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 
inverse_permutation_4x4()14 template<typename MatrixType> void inverse_permutation_4x4()
15 {
16   typedef typename MatrixType::Scalar Scalar;
17   Vector4i indices(0,1,2,3);
18   for(int i = 0; i < 24; ++i)
19   {
20     MatrixType m = PermutationMatrix<4>(indices);
21     MatrixType inv = m.inverse();
22     double error = double( (m*inv-MatrixType::Identity()).norm() / NumTraits<Scalar>::epsilon() );
23     EIGEN_DEBUG_VAR(error)
24     VERIFY(error == 0.0);
25     std::next_permutation(indices.data(),indices.data()+4);
26   }
27 }
28 
inverse_general_4x4(int repeat)29 template<typename MatrixType> void inverse_general_4x4(int repeat)
30 {
31   using std::abs;
32   typedef typename MatrixType::Scalar Scalar;
33   typedef typename MatrixType::RealScalar RealScalar;
34   double error_sum = 0., error_max = 0.;
35   for(int i = 0; i < repeat; ++i)
36   {
37     MatrixType m;
38     RealScalar absdet;
39     do {
40       m = MatrixType::Random();
41       absdet = abs(m.determinant());
42     } while(absdet < NumTraits<Scalar>::epsilon());
43     MatrixType inv = m.inverse();
44     double error = double( (m*inv-MatrixType::Identity()).norm() * absdet / NumTraits<Scalar>::epsilon() );
45     error_sum += error;
46     error_max = (std::max)(error_max, error);
47   }
48   std::cerr << "inverse_general_4x4, Scalar = " << type_name<Scalar>() << std::endl;
49   double error_avg = error_sum / repeat;
50   EIGEN_DEBUG_VAR(error_avg);
51   EIGEN_DEBUG_VAR(error_max);
52    // FIXME that 1.25 used to be a 1.0 until the NumTraits changes on 28 April 2010, what's going wrong??
53    // FIXME that 1.25 used to be 1.2 until we tested gcc 4.1 on 30 June 2010 and got 1.21.
54   VERIFY(error_avg < (NumTraits<Scalar>::IsComplex ? 8.0 : 1.25));
55   VERIFY(error_max < (NumTraits<Scalar>::IsComplex ? 64.0 : 20.0));
56 
57   {
58     int s = 5;//internal::random<int>(4,10);
59     int i = 0;//internal::random<int>(0,s-4);
60     int j = 0;//internal::random<int>(0,s-4);
61     Matrix<Scalar,5,5> mat(s,s);
62     mat.setRandom();
63     MatrixType submat = mat.template block<4,4>(i,j);
64     MatrixType mat_inv = mat.template block<4,4>(i,j).inverse();
65     VERIFY_IS_APPROX(mat_inv, submat.inverse());
66     mat.template block<4,4>(i,j) = submat.inverse();
67     VERIFY_IS_APPROX(mat_inv, (mat.template block<4,4>(i,j)));
68   }
69 }
70 
test_prec_inverse_4x4()71 void test_prec_inverse_4x4()
72 {
73   CALL_SUBTEST_1((inverse_permutation_4x4<Matrix4f>()));
74   CALL_SUBTEST_1(( inverse_general_4x4<Matrix4f>(200000 * g_repeat) ));
75   CALL_SUBTEST_1(( inverse_general_4x4<Matrix<float,4,4,RowMajor> >(200000 * g_repeat) ));
76 
77   CALL_SUBTEST_2((inverse_permutation_4x4<Matrix<double,4,4,RowMajor> >()));
78   CALL_SUBTEST_2(( inverse_general_4x4<Matrix<double,4,4,ColMajor> >(200000 * g_repeat) ));
79   CALL_SUBTEST_2(( inverse_general_4x4<Matrix<double,4,4,RowMajor> >(200000 * g_repeat) ));
80 
81   CALL_SUBTEST_3((inverse_permutation_4x4<Matrix4cf>()));
82   CALL_SUBTEST_3((inverse_general_4x4<Matrix4cf>(50000 * g_repeat)));
83 }
84