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884a718b0a
gives up enforcing constness. I really tried to enforce it, but it really was much hassle because our expression templates can be lvalues (not only rvalues) and so much code had to be written twice.
83 lines
2.9 KiB
C++
83 lines
2.9 KiB
C++
// This file is part of Eigen, a lightweight C++ template library
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// for linear algebra. Eigen itself is part of the KDE project.
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//
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// Copyright (C) 2006-2007 Benoit Jacob <jacob@math.jussieu.fr>
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//
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// Eigen is free software; you can redistribute it and/or modify it under the
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// terms of the GNU General Public License as published by the Free Software
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// Foundation; either version 2 or (at your option) any later version.
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//
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// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY
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// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
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// FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
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// details.
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//
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// You should have received a copy of the GNU General Public License along
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// with Eigen; if not, write to the Free Software Foundation, Inc., 51
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// Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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//
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// As a special exception, if other files instantiate templates or use macros
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// or functions from this file, or you compile this file and link it
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// with other works to produce a work based on this file, this file does not
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// by itself cause the resulting work to be covered by the GNU General Public
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// License. This exception does not invalidate any other reasons why a work
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// based on this file might be covered by the GNU General Public License.
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#ifndef EI_DIFFERENCE_H
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#define EI_DIFFERENCE_H
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template<typename Lhs, typename Rhs> class Difference
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: public Object<typename Lhs::Scalar, Difference<Lhs, Rhs> >
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{
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public:
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typedef typename Lhs::Scalar Scalar;
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typedef typename Lhs::Ref LhsRef;
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typedef typename Rhs::Ref RhsRef;
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friend class Object<Scalar, Difference>;
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static const int RowsAtCompileTime = Lhs::RowsAtCompileTime,
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ColsAtCompileTime = Rhs::ColsAtCompileTime;
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Difference(const LhsRef& lhs, const RhsRef& rhs)
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: m_lhs(lhs), m_rhs(rhs)
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{
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assert(lhs.rows() == rhs.rows() && lhs.cols() == rhs.cols());
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}
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Difference(const Difference& other)
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: m_lhs(other.m_lhs), m_rhs(other.m_rhs) {}
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EI_INHERIT_ASSIGNMENT_OPERATORS(Difference)
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private:
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const Difference& _ref() const { return *this; }
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int _rows() const { return m_lhs.rows(); }
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int _cols() const { return m_lhs.cols(); }
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Scalar _read(int row, int col) const
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{
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return m_lhs.read(row, col) - m_rhs.read(row, col);
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}
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protected:
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const LhsRef m_lhs;
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const RhsRef m_rhs;
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};
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template<typename Scalar, typename Derived1, typename Derived2>
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Difference<Derived1, Derived2>
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operator-(const Object<Scalar, Derived1> &mat1, const Object<Scalar, Derived2> &mat2)
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{
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return Difference<Derived1, Derived2>(mat1.ref(), mat2.ref());
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}
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template<typename Scalar, typename Derived>
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template<typename OtherDerived>
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Derived &
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Object<Scalar, Derived>::operator-=(const Object<Scalar, OtherDerived> &other)
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{
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return *this = *this - other;
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}
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#endif // EI_DIFFERENCE_H
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