determinant.cpp (2275B)
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 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 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 }