这里列举三种方式求矩阵的特征值与特征向量

#include <stdio.h>
#include <stdlib.h>
#include<Eigen/Eigen>using namespace std;
using namespace Eigen;void main()
{MatrixXd m(3, 3);m << 1,-2,2,-2,-2,4,2,4,-2;cout << m << endl << endl;EigenSolver<MatrixXd> es(m);cout << "第一种：" << endl;cout << "特征值为："  << endl;cout << es.eigenvalues() << endl;cout << "特征向量为：" <<endl;cout << es.eigenvectors() << endl << endl;cout << "第二种：" << endl;Matrix3d D = es.pseudoEigenvalueMatrix();Matrix3d V = es.pseudoEigenvectors();cout << D << endl << endl;cout << V << endl << endl;cout << "第三种：" << endl;MatrixXd value= es.eigenvalues().real();MatrixXd vector= es.eigenvectors().real();cout << value<< endl << endl;cout << vector<< endl << endl;}

运行结果