123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127 |
- // This file is part of Eigen, a lightweight C++ template library
- // for linear algebra.
- //
- // Copyright (C) 2008-2014 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_COREITERATORS_H
- #define EIGEN_COREITERATORS_H
- namespace Eigen {
- /* This file contains the respective InnerIterator definition of the expressions defined in Eigen/Core
- */
- namespace internal {
- template<typename XprType, typename EvaluatorKind>
- class inner_iterator_selector;
- }
- /** \class InnerIterator
- * \brief An InnerIterator allows to loop over the element of any matrix expression.
- *
- * \warning To be used with care because an evaluator is constructed every time an InnerIterator iterator is constructed.
- *
- * TODO: add a usage example
- */
- template<typename XprType>
- class InnerIterator
- {
- protected:
- typedef internal::inner_iterator_selector<XprType, typename internal::evaluator_traits<XprType>::Kind> IteratorType;
- typedef internal::evaluator<XprType> EvaluatorType;
- typedef typename internal::traits<XprType>::Scalar Scalar;
- public:
- /** Construct an iterator over the \a outerId -th row or column of \a xpr */
- InnerIterator(const XprType &xpr, const Index &outerId)
- : m_eval(xpr), m_iter(m_eval, outerId, xpr.innerSize())
- {}
-
- /// \returns the value of the current coefficient.
- EIGEN_STRONG_INLINE Scalar value() const { return m_iter.value(); }
- /** Increment the iterator \c *this to the next non-zero coefficient.
- * Explicit zeros are not skipped over. To skip explicit zeros, see class SparseView
- */
- EIGEN_STRONG_INLINE InnerIterator& operator++() { m_iter.operator++(); return *this; }
- /// \returns the column or row index of the current coefficient.
- EIGEN_STRONG_INLINE Index index() const { return m_iter.index(); }
- /// \returns the row index of the current coefficient.
- EIGEN_STRONG_INLINE Index row() const { return m_iter.row(); }
- /// \returns the column index of the current coefficient.
- EIGEN_STRONG_INLINE Index col() const { return m_iter.col(); }
- /// \returns \c true if the iterator \c *this still references a valid coefficient.
- EIGEN_STRONG_INLINE operator bool() const { return m_iter; }
-
- protected:
- EvaluatorType m_eval;
- IteratorType m_iter;
- private:
- // If you get here, then you're not using the right InnerIterator type, e.g.:
- // SparseMatrix<double,RowMajor> A;
- // SparseMatrix<double>::InnerIterator it(A,0);
- template<typename T> InnerIterator(const EigenBase<T>&,Index outer);
- };
- namespace internal {
- // Generic inner iterator implementation for dense objects
- template<typename XprType>
- class inner_iterator_selector<XprType, IndexBased>
- {
- protected:
- typedef evaluator<XprType> EvaluatorType;
- typedef typename traits<XprType>::Scalar Scalar;
- enum { IsRowMajor = (XprType::Flags&RowMajorBit)==RowMajorBit };
-
- public:
- EIGEN_STRONG_INLINE inner_iterator_selector(const EvaluatorType &eval, const Index &outerId, const Index &innerSize)
- : m_eval(eval), m_inner(0), m_outer(outerId), m_end(innerSize)
- {}
- EIGEN_STRONG_INLINE Scalar value() const
- {
- return (IsRowMajor) ? m_eval.coeff(m_outer, m_inner)
- : m_eval.coeff(m_inner, m_outer);
- }
- EIGEN_STRONG_INLINE inner_iterator_selector& operator++() { m_inner++; return *this; }
- EIGEN_STRONG_INLINE Index index() const { return m_inner; }
- inline Index row() const { return IsRowMajor ? m_outer : index(); }
- inline Index col() const { return IsRowMajor ? index() : m_outer; }
- EIGEN_STRONG_INLINE operator bool() const { return m_inner < m_end && m_inner>=0; }
- protected:
- const EvaluatorType& m_eval;
- Index m_inner;
- const Index m_outer;
- const Index m_end;
- };
- // For iterator-based evaluator, inner-iterator is already implemented as
- // evaluator<>::InnerIterator
- template<typename XprType>
- class inner_iterator_selector<XprType, IteratorBased>
- : public evaluator<XprType>::InnerIterator
- {
- protected:
- typedef typename evaluator<XprType>::InnerIterator Base;
- typedef evaluator<XprType> EvaluatorType;
-
- public:
- EIGEN_STRONG_INLINE inner_iterator_selector(const EvaluatorType &eval, const Index &outerId, const Index &/*innerSize*/)
- : Base(eval, outerId)
- {}
- };
- } // end namespace internal
- } // end namespace Eigen
- #endif // EIGEN_COREITERATORS_H
|