C++ VectorType::array方法代码示例

void verify_is_approx_upto_permutation(const VectorType& vec1, const VectorType& vec2)
{
  typedef typename NumTraits<typename VectorType::Scalar>::Real RealScalar;

  VERIFY(vec1.cols() == 1);
  VERIFY(vec2.cols() == 1);
  VERIFY(vec1.rows() == vec2.rows());
  for (int k = 1; k <= vec1.rows(); ++k)
  {
    VERIFY_IS_APPROX(vec1.array().pow(RealScalar(k)).sum(), vec2.array().pow(RealScalar(k)).sum());
  }
}

template<typename VectorType> void lpNorm(const VectorType& v)
{
  VectorType u = VectorType::Random(v.size());

  VERIFY_IS_APPROX(u.template lpNorm<Infinity>(), u.cwiseAbs().maxCoeff());
  VERIFY_IS_APPROX(u.template lpNorm<1>(), u.cwiseAbs().sum());
  VERIFY_IS_APPROX(u.template lpNorm<2>(), internal::sqrt(u.array().abs().square().sum()));
  VERIFY_IS_APPROX(internal::pow(u.template lpNorm<5>(), typename VectorType::RealScalar(5)), u.array().abs().pow(5).sum());
}

typename GaussianProcess<TScalarType>::MatrixType GaussianProcess<TScalarType>::InvertKernelMatrix(const typename GaussianProcess<TScalarType>::MatrixType &K,
                                                      typename GaussianProcess<TScalarType>::InversionMethod inv_method = GaussianProcess<TScalarType>::FullPivotLU,
                                                                                                   bool stable) const{
    // compute core matrix
    if(debug){
        std::cout << "GaussianProcess::InvertKernelMatrix: inverting kernel matrix... ";
        std::cout.flush();
    }

    typename GaussianProcess<TScalarType>::MatrixType core;

    switch(inv_method){
    // standard method: fast but not that accurate
    // Uses the LU decomposition with full pivoting for the inversion
    case FullPivotLU:{
        if(debug) std::cout << " (inversion method: FullPivotLU) " << std::flush;
        try{
            if(stable){
                core = K.inverse();
            }
            else{
                if(debug) std::cout << " (using lapack) " << std::flush;
                core = lapack::lu_invert<TScalarType>(K);
            }
        }
        catch(lapack::LAPACKException& e){
            core = K.inverse();
        }
    }
    break;

    // very accurate and very slow method, use it for small problems
    // Uses the two-sided Jacobi SVD decomposition
    case JacobiSVD:{
        if(debug) std::cout << " (inversion method: JacobiSVD) " << std::flush;
        Eigen::JacobiSVD<MatrixType> jacobisvd(K, Eigen::ComputeThinU | Eigen::ComputeThinV);
        if((jacobisvd.singularValues().real().array() < 0).any() && debug){
            std::cout << "GaussianProcess::InvertKernelMatrix: warning: there are negative eigenvalues.";
            std::cout.flush();
        }
        core = jacobisvd.matrixV() * VectorType(1/jacobisvd.singularValues().array()).asDiagonal() * jacobisvd.matrixU().transpose();
    }
    break;

    // accurate method and faster than Jacobi SVD.
    // Uses the bidiagonal divide and conquer SVD
    case BDCSVD:{
        if(debug) std::cout << " (inversion method: BDCSVD) " << std::flush;
#ifdef EIGEN_BDCSVD_H
        Eigen::BDCSVD<MatrixType> bdcsvd(K, Eigen::ComputeThinU | Eigen::ComputeThinV);
        if((bdcsvd.singularValues().real().array() < 0).any() && debug){
            std::cout << "GaussianProcess::InvertKernelMatrix: warning: there are negative eigenvalues.";
            std::cout.flush();
        }
        core = bdcsvd.matrixV() * VectorType(1/bdcsvd.singularValues().array()).asDiagonal() * bdcsvd.matrixU().transpose();
#else
        // this is checked, since BDCSVD is currently not in the newest release
        throw std::string("GaussianProcess::InvertKernelMatrix: BDCSVD is not supported by the provided Eigen library.");
#endif

    }
    break;

    // faster than the SVD method but less stable
    // computes the eigenvalues/eigenvectors of selfadjoint matrices
    case SelfAdjointEigenSolver:{
        if(debug) std::cout << " (inversion method: SelfAdjointEigenSolver) " << std::flush;
        try{
            core = lapack::chol_invert<TScalarType>(K);
        }
        catch(lapack::LAPACKException& e){
            Eigen::SelfAdjointEigenSolver<MatrixType> es;
            es.compute(K);
            VectorType eigenValues = es.eigenvalues().reverse();
            MatrixType eigenVectors = es.eigenvectors().rowwise().reverse();
            if((eigenValues.real().array() < 0).any() && debug){
                std::cout << "GaussianProcess::InvertKernelMatrix: warning: there are negative eigenvalues.";
                std::cout.flush();
            }
            core = eigenVectors * VectorType(1/eigenValues.array()).asDiagonal() * eigenVectors.transpose();
        }
    }
    break;
    }

    if(debug) std::cout << "[done]" << std::endl;
    return core;
}

 static ScalarType asum(std::size_t /*N*/, VectorType const & x)
 { return x.array().abs().sum(); }

void ContinuousAction::Unnormalize( const VectorType& scales,
                                    const VectorType& offsets )
{
	output = ( output.array() * scales.array() ).matrix() + offsets;
}

void ContinuousAction::Normalize( const VectorType& scales,
                                  const VectorType& offsets )
{
	output = ( ( output - offsets ).array() / scales.array() ).matrix();
}