Function comparisons

external/eigen/test/array_for_matrix.cpp:89–153

}

template<typename MatrixType> void comparisons(const MatrixType& m)
{
  using std::abs;
  typedef typename MatrixType::Scalar Scalar;
  typedef typename NumTraits<Scalar>::Real RealScalar;

  Index rows = m.rows();
  Index cols = m.cols();

  Index r = internal::random<Index>(0, rows-1),
        c = internal::random<Index>(0, cols-1);

  MatrixType m1 = MatrixType::Random(rows, cols),
             m2 = MatrixType::Random(rows, cols),
             m3(rows, cols);

  VERIFY(((m1.array() + Scalar(1)) > m1.array()).all());
  VERIFY(((m1.array() - Scalar(1)) < m1.array()).all());
  if (rows*cols>1)
  {
    m3 = m1;
    m3(r,c) += 1;
    VERIFY(! (m1.array() < m3.array()).all() );
    VERIFY(! (m1.array() > m3.array()).all() );
  }

  // comparisons to scalar
  VERIFY( (m1.array() != (m1(r,c)+1) ).any() );
  VERIFY( (m1.array() > (m1(r,c)-1) ).any() );
  VERIFY( (m1.array() < (m1(r,c)+1) ).any() );
  VERIFY( (m1.array() == m1(r,c) ).any() );
  VERIFY( m1.cwiseEqual(m1(r,c)).any() );

  // test Select
  VERIFY_IS_APPROX( (m1.array()<m2.array()).select(m1,m2), m1.cwiseMin(m2) );
  VERIFY_IS_APPROX( (m1.array()>m2.array()).select(m1,m2), m1.cwiseMax(m2) );
  Scalar mid = (m1.cwiseAbs().minCoeff() + m1.cwiseAbs().maxCoeff())/Scalar(2);
  for (int j=0; j<cols; ++j)
  for (int i=0; i<rows; ++i)
    m3(i,j) = abs(m1(i,j))<mid ? 0 : m1(i,j);
  VERIFY_IS_APPROX( (m1.array().abs()<MatrixType::Constant(rows,cols,mid).array())
                        .select(MatrixType::Zero(rows,cols),m1), m3);
  // shorter versions:
  VERIFY_IS_APPROX( (m1.array().abs()<MatrixType::Constant(rows,cols,mid).array())
                        .select(0,m1), m3);
  VERIFY_IS_APPROX( (m1.array().abs()>=MatrixType::Constant(rows,cols,mid).array())
                        .select(m1,0), m3);
  // even shorter version:
  VERIFY_IS_APPROX( (m1.array().abs()<mid).select(0,m1), m3);

  // count
  VERIFY(((m1.array().abs()+1)>RealScalar(0.1)).count() == rows*cols);

  // and/or
  VERIFY( ((m1.array()<RealScalar(0)).matrix() && (m1.array()>RealScalar(0)).matrix()).count() == 0);
  VERIFY( ((m1.array()<RealScalar(0)).matrix() || (m1.array()>=RealScalar(0)).matrix()).count() == rows*cols);
  RealScalar a = m1.cwiseAbs().mean();
  VERIFY( ((m1.array()<-a).matrix() || (m1.array()>a).matrix()).count() == (m1.cwiseAbs().array()>a).count());