1 // This file is part of Eigen, a lightweight C++ template library
2 // for linear algebra.
3 //
4 // Copyright (C) 2008 Benoit Jacob <jacob.benoit.1@gmail.com>
5 // Copyright (C) 2008 Gael Guennebaud <gael.guennebaud@inria.fr>
6 //
7 // This Source Code Form is subject to the terms of the Mozilla
8 // Public License v. 2.0. If a copy of the MPL was not distributed
9 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
10
11 #include "main.h"
12 #include <Eigen/LU>
13
determinant(const MatrixType & m)14 template<typename MatrixType> void determinant(const MatrixType& m)
15 {
16 /* this test covers the following files:
17 Determinant.h
18 */
19 typedef typename MatrixType::Index Index;
20 Index size = m.rows();
21
22 MatrixType m1(size, size), m2(size, size);
23 m1.setRandom();
24 m2.setRandom();
25 typedef typename MatrixType::Scalar Scalar;
26 Scalar x = internal::random<Scalar>();
27 VERIFY_IS_APPROX(MatrixType::Identity(size, size).determinant(), Scalar(1));
28 VERIFY_IS_APPROX((m1*m2).eval().determinant(), m1.determinant() * m2.determinant());
29 if(size==1) return;
30 Index i = internal::random<Index>(0, size-1);
31 Index j;
32 do {
33 j = internal::random<Index>(0, size-1);
34 } while(j==i);
35 m2 = m1;
36 m2.row(i).swap(m2.row(j));
37 VERIFY_IS_APPROX(m2.determinant(), -m1.determinant());
38 m2 = m1;
39 m2.col(i).swap(m2.col(j));
40 VERIFY_IS_APPROX(m2.determinant(), -m1.determinant());
41 VERIFY_IS_APPROX(m2.determinant(), m2.transpose().determinant());
42 VERIFY_IS_APPROX(numext::conj(m2.determinant()), m2.adjoint().determinant());
43 m2 = m1;
44 m2.row(i) += x*m2.row(j);
45 VERIFY_IS_APPROX(m2.determinant(), m1.determinant());
46 m2 = m1;
47 m2.row(i) *= x;
48 VERIFY_IS_APPROX(m2.determinant(), m1.determinant() * x);
49
50 // check empty matrix
51 VERIFY_IS_APPROX(m2.block(0,0,0,0).determinant(), Scalar(1));
52 }
53
test_determinant()54 void test_determinant()
55 {
56 for(int i = 0; i < g_repeat; i++) {
57 int s = 0;
58 CALL_SUBTEST_1( determinant(Matrix<float, 1, 1>()) );
59 CALL_SUBTEST_2( determinant(Matrix<double, 2, 2>()) );
60 CALL_SUBTEST_3( determinant(Matrix<double, 3, 3>()) );
61 CALL_SUBTEST_4( determinant(Matrix<double, 4, 4>()) );
62 CALL_SUBTEST_5( determinant(Matrix<std::complex<double>, 10, 10>()) );
63 s = internal::random<int>(1,EIGEN_TEST_MAX_SIZE/4);
64 CALL_SUBTEST_6( determinant(MatrixXd(s, s)) );
65 TEST_SET_BUT_UNUSED_VARIABLE(s)
66 }
67 }
68