diff options
Diffstat (limited to 'Eigen/src/Core/Visitor.h')
-rw-r--r-- | Eigen/src/Core/Visitor.h | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/Eigen/src/Core/Visitor.h b/Eigen/src/Core/Visitor.h index 54c1883d9..b11d87e9f 100644 --- a/Eigen/src/Core/Visitor.h +++ b/Eigen/src/Core/Visitor.h @@ -40,6 +40,14 @@ struct visitor_impl<Visitor, Derived, 1> } }; +// This specialization enables visitors on empty matrices at compile-time +template<typename Visitor, typename Derived> +struct visitor_impl<Visitor, Derived, 0> { + EIGEN_DEVICE_FUNC + static inline void run(const Derived &/*mat*/, Visitor& /*visitor*/) + {} +}; + template<typename Visitor, typename Derived> struct visitor_impl<Visitor, Derived, Dynamic> { @@ -98,6 +106,8 @@ protected: * * \note compared to one or two \em for \em loops, visitors offer automatic * unrolling for small fixed size matrix. + * + * \note if the matrix is empty, then the visitor is left unchanged. * * \sa minCoeff(Index*,Index*), maxCoeff(Index*,Index*), DenseBase::redux() */ @@ -106,6 +116,9 @@ template<typename Visitor> EIGEN_DEVICE_FUNC void DenseBase<Derived>::visit(Visitor& visitor) const { + if(size()==0) + return; + typedef typename internal::visitor_evaluator<Derived> ThisEvaluator; ThisEvaluator thisEval(derived()); @@ -196,6 +209,9 @@ struct functor_traits<max_coeff_visitor<Scalar> > { /** \fn DenseBase<Derived>::minCoeff(IndexType* rowId, IndexType* colId) const * \returns the minimum of all coefficients of *this and puts in *row and *col its location. + * + * \warning the matrix must be not empty, otherwise an assertion is triggered. + * * \warning the result is undefined if \c *this contains NaN. * * \sa DenseBase::minCoeff(Index*), DenseBase::maxCoeff(Index*,Index*), DenseBase::visit(), DenseBase::minCoeff() @@ -206,6 +222,8 @@ EIGEN_DEVICE_FUNC typename internal::traits<Derived>::Scalar DenseBase<Derived>::minCoeff(IndexType* rowId, IndexType* colId) const { + eigen_assert(this->rows()>0 && this->cols()>0 && "you are using an empty matrix"); + internal::min_coeff_visitor<Derived> minVisitor; this->visit(minVisitor); *rowId = minVisitor.row; @@ -214,6 +232,9 @@ DenseBase<Derived>::minCoeff(IndexType* rowId, IndexType* colId) const } /** \returns the minimum of all coefficients of *this and puts in *index its location. + * + * \warning the matrix must be not empty, otherwise an assertion is triggered. + * * \warning the result is undefined if \c *this contains NaN. * * \sa DenseBase::minCoeff(IndexType*,IndexType*), DenseBase::maxCoeff(IndexType*,IndexType*), DenseBase::visit(), DenseBase::minCoeff() @@ -224,6 +245,8 @@ EIGEN_DEVICE_FUNC typename internal::traits<Derived>::Scalar DenseBase<Derived>::minCoeff(IndexType* index) const { + eigen_assert(this->rows()>0 && this->cols()>0 && "you are using an empty matrix"); + EIGEN_STATIC_ASSERT_VECTOR_ONLY(Derived) internal::min_coeff_visitor<Derived> minVisitor; this->visit(minVisitor); @@ -233,6 +256,9 @@ DenseBase<Derived>::minCoeff(IndexType* index) const /** \fn DenseBase<Derived>::maxCoeff(IndexType* rowId, IndexType* colId) const * \returns the maximum of all coefficients of *this and puts in *row and *col its location. + * + * \warning the matrix must be not empty, otherwise an assertion is triggered. + * * \warning the result is undefined if \c *this contains NaN. * * \sa DenseBase::minCoeff(IndexType*,IndexType*), DenseBase::visit(), DenseBase::maxCoeff() @@ -243,6 +269,8 @@ EIGEN_DEVICE_FUNC typename internal::traits<Derived>::Scalar DenseBase<Derived>::maxCoeff(IndexType* rowPtr, IndexType* colPtr) const { + eigen_assert(this->rows()>0 && this->cols()>0 && "you are using an empty matrix"); + internal::max_coeff_visitor<Derived> maxVisitor; this->visit(maxVisitor); *rowPtr = maxVisitor.row; @@ -251,6 +279,9 @@ DenseBase<Derived>::maxCoeff(IndexType* rowPtr, IndexType* colPtr) const } /** \returns the maximum of all coefficients of *this and puts in *index its location. + * + * \warning the matrix must be not empty, otherwise an assertion is triggered. + * * \warning the result is undefined if \c *this contains NaN. * * \sa DenseBase::maxCoeff(IndexType*,IndexType*), DenseBase::minCoeff(IndexType*,IndexType*), DenseBase::visitor(), DenseBase::maxCoeff() @@ -261,6 +292,8 @@ EIGEN_DEVICE_FUNC typename internal::traits<Derived>::Scalar DenseBase<Derived>::maxCoeff(IndexType* index) const { + eigen_assert(this->rows()>0 && this->cols()>0 && "you are using an empty matrix"); + EIGEN_STATIC_ASSERT_VECTOR_ONLY(Derived) internal::max_coeff_visitor<Derived> maxVisitor; this->visit(maxVisitor); |