test/submatrices.cpp

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra. Eigen itself is part of the KDE project.
//
// Copyright (C) 2006-2008 Benoit Jacob <jacob@math.jussieu.fr>
//
// Eigen is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either 
// version 3 of the License, or (at your option) any later version.
//
// Alternatively, you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2 of 
// the License, or (at your option) any later version.
//
// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public 
// License and a copy of the GNU General Public License along with
// Eigen. If not, see <http://www.gnu.org/licenses/>.

#include "main.h"

namespace Eigen {

// check minor separately in order to avoid the possible creation of a zero-sized
// array. Comes from a compilation error with gcc-3.4 or gcc-4 with -ansi -pedantic.
// Another solution would be to declare the array like this: T m_data[Size==0?1:Size]; in MatrixStorage
// but this is probably not bad to raise such an error at compile time...
template<typename Scalar, int _Rows, int _Cols> struct CheckMinor
{
    typedef Matrix<Scalar, _Rows, _Cols> MatrixType;
    CheckMinor(MatrixType& m1, int r1, int c1)
    {
        int rows = m1.rows();
        int cols = m1.cols();

        Matrix<Scalar, Dynamic, Dynamic> mi = m1.minor(0,0).eval();
        VERIFY_IS_APPROX(mi, m1.block(1,1,rows-1,cols-1));
        mi = m1.minor(r1,c1);
        VERIFY_IS_APPROX(mi.transpose(), m1.transpose().minor(c1,r1));
        //check operator(), both constant and non-constant, on minor()
        m1.minor(r1,c1)(0,0) = m1.minor(0,0)(0,0);
    }
};

template<typename Scalar> struct CheckMinor<Scalar,1,1>
{
    typedef Matrix<Scalar, 1, 1> MatrixType;
    CheckMinor(MatrixType&, int, int) {}
};

template<typename MatrixType> void submatrices(const MatrixType& m)
{
  /* this test covers the following files:
     Row.h Column.h Block.h Minor.h DiagonalCoeffs.h
  */
  typedef typename MatrixType::Scalar Scalar;
  typedef Matrix<Scalar, MatrixType::Traits::RowsAtCompileTime, 1> VectorType;
  typedef Matrix<Scalar, 1, MatrixType::Traits::ColsAtCompileTime> RowVectorType;
  int rows = m.rows();
  int cols = m.cols();
  
  MatrixType m1 = MatrixType::random(rows, cols),
             m2 = MatrixType::random(rows, cols),
             m3(rows, cols),
             mzero = MatrixType::zero(rows, cols),
             identity = Matrix<Scalar, MatrixType::Traits::RowsAtCompileTime, MatrixType::Traits::RowsAtCompileTime>
                              ::identity(rows, rows),
             square = Matrix<Scalar, MatrixType::Traits::RowsAtCompileTime, MatrixType::Traits::RowsAtCompileTime>
                              ::random(rows, rows);
  VectorType v1 = VectorType::random(rows),
             v2 = VectorType::random(rows),
             v3 = VectorType::random(rows),
             vzero = VectorType::zero(rows);

  Scalar s1 = ei_random<Scalar>();
  
  int r1 = ei_random<int>(0,rows-1);
  int r2 = ei_random<int>(r1,rows-1);
  int c1 = ei_random<int>(0,cols-1);
  int c2 = ei_random<int>(c1,cols-1);
  
  //check row() and col()
  VERIFY_IS_APPROX(m1.col(c1).transpose(), m1.transpose().row(c1));
  VERIFY_IS_APPROX(square.row(r1).dot(m1.col(c1)), square.lazyProduct(m1.conjugate())(r1,c1));
  //check operator(), both constant and non-constant, on row() and col()
  m1.row(r1) += s1 * m1.row(r2);
  m1.col(c1) += s1 * m1.col(c2);
  
  //check block()
  Matrix<Scalar,Dynamic,Dynamic> b1(1,1); b1(0,0) = m1(r1,c1);
  RowVectorType br1(m1.block(r1,0,1,cols));
  VectorType bc1(m1.block(0,c1,rows,1));
  VERIFY_IS_APPROX(b1, m1.block(r1,c1,1,1));
  VERIFY_IS_APPROX(m1.row(r1), br1);
  VERIFY_IS_APPROX(m1.col(c1), bc1);
  //check operator(), both constant and non-constant, on block()
  m1.block(r1,c1,r2-r1+1,c2-c1+1) = s1 * m2.block(0, 0, r2-r1+1,c2-c1+1);
  m1.block(r1,c1,r2-r1+1,c2-c1+1)(r2-r1,c2-c1) = m2.block(0, 0, r2-r1+1,c2-c1+1)(0,0);
  
  //check minor()
  CheckMinor<Scalar, MatrixType::Traits::RowsAtCompileTime, MatrixType::Traits::ColsAtCompileTime> checkminor(m1,r1,c1);
  
  //check diagonal()
  VERIFY_IS_APPROX(m1.diagonal(), m1.transpose().diagonal());
  m2.diagonal() = 2 * m1.diagonal();
  m2.diagonal()[0] *= 3;
  VERIFY_IS_APPROX(m2.diagonal()[0], static_cast<Scalar>(6) * m1.diagonal()[0]);
}

void EigenTest::testSubmatrices()
{
  for(int i = 0; i < m_repeat; i++) {
    submatrices(Matrix<float, 1, 1>());
    submatrices(Matrix4d());
    submatrices(MatrixXcf(3, 3));
    submatrices(MatrixXi(8, 12));
    submatrices(MatrixXcd(20, 20));
    
    // test fixed block() separately as it is a template method so doesn't support
    // being called as a member of a class that is itself a template parameter
    // (at least as of g++ 4.2)
    Matrix<float, 6, 8> m = Matrix<float, 6, 8>::random();
    float s = ei_random<float>();
    // test fixed block() as lvalue
    m.block<2,5>(1,1) *= s;
    // test operator() on fixed block() both as constant and non-constant
    m.block<2,5>(1,1)(0, 3) = m.block<2,5>(1,1)(1,2);
    // check that fixed block() and block() agree
    MatrixXf b = m.block<3,2>(3,3);
    VERIFY_IS_APPROX(b, m.block(3,3,3,2));
  }
}

} // namespace Eigen