//C++ #include "engine.h" //使用Matlab引擎需要包含的頭文件#include <iostream>using namespace std;int main(){ Engine *m_engine; //創建Matlab引擎 m_engine = NULL; //初始化引擎  if((!m_engine && !(m_engine = engOpen(NULL)))) //打開引擎，此時會打開一個Matlab命令行窗口 {  return -1; } engSetVisible(m_engine,1); //將命令行窗口設為可見  char buffer[255]; //記錄調試信息，方便調試 engOutputBuffer(m_engine, buffer, 255);    double A[3][3] = {-1,1,0,   -4,3,0,    1,0,2};  mxArray* AObj = mxCreateDoubleMatrix(3, 3, mxREAL); //創建Matlab的矩陣（大小3*3，實數）  memcpy(mxGetPr(AObj), A, 3*sizeof(double)); //將C++的數據傳入Matlab中  engPutVariable(m_engine, "A", AObj); //將AObj的值賦給A   engEvalString(m_engine, "cd('E://MatlabScripts')"); //進入Matlab代碼的路徑    //調用Matlab中定義的函數“computeEigens”，文件名需與函數名一致，即“computeEigens.m”  int k = 2; engEvalString(m_engine, "[eigVector,eigValue] = computeEigens(A, k);");    //存儲計算結果 engEvalString(m_engine,"save('E://eigVec_eigV.mat','eigVector','eigValue');");  printf("%s", buffer);  mxDestroyArray(AObj); //銷毀Matlab數組  if (m_engine) //關閉Matlab引擎 { engClose(m_engine); m_engine = NULL; }  return 0; }

%調用的Matlab代碼%E:/MatlabScripts/computeEigens.m function [ eigVector, eigValue ] = computeEigens( M, n_Eigens ) %n_Eigens為要求的特征值數量 [EigenVectors,EigenValues] = eig(M); [sortedEigenValues, index] = sort(diag(EigenValues)); eigValue = sortedEigenValues(1:n_Eigens); idx = index(1:n_Eigens); eigVector = EigenVectors(:,idx); end