
res(i,c) = tmp;
else
res.col(c)[i] = tmp/_coeff(i,i);
res(i,c) = tmp/_coeff(i,i);
}
}
}