1// This file is part of Eigen, a lightweight C++ template library
2// for linear algebra.
3//
4// Copyright (C) 2009 Benoit Jacob <jacob.benoit.1@gmail.com>
5//
6// This Source Code Form is subject to the terms of the Mozilla
7// Public License v. 2.0. If a copy of the MPL was not distributed
8// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
9
10#ifndef EIGEN_MISC_IMAGE_H
11#define EIGEN_MISC_IMAGE_H
12
13namespace Eigen {
14
15namespace internal {
16
17/** \class image_retval_base
18 *
19 */
20template<typename DecompositionType>
21struct traits<image_retval_base<DecompositionType> >
22{
23 typedef typename DecompositionType::MatrixType MatrixType;
24 typedef Matrix<
25 typename MatrixType::Scalar,
26 MatrixType::RowsAtCompileTime, // the image is a subspace of the destination space, whose
27 // dimension is the number of rows of the original matrix
28 Dynamic, // we don't know at compile time the dimension of the image (the rank)
29 MatrixType::Options,
30 MatrixType::MaxRowsAtCompileTime, // the image matrix will consist of columns from the original matrix,
31 MatrixType::MaxColsAtCompileTime // so it has the same number of rows and at most as many columns.
32 > ReturnType;
33};
34
35template<typename _DecompositionType> struct image_retval_base
36 : public ReturnByValue<image_retval_base<_DecompositionType> >
37{
38 typedef _DecompositionType DecompositionType;
39 typedef typename DecompositionType::MatrixType MatrixType;
40 typedef ReturnByValue<image_retval_base> Base;
41
42 image_retval_base(const DecompositionType& dec, const MatrixType& originalMatrix)
43 : m_dec(dec), m_rank(dec.rank()),
44 m_cols(m_rank == 0 ? 1 : m_rank),
45 m_originalMatrix(originalMatrix)
46 {}
47
48 inline Index rows() const { return m_dec.rows(); }
49 inline Index cols() const { return m_cols; }
50 inline Index rank() const { return m_rank; }
51 inline const DecompositionType& dec() const { return m_dec; }
52 inline const MatrixType& originalMatrix() const { return m_originalMatrix; }
53
54 template<typename Dest> inline void evalTo(Dest& dst) const
55 {
56 static_cast<const image_retval<DecompositionType>*>(this)->evalTo(dst);
57 }
58
59 protected:
60 const DecompositionType& m_dec;
61 Index m_rank, m_cols;
62 const MatrixType& m_originalMatrix;
63};
64
65} // end namespace internal
66
67#define EIGEN_MAKE_IMAGE_HELPERS(DecompositionType) \
68 typedef typename DecompositionType::MatrixType MatrixType; \
69 typedef typename MatrixType::Scalar Scalar; \
70 typedef typename MatrixType::RealScalar RealScalar; \
71 typedef Eigen::internal::image_retval_base<DecompositionType> Base; \
72 using Base::dec; \
73 using Base::originalMatrix; \
74 using Base::rank; \
75 using Base::rows; \
76 using Base::cols; \
77 image_retval(const DecompositionType& dec, const MatrixType& originalMatrix) \
78 : Base(dec, originalMatrix) {}
79
80} // end namespace Eigen
81
82#endif // EIGEN_MISC_IMAGE_H
83