cart-elc

Source code for CART-ELC
git clone git://git.laack.co/cart-elc.git
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matrix_function.cpp (7447B)


      1 // This file is part of Eigen, a lightweight C++ template library
      2 // for linear algebra.
      3 //
      4 // Copyright (C) 2010 Jitse Niesen <jitse@maths.leeds.ac.uk>
      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 #include "main.h"
     11 #include <unsupported/Eigen/MatrixFunctions>
     12 
     13 // Variant of VERIFY_IS_APPROX which uses absolute error instead of
     14 // relative error.
     15 #define VERIFY_IS_APPROX_ABS(a, b) VERIFY(test_isApprox_abs(a, b))
     16 
     17 template<typename Type1, typename Type2>
     18 inline bool test_isApprox_abs(const Type1& a, const Type2& b)
     19 {
     20   return ((a-b).array().abs() < test_precision<typename Type1::RealScalar>()).all();
     21 }
     22 
     23 
     24 // Returns a matrix with eigenvalues clustered around 0, 1 and 2.
     25 template<typename MatrixType>
     26 MatrixType randomMatrixWithRealEivals(const Index size)
     27 {
     28   typedef typename MatrixType::Scalar Scalar;
     29   typedef typename MatrixType::RealScalar RealScalar;
     30   MatrixType diag = MatrixType::Zero(size, size);
     31   for (Index i = 0; i < size; ++i) {
     32     diag(i, i) = Scalar(RealScalar(internal::random<int>(0,2)))
     33       + internal::random<Scalar>() * Scalar(RealScalar(0.01));
     34   }
     35   MatrixType A = MatrixType::Random(size, size);
     36   HouseholderQR<MatrixType> QRofA(A);
     37   return QRofA.householderQ().inverse() * diag * QRofA.householderQ();
     38 }
     39 
     40 template <typename MatrixType, int IsComplex = NumTraits<typename internal::traits<MatrixType>::Scalar>::IsComplex>
     41 struct randomMatrixWithImagEivals
     42 {
     43   // Returns a matrix with eigenvalues clustered around 0 and +/- i.
     44   static MatrixType run(const Index size);
     45 };
     46 
     47 // Partial specialization for real matrices
     48 template<typename MatrixType>
     49 struct randomMatrixWithImagEivals<MatrixType, 0>
     50 {
     51   static MatrixType run(const Index size)
     52   {
     53     typedef typename MatrixType::Scalar Scalar;
     54     MatrixType diag = MatrixType::Zero(size, size);
     55     Index i = 0;
     56     while (i < size) {
     57       Index randomInt = internal::random<Index>(-1, 1);
     58       if (randomInt == 0 || i == size-1) {
     59         diag(i, i) = internal::random<Scalar>() * Scalar(0.01);
     60         ++i;
     61       } else {
     62         Scalar alpha = Scalar(randomInt) + internal::random<Scalar>() * Scalar(0.01);
     63         diag(i, i+1) = alpha;
     64         diag(i+1, i) = -alpha;
     65         i += 2;
     66       }
     67     }
     68     MatrixType A = MatrixType::Random(size, size);
     69     HouseholderQR<MatrixType> QRofA(A);
     70     return QRofA.householderQ().inverse() * diag * QRofA.householderQ();
     71   }
     72 };
     73 
     74 // Partial specialization for complex matrices
     75 template<typename MatrixType>
     76 struct randomMatrixWithImagEivals<MatrixType, 1>
     77 {
     78   static MatrixType run(const Index size)
     79   {
     80     typedef typename MatrixType::Scalar Scalar;
     81     typedef typename MatrixType::RealScalar RealScalar;
     82     const Scalar imagUnit(0, 1);
     83     MatrixType diag = MatrixType::Zero(size, size);
     84     for (Index i = 0; i < size; ++i) {
     85       diag(i, i) = Scalar(RealScalar(internal::random<Index>(-1, 1))) * imagUnit
     86         + internal::random<Scalar>() * Scalar(RealScalar(0.01));
     87     }
     88     MatrixType A = MatrixType::Random(size, size);
     89     HouseholderQR<MatrixType> QRofA(A);
     90     return QRofA.householderQ().inverse() * diag * QRofA.householderQ();
     91   }
     92 };
     93 
     94 
     95 template<typename MatrixType>
     96 void testMatrixExponential(const MatrixType& A)
     97 {
     98   typedef typename internal::traits<MatrixType>::Scalar Scalar;
     99   typedef typename NumTraits<Scalar>::Real RealScalar;
    100   typedef std::complex<RealScalar> ComplexScalar;
    101 
    102   VERIFY_IS_APPROX(A.exp(), A.matrixFunction(internal::stem_function_exp<ComplexScalar>));
    103 }
    104 
    105 template<typename MatrixType>
    106 void testMatrixLogarithm(const MatrixType& A)
    107 {
    108   typedef typename internal::traits<MatrixType>::Scalar Scalar;
    109   typedef typename NumTraits<Scalar>::Real RealScalar;
    110 
    111   MatrixType scaledA;
    112   RealScalar maxImagPartOfSpectrum = A.eigenvalues().imag().cwiseAbs().maxCoeff();
    113   if (maxImagPartOfSpectrum >= RealScalar(0.9L * EIGEN_PI))
    114     scaledA = A * RealScalar(0.9L * EIGEN_PI) / maxImagPartOfSpectrum;
    115   else
    116     scaledA = A;
    117 
    118   // identity X.exp().log() = X only holds if Im(lambda) < pi for all eigenvalues of X
    119   MatrixType expA = scaledA.exp();
    120   MatrixType logExpA = expA.log();
    121   VERIFY_IS_APPROX(logExpA, scaledA);
    122 }
    123 
    124 template<typename MatrixType>
    125 void testHyperbolicFunctions(const MatrixType& A)
    126 {
    127   // Need to use absolute error because of possible cancellation when
    128   // adding/subtracting expA and expmA.
