1 // This file is part of Eigen, a lightweight C++ template library
2 // for linear algebra.
3 //
4 // Copyright (C) 2009 Benoit Jacob <jacob.benoit.1@gmail.com>
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 <Eigen/LU>
12 #include <algorithm>
13 
type_name()14 template<typename T> std::string type_name() { return "other"; }
type_name()15 template<> std::string type_name<float>() { return "float"; }
type_name()16 template<> std::string type_name<double>() { return "double"; }
type_name()17 template<> std::string type_name<int>() { return "int"; }
type_name()18 template<> std::string type_name<std::complex<float> >() { return "complex<float>"; }
type_name()19 template<> std::string type_name<std::complex<double> >() { return "complex<double>"; }
type_name()20 template<> std::string type_name<std::complex<int> >() { return "complex<int>"; }
21 
22 #define EIGEN_DEBUG_VAR(x) std::cerr << #x << " = " << x << std::endl;
23 
epsilon()24 template<typename T> inline typename NumTraits<T>::Real epsilon()
25 {
26  return std::numeric_limits<typename NumTraits<T>::Real>::epsilon();
27 }
28 
inverse_permutation_4x4()29 template<typename MatrixType> void inverse_permutation_4x4()
30 {
31   typedef typename MatrixType::Scalar Scalar;
32   typedef typename MatrixType::RealScalar RealScalar;
33   Vector4i indices(0,1,2,3);
34   for(int i = 0; i < 24; ++i)
35   {
36     MatrixType m = MatrixType::Zero();
37     m(indices(0),0) = 1;
38     m(indices(1),1) = 1;
39     m(indices(2),2) = 1;
40     m(indices(3),3) = 1;
41     MatrixType inv = m.inverse();
42     double error = double( (m*inv-MatrixType::Identity()).norm() / epsilon<Scalar>() );
43     VERIFY(error == 0.0);
44     std::next_permutation(indices.data(),indices.data()+4);
45   }
46 }
47 
inverse_general_4x4(int repeat)48 template<typename MatrixType> void inverse_general_4x4(int repeat)
49 {
50   typedef typename MatrixType::Scalar Scalar;
51   typedef typename MatrixType::RealScalar RealScalar;
52   double error_sum = 0., error_max = 0.;
53   for(int i = 0; i < repeat; ++i)
54   {
55     MatrixType m;
56     RealScalar absdet;
57     do {
58       m = MatrixType::Random();
59       absdet = ei_abs(m.determinant());
60     } while(absdet < 10 * epsilon<Scalar>());
61     MatrixType inv = m.inverse();
62     double error = double( (m*inv-MatrixType::Identity()).norm() * absdet / epsilon<Scalar>() );
63     error_sum += error;
64     error_max = std::max(error_max, error);
65   }
66   std::cerr << "inverse_general_4x4, Scalar = " << type_name<Scalar>() << std::endl;
67   double error_avg = error_sum / repeat;
68   EIGEN_DEBUG_VAR(error_avg);
69   EIGEN_DEBUG_VAR(error_max);
70   VERIFY(error_avg < (NumTraits<Scalar>::IsComplex ? 8.0 : 1.25));
71   VERIFY(error_max < (NumTraits<Scalar>::IsComplex ? 64.0 : 20.0));
72 }
73 
test_eigen2_prec_inverse_4x4()74 void test_eigen2_prec_inverse_4x4()
75 {
76   CALL_SUBTEST_1((inverse_permutation_4x4<Matrix4f>()));
77   CALL_SUBTEST_1(( inverse_general_4x4<Matrix4f>(200000 * g_repeat) ));
78 
79   CALL_SUBTEST_2((inverse_permutation_4x4<Matrix<double,4,4,RowMajor> >()));
80   CALL_SUBTEST_2(( inverse_general_4x4<Matrix<double,4,4,RowMajor> >(200000 * g_repeat) ));
81 
82   CALL_SUBTEST_3((inverse_permutation_4x4<Matrix4cf>()));
83   CALL_SUBTEST_3((inverse_general_4x4<Matrix4cf>(50000 * g_repeat)));
84 }
85