1 // This file is part of Eigen, a lightweight C++ template library
2 // for linear algebra.
3 //
4 // Copyright (C) 2008 Benoit Jacob <[email protected]>
5 // Copyright (C) 2008 Gael Guennebaud <[email protected]>
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 Index size = m.rows();
20
21 MatrixType m1(size, size), m2(size, size);
22 m1.setRandom();
23 m2.setRandom();
24 typedef typename MatrixType::Scalar Scalar;
25 Scalar x = internal::random<Scalar>();
26 VERIFY_IS_APPROX(MatrixType::Identity(size, size).determinant(), Scalar(1));
27 VERIFY_IS_APPROX((m1*m2).eval().determinant(), m1.determinant() * m2.determinant());
28 if(size==1) return;
29 Index i = internal::random<Index>(0, size-1);
30 Index j;
31 do {
32 j = internal::random<Index>(0, size-1);
33 } while(j==i);
34 m2 = m1;
35 m2.row(i).swap(m2.row(j));
36 VERIFY_IS_APPROX(m2.determinant(), -m1.determinant());
37 m2 = m1;
38 m2.col(i).swap(m2.col(j));
39 VERIFY_IS_APPROX(m2.determinant(), -m1.determinant());
40 VERIFY_IS_APPROX(m2.determinant(), m2.transpose().determinant());
41 VERIFY_IS_APPROX(numext::conj(m2.determinant()), m2.adjoint().determinant());
42 m2 = m1;
43 m2.row(i) += x*m2.row(j);
44 VERIFY_IS_APPROX(m2.determinant(), m1.determinant());
45 m2 = m1;
46 m2.row(i) *= x;
47 VERIFY_IS_APPROX(m2.determinant(), m1.determinant() * x);
48
49 // check empty matrix
50 VERIFY_IS_APPROX(m2.block(0,0,0,0).determinant(), Scalar(1));
51 }
52
EIGEN_DECLARE_TEST(determinant)53 EIGEN_DECLARE_TEST(determinant)
54 {
55 for(int i = 0; i < g_repeat; i++) {
56 int s = 0;
57 CALL_SUBTEST_1( determinant(Matrix<float, 1, 1>()) );
58 CALL_SUBTEST_2( determinant(Matrix<double, 2, 2>()) );
59 CALL_SUBTEST_3( determinant(Matrix<double, 3, 3>()) );
60 CALL_SUBTEST_4( determinant(Matrix<double, 4, 4>()) );
61 CALL_SUBTEST_5( determinant(Matrix<std::complex<double>, 10, 10>()) );
62 s = internal::random<int>(1,EIGEN_TEST_MAX_SIZE/4);
63 CALL_SUBTEST_6( determinant(MatrixXd(s, s)) );
64 TEST_SET_BUT_UNUSED_VARIABLE(s)
65 }
66 }
67