    129   VERIFY_IS_APPROX_ABS(A.sinh(), (A.exp() - (-A).exp()) / 2);
    130   VERIFY_IS_APPROX_ABS(A.cosh(), (A.exp() + (-A).exp()) / 2);
    131 }
    132 
    133 template<typename MatrixType>
    134 void testGonioFunctions(const MatrixType& A)
    135 {
    136   typedef typename MatrixType::Scalar Scalar;
    137   typedef typename NumTraits<Scalar>::Real RealScalar;
    138   typedef std::complex<RealScalar> ComplexScalar;
    139   typedef Matrix<ComplexScalar, MatrixType::RowsAtCompileTime, 
    140                  MatrixType::ColsAtCompileTime, MatrixType::Options> ComplexMatrix;
    141 
    142   ComplexScalar imagUnit(0,1);
    143   ComplexScalar two(2,0);
    144 
    145   ComplexMatrix Ac = A.template cast<ComplexScalar>();
    146   
    147   ComplexMatrix exp_iA = (imagUnit * Ac).exp();
    148   ComplexMatrix exp_miA = (-imagUnit * Ac).exp();
    149   
    150   ComplexMatrix sinAc = A.sin().template cast<ComplexScalar>();
    151   VERIFY_IS_APPROX_ABS(sinAc, (exp_iA - exp_miA) / (two*imagUnit));
    152   
    153   ComplexMatrix cosAc = A.cos().template cast<ComplexScalar>();
    154   VERIFY_IS_APPROX_ABS(cosAc, (exp_iA + exp_miA) / 2);
    155 }
    156 
    157 template<typename MatrixType>
    158 void testMatrix(const MatrixType& A)
    159 {
    160   testMatrixExponential(A);
    161   testMatrixLogarithm(A);
    162   testHyperbolicFunctions(A);
    163   testGonioFunctions(A);
    164 }
    165 
    166 template<typename MatrixType>
    167 void testMatrixType(const MatrixType& m)
    168 {
    169   // Matrices with clustered eigenvalue lead to different code paths
    170   // in MatrixFunction.h and are thus useful for testing.
    171 
    172   const Index size = m.rows();
    173   for (int i = 0; i < g_repeat; i++) {
    174     testMatrix(MatrixType::Random(size, size).eval());
    175     testMatrix(randomMatrixWithRealEivals<MatrixType>(size));
    176     testMatrix(randomMatrixWithImagEivals<MatrixType>::run(size));
    177   }
    178 }
    179 
    180 template<typename MatrixType>
    181 void testMapRef(const MatrixType& A)
    182 {
    183   // Test if passing Ref and Map objects is possible
    184   // (Regression test for Bug #1796)
    185   Index size = A.rows();
    186   MatrixType X; X.setRandom(size, size);
    187   MatrixType Y(size,size);
    188   Ref<      MatrixType> R(Y);
    189   Ref<const MatrixType> Rc(X);
    190   Map<      MatrixType> M(Y.data(), size, size);
    191   Map<const MatrixType> Mc(X.data(), size, size);
    192 
    193   X = X*X; // make sure sqrt is possible
    194   Y = X.sqrt();
    195   R = Rc.sqrt();
    196   M = Mc.sqrt();
    197   Y = X.exp();
    198   R = Rc.exp();
    199   M = Mc.exp();
    200   X = Y; // make sure log is possible
    201   Y = X.log();
    202   R = Rc.log();
    203   M = Mc.log();
    204 
    205   Y = X.cos() + Rc.cos() + Mc.cos();
    206   Y = X.sin() + Rc.sin() + Mc.sin();
    207 
    208   Y = X.cosh() + Rc.cosh() + Mc.cosh();
    209   Y = X.sinh() + Rc.sinh() + Mc.sinh();
    210 }
    211 
    212 
    213 EIGEN_DECLARE_TEST(matrix_function)
    214 {
    215   CALL_SUBTEST_1(testMatrixType(Matrix<float,1,1>()));
    216   CALL_SUBTEST_2(testMatrixType(Matrix3cf()));
    217   CALL_SUBTEST_3(testMatrixType(MatrixXf(8,8)));
    218   CALL_SUBTEST_4(testMatrixType(Matrix2d()));
    219   CALL_SUBTEST_5(testMatrixType(Matrix<double,5,5,RowMajor>()));
    220   CALL_SUBTEST_6(testMatrixType(Matrix4cd()));
    221   CALL_SUBTEST_7(testMatrixType(MatrixXd(13,13)));
    222 
    223   CALL_SUBTEST_1(testMapRef(Matrix<float,1,1>()));
    224   CALL_SUBTEST_2(testMapRef(Matrix3cf()));
    225   CALL_SUBTEST_3(testMapRef(MatrixXf(8,8)));
    226   CALL_SUBTEST_7(testMapRef(MatrixXd(13,13)));
    227 }