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Diffstat (limited to 'eigen/Eigen/src/Core/Inverse.h')
-rw-r--r-- | eigen/Eigen/src/Core/Inverse.h | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/eigen/Eigen/src/Core/Inverse.h b/eigen/Eigen/src/Core/Inverse.h new file mode 100644 index 0000000..b76f043 --- /dev/null +++ b/eigen/Eigen/src/Core/Inverse.h @@ -0,0 +1,118 @@ +// This file is part of Eigen, a lightweight C++ template library +// for linear algebra. +// +// Copyright (C) 2014 Gael Guennebaud <gael.guennebaud@inria.fr> +// +// This Source Code Form is subject to the terms of the Mozilla +// Public License v. 2.0. If a copy of the MPL was not distributed +// with this file, You can obtain one at http://mozilla.org/MPL/2.0/. + +#ifndef EIGEN_INVERSE_H +#define EIGEN_INVERSE_H + +namespace Eigen { + +template<typename XprType,typename StorageKind> class InverseImpl; + +namespace internal { + +template<typename XprType> +struct traits<Inverse<XprType> > + : traits<typename XprType::PlainObject> +{ + typedef typename XprType::PlainObject PlainObject; + typedef traits<PlainObject> BaseTraits; + enum { + Flags = BaseTraits::Flags & RowMajorBit + }; +}; + +} // end namespace internal + +/** \class Inverse + * + * \brief Expression of the inverse of another expression + * + * \tparam XprType the type of the expression we are taking the inverse + * + * This class represents an abstract expression of A.inverse() + * and most of the time this is the only way it is used. + * + */ +template<typename XprType> +class Inverse : public InverseImpl<XprType,typename internal::traits<XprType>::StorageKind> +{ +public: + typedef typename XprType::StorageIndex StorageIndex; + typedef typename XprType::PlainObject PlainObject; + typedef typename XprType::Scalar Scalar; + typedef typename internal::ref_selector<XprType>::type XprTypeNested; + typedef typename internal::remove_all<XprTypeNested>::type XprTypeNestedCleaned; + typedef typename internal::ref_selector<Inverse>::type Nested; + typedef typename internal::remove_all<XprType>::type NestedExpression; + + explicit EIGEN_DEVICE_FUNC Inverse(const XprType &xpr) + : m_xpr(xpr) + {} + + EIGEN_DEVICE_FUNC Index rows() const { return m_xpr.rows(); } + EIGEN_DEVICE_FUNC Index cols() const { return m_xpr.cols(); } + + EIGEN_DEVICE_FUNC const XprTypeNestedCleaned& nestedExpression() const { return m_xpr; } + +protected: + XprTypeNested m_xpr; +}; + +// Generic API dispatcher +template<typename XprType, typename StorageKind> +class InverseImpl + : public internal::generic_xpr_base<Inverse<XprType> >::type +{ +public: + typedef typename internal::generic_xpr_base<Inverse<XprType> >::type Base; + typedef typename XprType::Scalar Scalar; +private: + + Scalar coeff(Index row, Index col) const; + Scalar coeff(Index i) const; +}; + +namespace internal { + +/** \internal + * \brief Default evaluator for Inverse expression. + * + * This default evaluator for Inverse expression simply evaluate the inverse into a temporary + * by a call to internal::call_assignment_no_alias. + * Therefore, inverse implementers only have to specialize Assignment<Dst,Inverse<...>, ...> for + * there own nested expression. + * + * \sa class Inverse + */ +template<typename ArgType> +struct unary_evaluator<Inverse<ArgType> > + : public evaluator<typename Inverse<ArgType>::PlainObject> +{ + typedef Inverse<ArgType> InverseType; + typedef typename InverseType::PlainObject PlainObject; + typedef evaluator<PlainObject> Base; + + enum { Flags = Base::Flags | EvalBeforeNestingBit }; + + unary_evaluator(const InverseType& inv_xpr) + : m_result(inv_xpr.rows(), inv_xpr.cols()) + { + ::new (static_cast<Base*>(this)) Base(m_result); + internal::call_assignment_no_alias(m_result, inv_xpr); + } + +protected: + PlainObject m_result; +}; + +} // end namespace internal + +} // end namespace Eigen + +#endif // EIGEN_INVERSE_H |